CN113518814A

CN113518814A - Solid wafer and method for producing semiconductor chip with film-like adhesive

Info

Publication number: CN113518814A
Application number: CN202080018319.0A
Authority: CN
Inventors: 岩屋涉; 佐藤阳辅
Original assignee: Lintec Corp
Current assignee: Lintec Corp
Priority date: 2019-03-07
Filing date: 2020-03-06
Publication date: 2021-10-19
Anticipated expiration: 2040-03-06
Also published as: KR20210134905A; WO2020179897A1; JP2022125110A; KR102672948B1; TWI825282B; CN113518814B; JP7141515B2; TW202044424A; JPWO2020179897A1; JP7141566B2

Abstract

The present invention provides a die bond sheet (101) comprising a base material (11) and formed by laminating an adhesive layer (12), an intermediate layer (13) and a film-like adhesive (14) on the base material (11) in this order, wherein in the die bond sheet (101), [ tensile elastic modulus of the intermediate layer (13) at 0 ℃ ]/[ tensile elastic modulus of the base material (11) at 0 ℃ ] has a value of 0.5 or less.

Description

Solid wafer and method for manufacturing semiconductor chip with film-like adhesive

Technical Field

The present invention relates to a fixed wafer and a method for manufacturing a semiconductor chip with a film adhesive. The present application claims priority based on japanese patent application No. 2019-041886 filed in japan on 3, 7, 2019, and the contents thereof are incorporated herein.

Background

In the manufacture of a semiconductor device, a semiconductor chip with a film-like adhesive, which includes a semiconductor chip and a film-like adhesive provided on the back surface thereof, is used. Here, the back surface of the semiconductor chip is a surface opposite to a surface of the semiconductor chip on which a circuit is formed (in this specification, it may be abbreviated as "circuit-formed surface").

The semiconductor chip with the film-like adhesive can be manufactured by the following method, for example.

That is, first, a back-grinding tape (also called a surface protection tape) is attached to a surface of a semiconductor wafer on which a circuit is formed (in this specification, it may be abbreviated as "circuit-formed surface").

Then, the laser beam is irradiated so as to be focused on a focal point set in the semiconductor wafer, thereby forming a modified layer in the semiconductor wafer. Next, a surface of the semiconductor wafer opposite to the circuit forming surface (in this specification, it may be abbreviated as "back surface") is polished by a polishing machine, whereby the thickness of the semiconductor wafer is adjusted to a target value, and the semiconductor wafer is divided at a portion where the modified layer is formed by a force applied to the semiconductor wafer at the time of polishing, thereby forming a plurality of semiconductor chips. Such a method of dividing a semiconductor wafer accompanied by formation of a modified layer is called a Stealth Dicing (registered trademark), and is fundamentally completely different from laser Dicing in which a semiconductor wafer is cut from its surface while the semiconductor wafer is irradiated with a laser beam to trim an irradiated portion.

Next, 1 wafer was attached to the back surface (in other words, the polished surface) of the semiconductor chips fixed to the back-polishing tape, which was polished as described above. Here, as the die, for example, a die having a substrate and a pressure-sensitive adhesive layer and a film-like pressure-sensitive adhesive layer sequentially laminated on the substrate is exemplified. At this time, the film-like adhesive in the fixing wafer is heated to an appropriate temperature and is attached to the back surface of the semiconductor chip in a softened state. Thus, the die bond sheet can be stably attached to the semiconductor chip.

Next, after the back grinding tape is removed from the semiconductor chip, the fixed wafer is cooled and stretched in a direction parallel to the surface (for example, the surface of the film-like adhesive to which the semiconductor chip is attached) of the fixed wafer, thereby cutting (dividing) the film-like adhesive along the outer periphery of the semiconductor chip.

As described above, a semiconductor chip with a film-like adhesive, which includes a semiconductor chip and a cut film-like adhesive provided on the back surface thereof, can be obtained.

After the semiconductor chip with the film-like adhesive is obtained, the laminated sheet of the base material and the adhesive layer is stretched (spread) in a direction parallel to the surface thereof in a state where the semiconductor chip with the film-like adhesive is placed thereon. Further, the peripheral edge portion of the semiconductor chip on which the adhesive tape is not mounted in the laminate sheet is heated so as to maintain this state. In summary, the peripheral edge portion is shrunk, and thereafter, a distance (sometimes referred to as "notch width" in this specification) between adjacent semiconductor chips is appropriately maintained on the laminated sheet.

Next, the semiconductor chip with the film-like adhesive is separated from the laminated sheet and picked up. In this case, when the adhesive layer is curable, the adhesive property is reduced by curing the adhesive layer, and thus pickup is facilitated.

As a result, a semiconductor chip with a film-like adhesive used for manufacturing a semiconductor device can be stably obtained.

The picked-up semiconductor chip is die-bonded to the circuit formation surface of the substrate with a film-like adhesive provided on the back surface thereof, 1 or more other semiconductor chips are further stacked on the semiconductor chip as necessary, wire bonding is performed, and then the whole is sealed with a resin. With the semiconductor package obtained in this way, a target semiconductor device can be finally manufactured.

As a die bonding sheet having a film-like adhesive which can be cut by spreading, there is disclosed a dicing die bonding tape (corresponding to the die bonding sheet) which is configured by sequentially laminating a base material having a specific range of tensile properties, an adhesive layer, a base material layer (corresponding to an intermediate layer), and an adhesive layer (corresponding to the film-like adhesive) (see patent document 1). Since the solid-crystal sheet includes the base layer corresponding to the intermediate layer, it is considered that cutting with high precision can be performed when the film-like adhesive is spread.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5946650

Disclosure of Invention

Technical problem to be solved by the invention

As described above, when the wafer is expanded while being cooled, the region between the semiconductor chips, that is, the notch width is required to be sufficiently wide with respect to the elongation of the base material, and the film-like adhesive is required to be stably cut (divided) along the outer peripheries of the semiconductor chips.

On the other hand, it is not clear whether the solid-crystal wafer disclosed in patent document 1 has such characteristics sufficiently.

The present invention provides a die bonding sheet which is configured by including a base material, an adhesive agent layer, and a film-like adhesive agent, and which has a sufficiently wide slit width with respect to the elongation of the base material when expanded while cooled, and which can stably cut (divide) the film-like adhesive agent along the outer periphery of a semiconductor chip.

Means for solving the problems

The present invention provides a die bonding sheet comprising a substrate, and an adhesive layer, an intermediate layer, and a film-like adhesive laminated in this order on the substrate, wherein the value of [ the tensile elastic modulus Ei 'of the intermediate layer at 0 ℃ ]/[ the tensile elastic modulus Eb' of the substrate at 0 ℃ ] is 0.5 or less.

In the solid wafer of the present invention, the maximum value of the width of the intermediate layer may be 150 to 160mm, 200 to 210mm, or 300 to 310 mm.

The present invention provides a method for manufacturing a semiconductor chip with a film-shaped adhesive, the semiconductor chip with the film-shaped adhesive is provided with a semiconductor chip and a film-shaped adhesive arranged on the back surface of the semiconductor chip, the method comprises the following steps: a step of irradiating a laser beam so as to focus on a focal point set inside a semiconductor wafer, thereby forming a modified layer inside the semiconductor wafer; a step of obtaining a semiconductor chip group in which a plurality of semiconductor chips are aligned by grinding the back surface of the semiconductor wafer on which the modified layer is formed and dividing the semiconductor wafer at a portion where the modified layer is formed by a force applied to the semiconductor wafer during grinding; heating the fixed wafer while adhering the film-like adhesive to the back surfaces of all the semiconductor chips in the semiconductor chip group; a step of stretching the fixed wafer in a direction parallel to the surface thereof while cooling the fixed wafer bonded to the semiconductor chip group, thereby cutting the film-like adhesive along the outer periphery of the semiconductor chips to obtain a plurality of semiconductor chip groups with the film-like adhesive, the semiconductor chip groups being arranged in alignment with each other; a step of spreading a laminated sheet derived from the base material, the adhesive agent layer, and the intermediate layer of the solid wafer after obtaining the semiconductor chip with the film-like adhesive in a direction parallel to the surface of the adhesive agent layer, and further heating the peripheral edge portion of the semiconductor chip without the film-like adhesive placed thereon in the laminated sheet so as to maintain the state; and a step of separating the semiconductor chip with the film-like adhesive from the intermediate layer in the laminated sheet after heating the peripheral edge portion, thereby picking up the semiconductor chip with the film-like adhesive, wherein a difference between a maximum value of the width of the intermediate layer and a maximum value of the width of the semiconductor wafer is 0to 10 mm.

Effects of the invention

According to the present invention, there can be provided a die bond sheet comprising a base material, an adhesive agent layer, and a film-like adhesive agent, wherein when the die bond sheet is expanded while being cooled, the width of a cut is sufficiently wide with respect to the elongation of the base material, and the film-like adhesive agent can be stably cut (divided) along the outer periphery of a semiconductor chip.

Drawings

Fig. 1 is a cross-sectional view schematically showing a solid wafer according to an embodiment of the present invention.

Fig. 2 is a top view of the solid wafer shown in fig. 1.

Fig. 3A is a sectional view schematically illustrating a method for manufacturing a semiconductor chip to be used as a solid wafer according to an embodiment of the present invention.

Fig. 3B is a sectional view schematically illustrating a method for manufacturing a semiconductor chip to be used as a solid wafer according to an embodiment of the present invention.

Fig. 3C is a sectional view schematically illustrating a method for manufacturing a semiconductor chip to be used as a solid wafer according to an embodiment of the present invention.

Fig. 4A is a sectional view for schematically illustrating a method of using a solid wafer according to an embodiment of the present invention.

Fig. 4B is a sectional view for schematically illustrating a method of using a solid wafer according to an embodiment of the present invention.

Fig. 4C is a sectional view for schematically illustrating a method of using a solid wafer according to an embodiment of the present invention.

Fig. 5 is a plan view schematically showing an evaluation object for explaining a measurement position of a notch width in evaluating notch retentivity in the example.

Detailed Description

Gu wafer

The die bond sheet according to one embodiment of the present invention comprises a substrate, and an adhesive layer, an intermediate layer, and a film-like adhesive are laminated on the substrate in this order, wherein the value of [ the tensile elastic modulus Ei 'of the intermediate layer at 0 ℃ ]/[ the tensile elastic modulus Eb' of the substrate at 0 ℃ ] is 0.5 or less.

By setting the value of [ the tensile elastic modulus Ei 'of the intermediate layer at 0 ℃ (0 ℃)/[ the tensile elastic modulus Eb' of the base material at 0 ℃) ] of the solid-state wafer of the present embodiment to the upper limit value or less, the slit width can be made sufficiently wide with respect to the elongation of the base material, and therefore, when the solid-state wafer is expanded, the film-like adhesive can be stably cut (divided) along the outer periphery of the semiconductor chip.

In addition, unless otherwise specified, "laminate sheet" in the present specification means a laminate sheet having a structure in which the above-described base material, adhesive agent layer, and intermediate layer are laminated.

The solid-state chip of the present embodiment is preferably used as a semiconductor wafer after dicing. Here, as the semiconductor wafer after dicing, there are mentioned: a semiconductor wafer in which a plurality of semiconductor chips are arranged in order in advance; or a semiconductor wafer including a plurality of semiconductor chips arranged in this order and a region of the other semiconductor wafer not divided into semiconductor chips.

Such an object to be used as a solid chip can be obtained by dicing a semiconductor wafer as described below, for example.

That is, first, a back-grinding tape (surface protection tape) is attached to a surface of the semiconductor wafer on which the circuit is formed (i.e., a "circuit forming surface").

Then, the laser beam is irradiated so as to be focused on a focal point set in the semiconductor wafer, thereby forming a modified layer in the semiconductor wafer. The position of the focal point at this time is a position at which the semiconductor wafer is to be divided (diced), and the position is set so that a desired size, shape, and number of semiconductor chips can be obtained from the semiconductor wafer.

Next, a surface (i.e., a back surface) of the semiconductor wafer opposite to the circuit forming surface is polished by a polishing machine. Thus, the thickness of the semiconductor wafer is adjusted to a target value, and the semiconductor wafer is divided at the formation portion of the modified layer by a force applied to the semiconductor wafer at the time of polishing, thereby forming a plurality of semiconductor chips. Unlike other positions of the semiconductor wafer, the modified layer of the semiconductor wafer is modified by irradiation with laser light, and the intensity thereof is weakened. Therefore, by applying a force to the semiconductor wafer on which the modified layer is formed, a force is applied to the modified layer in the semiconductor wafer, and the semiconductor wafer is cracked at the modified layer, whereby a plurality of semiconductor chips can be obtained.

Depending on the conditions during polishing, a partial region of the semiconductor wafer may not be divided into semiconductor chips.

The solid wafer will be described in detail below with reference to the drawings. For the sake of easy understanding of the features of the present invention, important parts of the drawings used in the following description may be enlarged for convenience, and the dimensional ratios of the respective components are not necessarily the same as those in actual cases.

Fig. 1 is a sectional view schematically showing a solid wafer according to an embodiment of the present invention, and fig. 2 is a plan view of the solid wafer shown in fig. 1.

In the drawings subsequent to fig. 2, the same reference numerals as those in the already-described drawings are assigned to the same components as those shown in the already-described drawings, and detailed description thereof is omitted.

The die bond sheet 101 shown here includes a substrate 11, and is configured by laminating an adhesive layer 12, an intermediate layer 13, and a film-like adhesive 14 in this order on the substrate 11. The fixed wafer 101 further includes a release film 15 on the film-like adhesive 14.

In the die bond sheet 101, an adhesive layer 12 is provided on one surface (hereinafter, sometimes referred to as "first surface") 11a of a substrate 11, an intermediate layer 13 is provided on a surface (hereinafter, sometimes referred to as "first surface") 12a of the adhesive layer 12 opposite to the side on which the substrate 11 is provided, a film-like adhesive 14 is provided on a surface (hereinafter, sometimes referred to as "first surface") 13a of the intermediate layer 13 opposite to the side on which the adhesive layer 12 is provided, and a release film 15 is provided on a surface (hereinafter, sometimes referred to as "first surface") 14a of the film-like adhesive 14 opposite to the side on which the intermediate layer 13 is provided. As described above, the fixed wafer 101 is configured by sequentially laminating the base material 11, the adhesive layer 12, the intermediate layer 13, and the film-like adhesive 14 in the thickness direction thereof.

The fixed wafer 101 is used in the following manner: in a state where the release film 15 is removed, the first surface 14a of the film-like adhesive 14 is attached to a surface (i.e., a back surface) of the semiconductor chip or the semiconductor wafer (not shown) that is not completely divided, the surface being opposite to the circuit formation surface.

In the present specification, a laminate including a base material and an adhesive layer is sometimes referred to as a "support sheet". In fig. 1, reference numeral 1 denotes a support sheet.

When the intermediate layer 13 and the film-like adhesive 14 are viewed from above the intermediate layer 13 and the film-like adhesive 14 in a plan view, the planar shapes of the intermediate layer 13 and the film-like adhesive 14 are both circular, and the diameter of the intermediate layer 13 is the same as the diameter of the film-like adhesive 14.

In the die bond 101, the intermediate layer 13 and the film-like adhesive 14 are disposed so that their centers coincide with each other, in other words, so that the outer circumferential positions of the intermediate layer 13 and the film-like adhesive 14 coincide with each other in the radial direction.

The first surface 13a of the intermediate layer 13 and the first surface 14a of the film-like adhesive 14 are smaller in area than the first surface 12a of the adhesive layer 12. Further, the width W of the intermediate layer 13₁₃Maximum value (i.e., diameter) of (d) and width W of film-like adhesive 14₁₄Are smaller than the maximum value of the width of the adhesive layer 12 and the maximum value of the width of the base material 11. Therefore, in the die bond 101, a part of the first surface 12a of the adhesive layer 12 is not covered with the intermediate layer 13 and the film-like adhesive 14. The release film 15 is laminated on such a region of the first surface 12a of the adhesive agent layer 12 where the intermediate layer 13 and the film-like adhesive 14 are not laminated, in direct contact therewith, and this region is exposed in a state where the release film 15 is removed (hereinafter, this region may be referred to as a "non-laminated region" in the present specification).

In the die bond sheet 101 provided with the release film 15, the release film 15 may not be laminated in the region of the adhesive layer 12 not covered with the intermediate layer 13 and the film-like adhesive 14 as shown here.

The die 101 can be fixed by attaching a part of the non-lamination region of the adhesive layer 12 to a jig such as a ring frame for fixing a semiconductor wafer, in a state where the film-like adhesive 14 is not cut and is attached to the semiconductor chip or the like. Therefore, it is not necessary to separately provide a jig adhesive layer for fixing the wafer 101 to the jig on the wafer 101. Further, since it is not necessary to provide a jig adhesive layer, the fixed wafer 101 can be manufactured at low cost and efficiently.

As described above, the fixed wafer 101 has an advantageous effect by not having a jig adhesive layer, but may have a jig adhesive layer. In this case, the pressure-sensitive adhesive layer for a jig is provided in a region near the peripheral edge portion of the surface of any of the layers constituting the fixed wafer 101. Such a region includes a region not covered with the intermediate layer 13 and the film-like adhesive 14 on the first surface 12a of the adhesive layer 12.

The pressure-sensitive adhesive layer for a jig may be a known pressure-sensitive adhesive layer for a jig, and may have, for example, a single-layer structure containing a pressure-sensitive adhesive component, or a multilayer structure in which layers containing a pressure-sensitive adhesive component are laminated on both surfaces of a sheet as a core material.

Further, as described later, when so-called spreading is performed in which the solid wafer 101 is stretched in a direction parallel to the surface thereof (for example, the first surface 12a of the adhesive agent layer 12), the solid wafer 101 can be easily spread by the presence of the non-laminated region on the first surface 12a of the adhesive agent layer 12. Further, not only the film-shaped adhesive 14 can be easily cut, but also the peeling of the intermediate layer 13 and the film-shaped adhesive 14 from the adhesive layer 12 can be suppressed in some cases.

As described later, the fixed wafer 101 satisfies the condition that the value of [ the tensile elastic modulus Ei 'of the intermediate layer 13 at 0 ℃ ]/[ the tensile elastic modulus Eb' of the substrate 11 at 0 ℃ ] is 0.5 or less.

The solid-state wafer 101 preferably has the following characteristics when a test piece having a size of 4.5mm × 15mm prepared from the base material 11 is subjected to thermomechanical analysis (in the present specification, it may be referred to as "TMA").

That is, first, TMA was performed using a thermomechanical analyzer under a load of 2g so as not to cause a temperature change in the test piece, and the displacement X of the test piece at a temperature of 23 ℃ was measured₀。X₀Usually 0 (zero), or close to 0The numerical value of (c).

TMA was continued with the temperature rise rate set at 20 ℃/min and the load set at 2g, and the measurement X was measured₀The temperature of the test piece was raised to 70 ℃ and the maximum value X of the displacement of the test piece at that time was measured₁。X₁Usually the amount of displacement at a test piece temperature of 70 ℃. Further, X is usually satisfied₁≥X₀The conditions of (1).

Next, TMA was continued with the load set at 2g, and the measurement X was conducted at a temperature of 23 ℃₁The test piece was cooled and the minimum value X of the displacement of the test piece at that time was measured₂。X₂The displacement is generally the displacement at which the temperature of the test piece does not fluctuate (in other words, is the lowest) due to cooling.

X₀、X₁And X₂Since they are continuously measured by a series of TMAs, their measurement directions are all the same. Further, the load applied to the test piece was constant.

With respect to the fixed wafer 101, X acquired in this way is used₀And X₁And using formula (1): (X)₁-X₀) The rate of change of the amount of displacement of the test piece when heated is preferably 0to 2% as calculated by/15X 100.

Furthermore, using X derived in this manner₁And X₂And using formula (2): (X)₂-X₁) The rate of change in the amount of displacement of the test piece during cooling, calculated as/15X 100, is preferably-2 to 0%.

Furthermore, using X derived in this manner₂And X₀And using formula (3): (X)₂-X₀) The total change rate of the displacement amount of the test piece calculated by/15 × 100 is preferably-2 to 1%.

The solid crystal wafer according to the present embodiment is not limited to the solid crystal wafer shown in fig. 1 and 2, and the partial structure of the solid crystal wafer shown in fig. 1 and 2 may be changed, deleted, or added within a range not to impair the effect of the present invention.

For example, the die bond sheet of the present embodiment may include another layer not belonging to any one of the substrate, the adhesive layer, the intermediate layer, the film-like adhesive, the release film, and the adhesive layer for a jig. As shown in fig. 1, the die bond sheet of the present invention preferably includes an adhesive layer in direct contact with the substrate, an intermediate layer in direct contact with the adhesive layer, and a film-like adhesive in direct contact with the intermediate layer.

For example, in the solid-crystal wafer of the present embodiment, the planar shapes of the intermediate layer and the film-like adhesive may be shapes other than circular, and the planar shapes of the intermediate layer and the film-like adhesive may be the same or different from each other. Preferably, the area of the first surface of the intermediate layer and the area of the first surface of the film-like adhesive are both smaller than the area of the surface of the layer on the substrate side (for example, the first surface of the adhesive agent layer), and the area of the first surface of the intermediate layer and the area of the first surface of the film-like adhesive may be the same as or different from each other. The outer circumferential positions of the intermediate layer and the film-like adhesive may be uniform or nonuniform in the radial direction.

Next, the layers constituting the solid-state wafer of the present invention will be described in more detail.

O base material

The substrate is in the shape of a sheet or a film.

The material constituting the base material is preferably a variety of resins, and specific examples thereof include polyethylene (low density polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE), High Density Polyethylene (HDPE), etc.), polypropylene, polybutene, polybutadiene, polymethylpentene, styrene-ethylenebutylene-styrene block copolymer, polyvinyl chloride, vinyl chloride copolymer, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyurethane, urethane acrylate, Polyimide (PI), ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylate copolymer, ethylene copolymer other than ethylene- (meth) acrylic acid copolymer and ethylene- (meth) acrylate copolymer, polystyrene, polycarbonate, polyethylene terephthalate, and polyethylene terephthalate, and polyethylene terephthalate, and polyethylene terephthalate, and the like, Fluorine resins, hydrogenated products, modified products, crosslinked products, copolymers of any of the above resins, and the like.

In the present specification, "(meth) acrylic acid" is a concept including "acrylic acid" and "methacrylic acid". Similar terms to (meth) acrylic acid are also the same, for example, "(meth) acrylate" is a concept including "acrylate" and "methacrylate", and "(meth) acryl" is a concept including "acryl" and "methacryl".

The resin constituting the base material may be one kind only, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

The constituent material of the base material is preferably polyethylene, and more preferably Low Density Polyethylene (LDPE), in terms of easier adjustment of the rate of change during heating, the rate of change during cooling, and the overall rate of change.

The substrate may be composed of one layer (single layer) or a plurality of layers of two or more layers. When the substrate is composed of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is not particularly limited as long as the effect of the present invention is not impaired.

In the present specification, the phrase "a plurality of layers may be the same or different from each other" means "all the layers may be the same or different from each other, or only a part of the layers may be the same" and "a plurality of layers are different from each other" means "at least one of the constituent materials and the thicknesses of the respective layers are different from each other".

The thickness of the base material can be suitably selected according to the purpose, and is preferably 50 to 300. mu.m, and more preferably 60to 150. mu.m. By making the thickness of the base material more than the lower limit value, the structure of the base material is more stable. When the thickness of the base material is not more than the upper limit, the cuttability of the film-like adhesive is further improved when the die is expanded. Further, when the fixed wafer after cutting the film-like adhesive is spread (in other words, when the laminated sheet is spread), the effect of making the slit width sufficiently wide and maintaining the slit width with high uniformity is further increased.

Here, the "thickness of the substrate" refers to the thickness of the entire substrate, and for example, the thickness of the substrate composed of a plurality of layers refers to the total thickness of all the layers constituting the substrate.

In order to improve the adhesion between the substrate and another layer such as an adhesive layer provided thereon, the surface of the substrate may be subjected to an embossing treatment such as a sandblasting treatment, a solvent treatment, or an embossing treatment; corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone/ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, and other oxidation treatments.

In addition, the surface of the substrate may be subjected to primer treatment (primer treatment).

Further, the substrate may have: an antistatic coating; a layer for preventing the adhesion of the base material to other sheets or the adhesion of the base material to a suction table (suction table) when the wafers are stacked and fixed and stored.

The base material may contain various known additives such as a filler, a colorant, an antistatic agent, an antioxidant, an organic lubricant, a catalyst, and a softener (plasticizer) in addition to the main constituent material such as the resin.

A film or sheet having a resin as a constituent material has anisotropy depending on a production method thereof. For example, it is known that a film or sheet produced by molding a resin generally has properties that vary in the resin flow Direction (Machine Direction) and in the Direction orthogonal to the resin flow Direction (Transverse Direction) at the time of resin molding. In the present specification, the flow direction of the resin is sometimes referred to as "MD" and the direction perpendicular to the flow direction of the resin is sometimes referred to as "TD".

That is, when a film or sheet is processed, MD is a direction parallel to the flow direction of the film or sheet, and TD is a direction orthogonal to the flow direction of the film or sheet. When a film or sheet is stretched, MD is the stretching direction of the film or sheet, and TD is the direction orthogonal to the stretching direction of the film or sheet. The MD and TD of each layer can be distinguished from each other by optical analysis such as analysis of X-ray two-dimensional diffraction images, for example.

In this embodiment, a film or sheet produced by molding a resin, including a substrate, an intermediate layer, an adhesive layer, a film-like adhesive, and the like, may have MD and TD.

In the solid wafer, the MD of the base material (base material 11 in the case of the solid wafer 101 shown in fig. 1) is preferably matched with the MD of an intermediate layer (intermediate layer 13 in the case of the solid wafer 101 shown in fig. 1) described later. In other words, in the solid wafer, the TD of the base material is preferably coincident with the TD of the intermediate layer. The ease of expansion (expandability) of the solid wafer having the substrate and the intermediate layer disposed in this manner is more uniform in any direction. Further, by using such a die bond sheet, the cuttability by the spread film-like adhesive is further improved, and further, when the film-like adhesive is cut, a region between the semiconductor chips, so-called a notch, is further stably formed, and the uniformity of the width of the region (i.e., the notch width) is further improved. Further, by increasing the uniformity of the slit width in this manner, the effect of suppressing the occurrence of process defects when picking up a semiconductor chip with a film-like adhesive described later becomes remarkably high.

< rate of change of displacement of test piece made of base material upon heating >

The rate of change of the test piece produced from the substrate (substrate 11 in the case of the solid wafer 101 shown in FIG. 1) upon heating may be, for example, 0to 3%, as described above, preferably 0to 2%, for example, 0to 1.6%, 0to 1.2%, and 0to 0.9%, may be 0.2 to 2%, 0.4 to 2%, and 0.6 to 2%, and may be 0.2 to 1.6%, 0.4 to 1.2%, and 0.6 to 0.9%.

The rates of change in the test piece in the 2 or more measurement directions upon heating may be the same or different from each other. Here, "2 or more measurement directions of the rate of change upon heating" means 2 or more different directions among directions parallel to the first surface of the test piece (corresponding to the first surface of the base material). For example, when the test piece has MD and TD, the rate of change upon heating in MD of the test piece and the rate of change upon heating in TD of the test piece may be the same as or different from each other.

In the present embodiment, the rate of change in the test piece in any measurement direction upon heating may be, for example, 0to 3%, and preferably 0to 2%. For example, when the test piece has MD and TD, the rate of change upon heating may be, for example, 0to 3%, preferably 0to 2% in either or both of MD and TD, and may be any one of the 11 numerical ranges exemplified above in either or both of MD and TD. In this case, the combination of the numerical range of the MD change rate during heating and the numerical range of the TD change rate during heating is arbitrary.

< Rate of Change in Displacement of test piece made of base Material upon Cooling >

As described above, the test piece produced from the base material (base material 11 in the case of the fixed wafer 101 shown in FIG. 1) preferably has a change rate of-2 to 0% when it is left to cool, and may be any of-2 to-0.4%, 2 to-0.8%, 2 to-1.2%, and-2 to-1.6%, for example.

The test piece may have the same or different rates of change in the cooling time in 2 or more measurement directions. Here, "the measurement directions of 2 or more change rates in cooling" are the same as "the measurement directions of 2 or more change rates in heating" described above. For example, when the test piece has MD and TD, the cooling-time change rate of the MD of the test piece and the cooling-time change rate of the TD of the test piece may be the same as or different from each other.

In the present embodiment, it is preferable that the test piece has a rate of change in cooling in any measurement direction of-2 to 0%. For example, when the test piece has MD and TD, the rate of change in cooling is preferably-2 to 0% in both MD and TD, and may be any of the 4 numerical value ranges exemplified above in either or both MD and TD. In this case, the combination of the numerical range of the cooling time variation rate of MD and the numerical range of the cooling time variation rate of TD is arbitrary.

< comprehensive rate of change in amount of displacement of test piece made of base Material >

The total change rate of the test piece produced from the substrate (substrate 11 in the case of the fixed wafer 101 shown in FIG. 1) may be, for example, any one of-2 to 1.8%, and as described above, preferably-2 to 1%, for example-2 to 0.6%, -2 to 0.3%, -2 to 0%, -2 to 0.3%, and-2 to-0.6%, or any one of-1.8 to 1%, -1.6 to 1%, and-1.4 to 1%, or any one of-1.8 to 0.6%, -1.8 to 0.3%, -1.8 to 0%, 1.6 to-0.3%, and-1.4 to-0.6%.

Wherein the comprehensive change rate of the test piece is more preferably-2 to 0%.

The total change rates in 2 or more measurement directions of the test piece may be the same or different from each other. Here, the "2 or more measurement directions of the total change rate" is the same as the "2 or more measurement directions of the change rate during heating" described above. For example, when the test piece has MD and TD, the total change rate of MD of the test piece and the total change rate of TD of the test piece may be the same or different from each other.

In the present embodiment, the total change rate of the test piece in any measurement direction may be, for example, -2 to 1.8%, and preferably-2 to 1%. For example, when the test piece has MD and TD, the total change rate may be, for example, -2 to 1.8%, preferably-2 to 1% in either or both of MD and TD, and may be any one of the 15 numerical ranges exemplified above in either or both of MD and TD. In this case, the combination of the numerical range of the total change rate of MD and the numerical range of the total change rate of TD is arbitrary.

In the test piece made of a base material, it is preferable that: the heating-time change rate is any one of the 11 numerical ranges, the cooling-time change rate is any one of the 5 numerical ranges, and the total change rate is any one of the 15 numerical ranges.

Examples of such a test piece include a test piece having a rate of change in the heating in either or both of the MD and TD of 0.6 to 0.9%, a rate of change in the cooling in either or both of the MD and TD of-2 to-1.6%, and a total rate of change in either or both of the MD and TD of-1.4 to-0.6%. However, this is only one example of the test strip.

The thickness of the test piece to be measured for the rate of change during heating, the rate of change during cooling, and the overall rate of change is not particularly limited, and may be a thickness that allows the measurement to be performed with high accuracy. For example, the thickness of the test piece may be 10 to 200 μm.

The rate of change during heating, the rate of change during cooling, and the overall rate of change of the test piece made of the base material can be adjusted by adjusting the content of the base material, for example, the type and content of the resin.

< tensile elastic modulus Eb' of test piece made of substrate >

When a tensile test in which a test piece having a width of 15mm and a length of more than 100mm is produced from the base material (base material 11 in the case of the fixed wafer 101 shown in fig. 1) and is stretched at a stretching speed of 200mm/min is performed using tensillon with a collet pitch of 100mm and a temperature of 0 ℃, and a tensile elastic modulus Eb 'of the test piece at 0 ℃ in an elastic deformation region is measured, Eb' may be any one of, for example, 10 to 200MPa, 50 to 150MPa, and 70 to 120 MPa. By making Eb ' in the above range, the tensile elastic modulus becomes easier to adjust than Ei '/Eb '. Further, when Eb' is 50MPa or more, the die bond sheet can be more easily attached to the semiconductor wafer.

The cutting of the film-like adhesive by spreading the solid wafer is preferably performed at a temperature of 0 ℃ or around 0 ℃ from the viewpoint of improving the cutting property of the film-like adhesive. Therefore, in the above-mentioned fixed wafer, the tensile elastic modulus Eb' of the test piece made of the base material is defined as a value at 0 ℃. In the present embodiment, important physical properties highly correlated with the expansion suitability of the solid wafer are specified under temperature conditions at or near the temperature at which the expansion is actually performed.

The test pieces may have Eb's in 2 or more measurement directions the same as each other or different from each other. Here, "2 or more measurement directions of Eb'" means 2 or more different directions among directions parallel to the first surface of the test piece (corresponding to the first surface of the base material). For example, when the test piece has MD and TD, Eb 'of MD and Eb' of TD of the test piece may be the same or different from each other.

In the present embodiment, for example, the tensile elastic modulus Eb' of the test piece in any measurement direction may be any one of the 3 numerical ranges exemplified above. For example, when the test piece has MD and TD, Eb' may be any one of the 3 numerical value ranges exemplified above in either or both of MD and TD. In this case, the combination of the numerical range of Eb 'of MD and the numerical range of Eb' of TD is arbitrary.

The thickness of the test piece to be measured for the tensile elastic modulus Eb' is not particularly limited, and may be a thickness that allows the measurement to be performed with high accuracy. For example, the thickness of the test piece may be 10 to 200 μm.

The Eb' of the test piece made of the base material can be adjusted by adjusting the content of the base material, for example, the kind and content of the resin.

The optical properties of the base material are not particularly limited as long as the effects of the present invention are not impaired. The substrate may be, for example, a substrate that transmits laser light or energy rays.

The substrate can be produced by a known method. For example, a resin-containing (resin-constituting) substrate can be produced by molding the resin or a resin composition containing the resin.

< surface resistivity >

The surface resistivity of the surface of the solid-state wafer on the side opposite to the adhesive layer side of the substrate may be 1.0 × 10¹¹Omega/□ or less.

By using a base material having an antistatic layer formed thereon or an antistatic base material as the base material, the surface resistivity of the surface of the base material on the side opposite to the adhesive agent layer side can be made 1.0 × 10¹¹The details of Ω/□ will be described later.

The surface of the substrate on which the antistatic layer is formed on the side opposite to the adhesive layer side is sometimes referred to as "the outermost layer of the solid wafer". The surface of the antistatic base material on the side opposite to the adhesive agent layer side is sometimes referred to as "the outermost layer of the solid-state wafer".

Adhesive layer

The adhesive layer is in a sheet or film shape and contains an adhesive.

The adhesive layer can be formed using an adhesive composition containing the adhesive. For example, an adhesive composition is applied to a surface to be provided with an adhesive layer, and the applied surface is dried as needed, whereby the adhesive layer can be formed at a target site.

The adhesive composition may be applied by a known method, and examples thereof include a method using various coating machines such as a knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a curtain coater, a die coater, a knife coater, a screen coater, a meyer bar coater, and a kiss coater.

The drying conditions of the adhesive composition are not particularly limited, but when the adhesive composition contains a solvent described later, it is preferably dried by heating, and in this case, for example, it is preferably dried at 70 to 130 ℃ for 10 seconds to 5 minutes.

Examples of the adhesive include adhesive resins such as acrylic resins, urethane resins, rubber resins, silicone resins, epoxy resins, polyvinyl ethers, polycarbonates, and ester resins, and acrylic resins are preferred.

In the present specification, the term "adhesive resin" includes both a resin having adhesiveness and a resin having adhesiveness. For example, the adhesive resin includes not only a resin having adhesiveness of the resin itself but also a resin exhibiting adhesiveness by being used together with other components such as an additive, a resin exhibiting adhesiveness due to the presence of an inducer (trigger) such as heat or water, or the like.

The adhesive layer may be either curable or non-curable, and may be either energy ray-curable or non-energy ray-curable, for example. The curable adhesive layer can be easily adjusted in physical properties before and after curing.

In the present specification, the "energy ray" refers to a ray having an energy quantum in an electromagnetic wave or a charged particle beam. Examples of the energy ray include ultraviolet rays, radiation, and electron beams. For example, the ultraviolet rays can be irradiated by using a high-pressure mercury lamp, a fusion lamp (fusion lamp), a xenon lamp, a black light lamp, an LED lamp, or the like as an ultraviolet ray source. The electron beam can be irradiated with an electron beam generated by an electron beam accelerator or the like.

In the present specification, "energy ray-curable property" refers to a property of curing by irradiation with an energy ray, and "non-energy ray-curable property" refers to a property of not curing even by irradiation with an energy ray.

The adhesive layer may be composed of one layer (single layer) or a plurality of layers of two or more layers, and in the case of being composed of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

The thickness of the adhesive layer is preferably 1 to 100 μm, more preferably 1 to 60 μm, and particularly preferably 1 to 30 μm.

The "thickness of the adhesive agent layer" refers to the thickness of the entire adhesive agent layer, and for example, the thickness of the adhesive agent layer composed of a plurality of layers refers to the total thickness of all the layers constituting the adhesive agent layer.

The optical characteristics of the adhesive layer are not particularly limited as long as the effects of the present invention are not impaired. For example, the adhesive layer may be a layer that transmits energy rays.

Next, the adhesive composition will be described.

Adhesive composition

When the adhesive layer is energy ray-curable, examples of the adhesive composition containing an energy ray-curable adhesive, that is, an energy ray-curable adhesive composition, include: an adhesive composition (I-1) comprising an adhesive resin (I-1a) which is not curable by energy rays (hereinafter, sometimes abbreviated as "adhesive resin (I-1 a)") and an energy ray-curable compound; an adhesive composition (I-2) comprising an energy ray-curable adhesive resin (I-2a) (hereinafter, sometimes abbreviated as "adhesive resin (I-2 a)") having an unsaturated group introduced into a side chain of a non-energy ray-curable adhesive resin (I-1 a); and an adhesive composition (I-3) comprising the adhesive resin (I-2a) and an energy ray-curable compound.

< adhesive composition (I-1) >)

As described above, the adhesive composition (I-1) contains the non-energy ray-curable adhesive resin (I-1a) and the energy ray-curable compound.

[ adhesive resin (I-1a) ]

Preferably, the adhesive resin (I-1a) is an acrylic resin.

Examples of the acrylic resin include acrylic polymers having at least a structural unit derived from an alkyl (meth) acrylate.

The acrylic resin may have only one kind of structural unit, or two or more kinds of structural units, and in the case of two or more kinds of structural units, the combination and ratio thereof may be arbitrarily selected.

The adhesive resin (I-1a) contained in the adhesive composition (I-1) may be one type or two or more types, and when two or more types are used, the combination and ratio thereof may be arbitrarily selected.

In the adhesive composition (I-1), the content of the adhesive resin (I-1a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass, based on the total mass of the adhesive composition (I-1).

[ energy ray-curable Compound ]

Examples of the energy ray-curable compound contained in the adhesive composition (I-1) include a monomer or oligomer having an energy ray-polymerizable unsaturated group and curable by irradiation with an energy ray.

Examples of the monomer in the energy ray-curable compound include polyvalent (meth) acrylates such as trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1, 4-butanediol di (meth) acrylate, and 1, 6-hexanediol (meth) acrylate; urethane (meth) acrylate; polyester (meth) acrylates; polyether (meth) acrylates; epoxy (meth) acrylates, and the like.

Examples of the oligomer in the energy ray-curable compound include oligomers obtained by polymerizing the monomers exemplified above.

The energy ray-curable compound is preferably a urethane (meth) acrylate or a urethane (meth) acrylate oligomer in terms of a large molecular weight and a low tendency to decrease the storage modulus of the adhesive agent layer.

The energy ray-curable compound contained in the adhesive composition (I-1) may be only one kind, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

In the adhesive composition (I-1), the content of the energy ray-curable compound is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass, based on the total mass of the adhesive composition (I-1).

[ crosslinking agent ]

When the acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to a structural unit derived from an alkyl (meth) acrylate is used as the adhesive resin (I-1a), it is preferable that the adhesive composition (I-1) further contains a crosslinking agent.

The crosslinking agent crosslinks the adhesive resins (I-1a) to each other, for example, by reacting with the functional groups.

Examples of the crosslinking agent include isocyanate-based crosslinking agents (crosslinking agents having an isocyanate group) such as toluene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; epoxy crosslinking agents (crosslinking agents having a glycidyl group) such as ethylene glycol glycidyl ether; aziridine crosslinking agents (crosslinking agents having an aziridinyl group) such as hexa [1- (2-methyl) -azidinyl ] triphosphazine (hexa); metal chelate crosslinking agents (crosslinking agents having a metal chelate structure) such as aluminum chelate; an isocyanurate-based crosslinking agent (a crosslinking agent having an isocyanurate skeleton), and the like.

The crosslinking agent is preferably an isocyanate-based crosslinking agent from the viewpoint of improving the cohesive force of the adhesive agent to thereby improve the adhesive force of the adhesive agent layer, and from the viewpoint of easy availability.

The crosslinking agent contained in the adhesive composition (I-1) may be one kind only, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When a crosslinking agent is used, the content of the crosslinking agent in the adhesive composition (I-1) is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, and particularly preferably 0.3 to 15 parts by mass, based on 100 parts by mass of the content of the adhesive resin (I-1 a).

[ photopolymerization initiator ]

The adhesive composition (I-1) may further contain a photopolymerization initiator. Even when the adhesive composition (I-1) containing a photopolymerization initiator is irradiated with a relatively low energy ray such as ultraviolet ray, the curing reaction proceeds sufficiently.

Examples of the photopolymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, and benzoin dimethyl ketal; acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 2, 2-dimethoxy-1, 2-diphenylethan-1-one; acylphosphine oxide compounds such as phenylbis (2,4, 6-trimethylbenzoyl) phosphine oxide and 2,4, 6-trimethylbenzoyl diphenylphosphine oxide; sulfides such as benzyl phenyl sulfide and tetramethylthiuram monosulfide; α -ketol compounds such as 1-hydroxycyclohexyl phenyl ketone; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; thioxanthone compounds such as thioxanthone; a peroxide compound; diketone compounds such as butanedione; benzil; dibenzoyl; benzophenone; 2, 4-diethylthioxanthone; 1, 2-diphenylmethane; 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl ] propanone; 2-chloroanthraquinone, and the like.

Further, as the photopolymerization initiator, for example, quinone compounds such as 1-chloroanthraquinone; photosensitizers such as amines, and the like.

The photopolymerization initiator contained in the pressure-sensitive adhesive composition (I-1) may be only one kind, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When a photopolymerization initiator is used, the content of the photopolymerization initiator in the adhesive composition (I-1) is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, relative to 100 parts by mass of the content of the energy ray-curable compound.

[ other additives ]

The adhesive composition (I-1) may further contain other additives not included in any of the above components within a range not impairing the effects of the present invention.

Examples of the other additives include known additives such as antistatic agents, antioxidants, softeners (plasticizers), fillers (fillers), rust inhibitors, colorants (pigments and dyes), sensitizers, tackifiers, reaction retarders, and crosslinking accelerators (catalysts).

The reaction retarder is, for example, a component for suppressing unintended crosslinking reaction in the adhesive composition (I-1) during storage due to the action of the catalyst mixed in the adhesive composition (I-1). Examples of the reaction retarder include a reaction retarder which forms a chelate complex (chelate complex) by a chelate compound corresponding to a catalyst, and more specifically, a reaction retarder having two or more carbonyl groups (-C (═ O) -) in one molecule.

The adhesive composition (I-1) may contain only one other additive, or may contain two or more other additives, and when two or more other additives are contained, the combination and ratio of these additives may be arbitrarily selected.

The content of the other additives in the adhesive composition (I-1) is not particularly limited, and may be appropriately selected depending on the kind thereof.

[ solvent ]

The adhesive composition (I-1) may contain a solvent. By containing the solvent, the applicability of the adhesive composition (I-1) to the surface to be coated is improved.

The solvent is preferably an organic solvent.

< adhesive composition (I-2) >)

As described above, the adhesive composition (I-2) contains the energy ray-curable adhesive resin (I-2a) in which an unsaturated group is introduced into the side chain of the non-energy ray-curable adhesive resin (I-1 a).

[ adhesive resin (I-2a) ]

The adhesive resin (I-2a) is obtained, for example, by reacting an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group with a functional group in the adhesive resin (I-1 a).

The unsaturated group-containing compound is a compound having a group that can be bonded to the adhesive resin (I-1a) by reacting with a functional group in the adhesive resin (I-1a), in addition to the energy ray-polymerizable unsaturated group.

Examples of the energy ray-polymerizable unsaturated group include a (meth) acryloyl group, a vinyl group (ethylene group), and an allyl group (2-propenyl group), and a (meth) acryloyl group is preferable.

Examples of the group that can be bonded to the functional group in the adhesive resin (I-1a) include an isocyanate group and a glycidyl group that can be bonded to a hydroxyl group or an amino group, and a hydroxyl group and an amino group that can be bonded to a carboxyl group or an epoxy group.

Examples of the unsaturated group-containing compound include (meth) acryloyloxyethyl isocyanate, (meth) acryloyl isocyanate, and glycidyl (meth) acrylate.

The adhesive resin (I-2a) contained in the adhesive composition (I-2) may be one type or two or more types, and when two or more types are used, the combination and ratio thereof may be arbitrarily selected.

In the adhesive composition (I-2), the content of the adhesive resin (I-2a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 10 to 90% by mass, based on the total mass of the adhesive composition (I-2).

[ crosslinking agent ]

For example, when the same acrylic polymer having a structural unit derived from a functional group-containing monomer as in the adhesive resin (I-1a) is used as the adhesive resin (I-2a), the adhesive composition (I-2) may further contain a crosslinking agent.

The crosslinking agent in the adhesive composition (I-2) may be the same crosslinking agent as that in the adhesive composition (I-1).

The crosslinking agent contained in the adhesive composition (I-2) may be one kind only, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

When a crosslinking agent is used, the content of the crosslinking agent in the adhesive composition (I-2) is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, and particularly preferably 0.3 to 15 parts by mass, relative to 100 parts by mass of the content of the adhesive resin (I-2 a).

[ photopolymerization initiator ]

The adhesive composition (I-2) may further contain a photopolymerization initiator. Even when the adhesive composition (I-2) containing a photopolymerization initiator is irradiated with a relatively low energy ray such as ultraviolet ray, the curing reaction proceeds sufficiently.

The photopolymerization initiator in the adhesive composition (I-2) may be the same photopolymerization initiator as that in the adhesive composition (I-1).

The photopolymerization initiator contained in the pressure-sensitive adhesive composition (I-2) may be only one kind, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When a photopolymerization initiator is used, the content of the photopolymerization initiator in the adhesive composition (I-2) is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, relative to 100 parts by mass of the content of the adhesive resin (I-2 a).

[ other additives and solvents ]

The adhesive composition (I-2) may further contain other additives not included in any of the above components within a range not impairing the effects of the present invention.

Further, the adhesive composition (I-2) may also contain a solvent for the same purpose as the adhesive composition (I-1).

Examples of the other additives and solvents in the adhesive composition (I-2) include the same additives and solvents as those in the adhesive composition (I-1). The other additives and solvents contained in the adhesive composition (I-2) may be one type or two or more types, and when two or more types are contained, the combination and ratio thereof may be arbitrarily selected.

The contents of other additives and solvents in the adhesive composition (I-2) are not particularly limited, and may be appropriately selected depending on the type thereof.

< adhesive composition (I-3) >)

As described above, the adhesive composition (I-3) contains the adhesive resin (I-2a) and an energy ray-curable compound.

In the adhesive composition (I-3), the content of the adhesive resin (I-2a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass, based on the total mass of the adhesive composition (I-3).

[ energy ray-curable Compound ]

Examples of the energy ray-curable compound contained in the adhesive composition (I-3) include monomers and oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with an energy ray, and examples of the energy ray-curable compound include the same energy ray-curable compounds as those contained in the adhesive composition (I-1).

The energy ray-curable compound contained in the adhesive composition (I-3) may be only one kind, or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The content of the energy ray-curable compound in the adhesive composition (I-3) is preferably 0.01 to 300 parts by mass, more preferably 0.03 to 200 parts by mass, and particularly preferably 0.05 to 100 parts by mass, relative to 100 parts by mass of the content of the adhesive resin (I-2 a).

[ photopolymerization initiator ]

The adhesive composition (I-3) may further contain a photopolymerization initiator. Even when the adhesive composition (I-3) containing a photopolymerization initiator is irradiated with a relatively low energy ray such as ultraviolet ray, the curing reaction proceeds sufficiently.

The photopolymerization initiator in the adhesive composition (I-3) may be the same photopolymerization initiator as that in the adhesive composition (I-1).

The photopolymerization initiator contained in the pressure-sensitive adhesive composition (I-3) may be only one kind, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When a photopolymerization initiator is used, the content of the photopolymerization initiator in the adhesive composition (I-3) is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the total content of the adhesive resin (I-2a) and the energy ray-curable compound.

[ other additives and solvents ]

The adhesive composition (I-3) may further contain other additives not included in any of the above components within a range not impairing the effects of the present invention.

Further, the adhesive composition (I-3) may also contain a solvent for the same purpose as the adhesive composition (I-1).

Examples of the other additives and solvents in the adhesive composition (I-3) include the same additives and solvents as those in the adhesive composition (I-1). The adhesive composition (I-3) may contain only one type of other additive and solvent, or two or more types of other additives and solvents, and when two or more types are contained, the combination and ratio of these may be arbitrarily selected.

The contents of other additives and solvents in the adhesive composition (I-3) are not particularly limited, and may be appropriately selected depending on the type thereof.

< adhesive compositions other than the adhesive compositions (I-1) to (I-3) >

Although the adhesive composition (I-1), the adhesive composition (I-2) and the adhesive composition (I-3) have been mainly described so far, the components described as the components contained therein can be similarly used in all adhesive compositions other than the three adhesive compositions (in the present specification, referred to as "adhesive compositions other than the adhesive compositions (I-1) to (I-3)").

Examples of the adhesive compositions other than the adhesive compositions (I-1) to (I-3) include energy ray-curable adhesive compositions and non-energy ray-curable adhesive compositions.

Examples of the non-energy ray-curable adhesive composition include an adhesive composition (I-4) containing a non-energy ray-curable adhesive resin (I-1a) such as an acrylic resin, a urethane resin, a rubber resin, a silicone resin, an epoxy resin, a polyvinyl ether, a polycarbonate, or an ester resin, and a non-energy ray-curable adhesive composition containing an acrylic resin is preferable.

The adhesive compositions other than the adhesive compositions (I-1) to (I-3) preferably contain one or more kinds of crosslinking agents, and the content thereof may be set to the same level as that of the adhesive composition (I-1).

< adhesive composition (I-4) >)

A preferable adhesive composition (I-4) includes, for example, an adhesive composition containing the adhesive resin (I-1a) and a crosslinking agent.

[ adhesive resin (I-1a) ]

The adhesive resin (I-1a) in the adhesive composition (I-4) may be the same adhesive resin (I-1a) as the adhesive resin (I-1a) in the adhesive composition (I-1).

The adhesive resin (I-1a) contained in the adhesive composition (I-4) may be one type or two or more types, and when two or more types are used, the combination and ratio thereof may be arbitrarily selected.

In the adhesive composition (I-4), the content of the adhesive resin (I-1a) is preferably 5 to 99% by mass, more preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass, based on the total mass of the adhesive composition (I-4).

[ crosslinking agent ]

When the acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to a structural unit derived from an alkyl (meth) acrylate is used as the adhesive resin (I-1a), it is preferable that the adhesive composition (I-4) further contains a crosslinking agent.

The crosslinking agent in the adhesive composition (I-4) may be the same crosslinking agent as that in the adhesive composition (I-1).

The crosslinking agent contained in the adhesive composition (I-4) may be one kind only, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

In the adhesive composition (I-4), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 25 parts by mass, and particularly preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the content of the adhesive resin (I-1 a).

[ other additives and solvents ]

The adhesive composition (I-4) may further contain other additives not included in any of the above components within a range not impairing the effects of the present invention.

Further, the adhesive composition (I-4) may also contain a solvent for the same purpose as the adhesive composition (I-1).

Examples of the other additives and solvents in the adhesive composition (I-4) include the same additives and solvents as those in the adhesive composition (I-1). The adhesive composition (I-4) may contain only one type of other additive and solvent, or two or more types of other additives and solvents, and when two or more types are contained, the combination and ratio of these additives and solvents can be arbitrarily selected.

The contents of other additives and solvents in the adhesive composition (I-4) are not particularly limited, and may be appropriately selected depending on the type thereof.

Preparation method of adhesive composition

The adhesive compositions other than the adhesive compositions (I-1) to (I-3), such as the adhesive compositions (I-1) to (I-3) and the adhesive composition (I-4), can be obtained by blending the components constituting the adhesive compositions, that is, the adhesive and, if necessary, components other than the adhesive.

The order of addition of the components in blending is not particularly limited, and two or more components may be added simultaneously.

When a solvent is used, the solvent may be mixed with any of the components other than the solvent to preliminarily dilute the components, or the solvent may be mixed with the components without preliminarily diluting any of the components other than the solvent to use the mixture.

The method for mixing the components at the time of blending is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by rotating a stirrer, a stirring blade, or the like; a method of mixing using a mixer (mixer); a method of mixing by applying ultrasonic waves, and the like.

The temperature and time when the components are added and mixed are not particularly limited as long as the components are not deteriorated, and may be appropriately adjusted, but the temperature is preferably 15 to 30 ℃.

Intermediate layer

The intermediate layer is in a sheet or film shape and contains a resin.

The intermediate layer may be made of a resin, or may contain a resin and a component other than the resin.

The intermediate layer can be formed, for example, by molding the resin or the intermediate layer-forming composition containing the resin. The intermediate layer may be formed by applying the intermediate layer-forming composition to the surface to be formed of the intermediate layer and drying the composition as necessary.

The resin as a constituent material of the intermediate layer is not particularly limited.

Examples of the preferable resin in the intermediate layer include ethylene-vinyl acetate copolymer (EVA), polypropylene (PP), Polyethylene (PE), and Urethane Acrylate (UA).

The content of the resin in the intermediate layer-forming composition is not particularly limited, and may be, for example, 80 mass% or more, 90 mass% or more, 95 mass% or more, or the like, but this is merely an example.

The intermediate layer may be composed of one layer (single layer) or a plurality of layers of two or more layers, and in the case of being composed of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

< shear elastic modulus Ei' of test piece made of intermediate layer >

When a tensile test in which a test piece having a width of 15mm and a length of more than 100mm, which is produced from an intermediate layer (the intermediate layer 13 in the case of the fixed wafer 101 shown in fig. 1), is stretched at a stretching speed of 200mm/min is performed using TENSILON with a collet pitch of 100mm and a temperature of 0 ℃, and a tensile elastic modulus Ei 'of the test piece at 0 ℃ in an elastic deformation region is measured, Ei' may be any one of, for example, 10 to 150MPa, 10 to 100MPa, and 10 to 50 MPa. By making Ei ' in the above range, the tensile elastic modulus becomes easier to adjust than Ei '/Eb '.

In the above-mentioned solid-state wafer, the tensile elastic modulus Ei 'of the test piece made of the intermediate layer was also defined as a value at 0 ℃ for the same reason as Eb'.

The test pieces may have the same or different Ei's in 2 or more measurement directions. Here, "2 or more measurement directions of Ei" means 2 or more different directions among directions parallel to the first surface of the test piece (corresponding to the first surface of the intermediate layer). For example, when the test piece has MD and TD, Ei 'of MD and Ei' of TD of the test piece may be the same or different from each other.

In the present embodiment, for example, the tensile elastic modulus Ei' of the test piece in any measurement direction may be any one of the 3 numerical ranges exemplified above. For example, when the test piece has MD and TD, Ei' may be any of the 3 numerical value ranges exemplified above in either or both of MD and TD. In this case, the combination of the numerical range of Ei 'of MD and the numerical range of Ei' of TD is arbitrary.

The thickness of the test piece to be measured for the tensile elastic modulus Ei' is not particularly limited, and may be a thickness that allows the measurement to be performed with high accuracy. For example, the thickness of the test piece may be 10 to 200 μm.

The Ei' of the test piece made of the intermediate layer can be adjusted by adjusting the content of the intermediate layer, for example, the kind and content of the resin.

< tensile elastic modulus ratio Ei '/Eb' >

In the present embodiment, the tensile elastic modulus ratio Ei '/Eb' calculated using the tensile elastic modulus Eb 'of the test piece made of the base material and the tensile elastic modulus Ei' of the test piece made of the intermediate layer is 0.5 or less, and may be any one of 0.45 or less, 0.4 or less, and 0.35 or less, for example. When the tensile elastic modulus ratio Ei '/Eb' is equal to or less than the upper limit value, the slit width becomes sufficiently wide with respect to the elongation of the base material when the fixed wafer is expanded, and the film-like adhesive can be stably cut (divided) along the outer periphery of the semiconductor chip.

As described above, Eb 'and Ei' may be different in the measurement direction of the test piece to be measured (the test piece of the base material in the case of Eb 'and the test piece of the intermediate layer in the case of Ei'). In the present embodiment, as Ei 'and Eb' used for the calculation of the tensile elastic modulus ratio Ei '/Eb', Ei 'and Eb' reflecting the arrangement direction of the base material and the intermediate layer in the solid wafer are used.

For example, when both the test piece of the base material and the test piece of the intermediate layer have MD and TD, and the MD of the base material and the MD of the intermediate layer in the fixed wafer coincide (in other words, the TD of the base material and the TD of the intermediate layer coincide), the tensile elastic modulus ratio Ei '/Eb' is 0.5 or less, for example, 0.45 or less, 0.4 or less, or 0.35 or less in either or both of the MD and TD. In this case, the combination of the numerical range of Ei '/Eb' of MD and the numerical range of Ei '/Eb' of TD is arbitrary.

The lower limit of the tensile elastic modulus ratio Ei '/Eb' is not particularly limited as long as it is greater than 0. For example, the tensile elastic modulus ratio Ei '/Eb' may be 0.05 or more from the viewpoint of calculation from a combination of 200MPa, which is one example of the preferred upper limit value of Eb ', and 10MPa, which is one example of the preferred lower limit value of Ei'.

The tensile modulus ratio Ei '/Eb' can be adjusted as appropriate within a range set by arbitrarily combining the above lower limit value and upper limit value. For example, in one embodiment, the tensile modulus of elasticity ratio Ei '/Eb' may be any one of 0.05 to 0.5, 0.05 to 0.45, 0.05 to 0.4, and 0.05 to 0.35.

When both the test piece of the base material and the test piece of the intermediate layer have MD and TD, and the MD of the base material and the MD of the intermediate layer coincide with each other in the fixed wafer (in other words, the TD of the base material and the TD of the intermediate layer coincide with each other), the tensile elastic modulus ratio Ei '/Eb' is 0.5 or less in either or both of the MD and TD, and may be any one of 0.05 to 0.5, 0.05 to 0.45, 0.05 to 0.4, and 0.05 to 0.35. In this case, the combination of the numerical range of Ei '/Eb' of MD and the numerical range of Ei '/Eb' of TD is arbitrary.

As explained hereinbefore, the maximum value of the width of the intermediate layer is smaller than the maximum value of the width of the adhesive layer and the maximum value of the width of the substrate.

The maximum value of the width of the intermediate layer may be appropriately selected in consideration of the size of the semiconductor wafer. For example, the maximum value of the width of the intermediate layer may be 150 to 160mm, 200 to 210mm, or 300 to 310 mm. These three numerical ranges correspond to semiconductor wafers having a maximum value of width in a direction parallel to the surface to which the die is attached of 150mm, 200mm, or 300 mm. In the present embodiment, as described above, the die bond sheet is attached to the semiconductor wafer after dicing. The "semiconductor wafer after dicing" is synonymous with the "semiconductor chip group" described later.

In this specification, unless otherwise specified, "the width of the intermediate layer" means, for example, "the width in the direction parallel to the first face of the intermediate layer". For example, in the case of an intermediate layer having a circular planar shape, the maximum value of the width of the intermediate layer is the diameter of a circle having the planar shape.

This is also the case for semiconductor wafers. That is, the "width of the semiconductor wafer" refers to the above-mentioned "width of the semiconductor wafer in the direction parallel to the surface thereof to which the die is attached". For example, in the case of a semiconductor wafer having a circular planar shape, the maximum value of the width of the semiconductor wafer is the diameter of a circle having the planar shape.

The maximum value of the width of the intermediate layer of 150 to 160mm is equal to or greater than the maximum value of the width of the semiconductor wafer of 150mm in a range of not more than 10 mm.

Similarly, the maximum value of the width of the intermediate layer of 200 to 210mm is equal to or greater than the maximum value of the width of the semiconductor wafer of 200mm in a range of not more than 10 mm.

Similarly, the maximum value of the width of the intermediate layer of 300 to 310mm is equal to or greater than the maximum value of the width of the semiconductor wafer of 300mm in a range of not more than 10 mm.

That is, in the present embodiment, the difference between the maximum value of the width of the intermediate layer and the maximum value of the width of the semiconductor wafer may be, for example, 0to 10mm, regardless of which value of 150mm, 200mm and 300mm the maximum value of the width of the semiconductor wafer is.

When the maximum value of the width of the intermediate layer satisfies the above condition, the effect of suppressing the film-like adhesive after the cutting other than the generation of the adhesive after the cutting becomes high when the film-like adhesive is cut by the spreading of the solid-state sheet.

The thickness of the intermediate layer may be appropriately selected according to the purpose, but is preferably 20 to 150 μm, and more preferably 50 to 120 μm. By making the thickness of the intermediate layer more than the lower limit value, the structure of the intermediate layer is more stable. By setting the thickness of the intermediate layer to the upper limit or less, the cuttability of the film-like adhesive is further improved when the die is expanded. Further, when the fixed wafer after cutting the film-like adhesive is spread (in other words, when the laminated sheet is spread), the effect of making the slit width sufficiently wide and maintaining the slit width with high uniformity is further increased.

Here, the "thickness of the intermediate layer" refers to the thickness of the entire intermediate layer, and for example, the thickness of the intermediate layer composed of a plurality of layers refers to the total thickness of all layers constituting the intermediate layer.

The intermediate layer is preferably softer than the substrate. For example, an intermediate layer having an Ei 'smaller than Eb' (Ei '< Eb') satisfies this condition, and as an intermediate layer more preferable from such a viewpoint, as described above, an intermediate layer having a tensile elastic modulus ratio Ei '/Eb' of 0.5 or less is exemplified.

Film-like adhesive

The film-like adhesive has curability, preferably has thermosetting property, and preferably has pressure-sensitive adhesiveness. A film-like adhesive having both thermosetting and pressure-sensitive adhesiveness can be attached to various adherends by lightly pressing in an uncured state. The film-like adhesive may be an adhesive capable of being attached to various adherends by softening the adhesive by heating. The film-like adhesive is cured to finally form a cured product having high impact resistance, and the cured product can maintain sufficient adhesive properties even under severe conditions of high temperature and high humidity.

When the die is viewed from above in a downward direction, the area of the film-like adhesive (i.e., the area of the first surface) is preferably set to be smaller than the area of the base material (i.e., the area of the first surface) and the area of the adhesive layer (i.e., the area of the first surface) so as to be close to the area of the semiconductor wafer before dicing. In such a die bonding sheet, a region not in contact with the film-like adhesive exists in a part of the first surface of the adhesive layer. This makes it easier to expand the solid-state sheet, and the force applied to the film-like adhesive during expansion is not dispersed, so that the film-like adhesive is more easily cut.

The film-like adhesive can be formed using an adhesive composition containing the constituent materials thereof. For example, a film-like adhesive can be formed at a target site by applying an adhesive composition to a surface to be formed with the film-like adhesive and drying the adhesive composition as needed.

The application of the adhesive composition can be performed by the same method as the application of the adhesive composition described above.

The drying conditions of the adhesive composition are not particularly limited. When the binder composition contains a solvent described later, it is preferably dried by heating, and in this case, it is preferably dried at 70 to 130 ℃ for 10 seconds to 5 minutes, for example.

The film-like adhesive may be composed of one layer (single layer) or a plurality of layers of two or more layers, and in the case of being composed of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

As explained hereinbefore, the maximum value of the width of the film-like adhesive is smaller than the maximum value of the width of the adhesive layer and the maximum value of the width of the base material.

The maximum value of the width of the film-like adhesive may be the same as the maximum value of the width of the intermediate layer explained above with respect to the size of the semiconductor wafer.

That is, the maximum value of the width of the film-like adhesive can be appropriately selected in consideration of the size of the semiconductor wafer. For example, the maximum value of the width of the film-like adhesive may be 150 to 160mm, 200 to 210mm, or 300 to 310 mm. These three numerical ranges correspond to semiconductor wafers having a maximum value of width in a direction parallel to the surface to which the die is attached of 150mm, 200mm, or 300 mm.

In the present specification, unless otherwise specified, "width of film-like adhesive" means, for example, that

"width of the film-like adhesive in a direction parallel to the first face of the film-like adhesive". For example, in the case of a film-like adhesive having a circular planar shape, the maximum value of the width of the film-like adhesive is the diameter of a circle having the planar shape.

In addition, unless otherwise specified, "the width of the film-like adhesive" means "the width of the film-like adhesive before cutting (not cutting)" and is not the width of the film-like adhesive after cutting in the manufacturing process of the semiconductor chip with the film-like adhesive described later.

The maximum value of the width of the film-like adhesive of 150 to 160mm means the maximum value of the width of a semiconductor wafer which is equal to or larger than 150mm within a range of not more than 10 mm.

The maximum value of the width of the film-like adhesive of 200 to 210mm is equal to or larger than the maximum value of the width of a semiconductor wafer of 200mm in a range of not more than 10 mm.

Similarly, the maximum value of the width of the film-like adhesive of 300 to 310mm means the maximum value of the width of a semiconductor wafer which is equal to or larger than 300mm in a range of not more than 10 mm.

That is, in the present embodiment, the difference between the maximum value of the width of the film-like adhesive and the maximum value of the width of the semiconductor wafer may be, for example, 0to 10mm, regardless of which value of 150mm, 200mm and 300mm the maximum value of the width of the semiconductor wafer is.

When the maximum value of the width of the film-like adhesive satisfies the above-described condition, the effect of suppressing the film-like adhesive from scattering other than the generation of the film-like adhesive after the cutting described later when the film-like adhesive is cut by spreading of the solid-state sheet becomes high.

In the present embodiment, the maximum value of the width of the intermediate layer and the maximum value of the width of the film-like adhesive may be any one of the above numerical value ranges.

That is, as an example of the die bonding sheet of the present embodiment, a die bonding sheet in which the maximum value of the width of the intermediate layer and the maximum value of the width of the film-like adhesive are 150 to 160mm, 200 to 210mm, or 300 to 310mm can be mentioned.

The thickness of the film-like adhesive is not particularly limited, but is preferably 1 to 30 μm, more preferably 2 to 20 μm, and particularly preferably 3 to 10 μm. By setting the thickness of the film-like pressure-sensitive adhesive to the lower limit or more, a higher adhesive force to an adherend (semiconductor chip) can be obtained. When the thickness of the film-shaped adhesive is not more than the upper limit, the cutting property of the spread film-shaped adhesive is further improved, and the amount of the cut pieces derived from the film-shaped adhesive can be further reduced.

The "thickness of the film-like adhesive" refers to the thickness of the entire film-like adhesive, and for example, the thickness of the film-like adhesive composed of a plurality of layers refers to the total thickness of all the layers constituting the film-like adhesive.

Next, the adhesive composition will be described.

Adhesive composition

A preferable adhesive composition includes, for example, an adhesive composition containing a polymer component (a) and a thermosetting component (b). Hereinafter, each component will be described.

In addition, the adhesive composition shown below is one example of a preferable adhesive composition, and the adhesive composition of the present embodiment is not limited to the adhesive composition shown below.

[ Polymer component (a) ]

The polymer component (a) can be considered as a component formed by polymerizing a polymerizable compound, which is a polymer compound for imparting film formability, flexibility, or the like to a film-like adhesive and simultaneously improving adhesiveness (in other words, adhesiveness) to an object to be adhered such as a semiconductor chip. The polymer component (a) is also a component that does not belong to the epoxy resin (b1) and the thermosetting agent (b2) described later.

The polymer component (a) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

Examples of the polymer component (a) include acrylic resins, urethane resins, phenoxy resins, silicone resins, and saturated polyester resins, and acrylic resins are preferred.

In the adhesive composition, the proportion of the content of the polymer component (a) to the total content of all components except the solvent (i.e., the proportion of the content of the polymer component (a) in the film-shaped adhesive to the total mass of the film-shaped adhesive) is preferably 20 to 75 mass%, more preferably 30 to 65 mass%.

[ thermosetting component (b) ]

The thermosetting component (b) is a component having thermosetting properties for thermosetting the film-like adhesive.

The thermosetting component (b) is composed of an epoxy resin (b1) and a thermosetting agent (b 2).

The thermosetting component (b) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

Epoxy resin (b1)

Examples of the epoxy resin (b1) include known epoxy resins, and examples thereof include polyfunctional epoxy resins, biphenyl compounds, bisphenol a diglycidyl ether and hydrogenated products thereof, o-cresol novolac (novolak) epoxy resins, dicyclopentadiene epoxy resins, biphenyl epoxy resins, bisphenol a epoxy resins, bisphenol F epoxy resins, and epoxy resins having a phenylene skeleton.

As the epoxy resin (b1), an epoxy resin having an unsaturated hydrocarbon group can also be used. The compatibility of the epoxy resin having an unsaturated hydrocarbon group with the acrylic resin is greater than the compatibility of the epoxy resin having no unsaturated hydrocarbon group with the acrylic resin. Therefore, by using the epoxy resin having an unsaturated hydrocarbon group, the reliability of the package obtained by using the film-like adhesive is improved.

The epoxy resin (b1) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

Heat-curing agent (b2)

The thermosetting agent (b2) functions as a curing agent for the epoxy resin (b 1).

Examples of the thermosetting agent (b2) include compounds having two or more functional groups reactive with epoxy groups in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and a group obtained by anhydrizing an acid group, and the like, and preferably a phenolic hydroxyl group, an amino group, or a group obtained by anhydrizing an acid group, and the like, and more preferably a phenolic hydroxyl group or an amino group.

Examples of the phenol curing agent having a phenolic hydroxyl group in the heat curing agent (b2) include polyfunctional phenol resins, biphenol, novolak-type phenol resins, dicyclopentadiene-type phenol resins, and aralkyl-type phenol resins.

Examples of the amine-based curing agent having an amino group in the thermosetting agent (b2) include Dicyandiamide (DICY).

The thermosetting agent (b2) may have an unsaturated hydrocarbon group.

The heat-curing agent (b2) contained in the adhesive composition and the film-like adhesive may be one type or two or more types, and when two or more types are used, the combination and ratio thereof may be arbitrarily selected.

In the adhesive composition and the film-like adhesive, the content of the thermosetting agent (b2) is preferably 0.1 to 500 parts by mass, more preferably 1 to 200 parts by mass, and may be any of 1 to 100 parts by mass, 1 to 50 parts by mass, and 1 to 25 parts by mass, for example, with respect to 100 parts by mass of the content of the epoxy resin (b 1). When the content of the thermosetting agent (b2) is not less than the lower limit value, the film-like adhesive can be more easily cured. When the content of the thermosetting agent (b2) is not more than the upper limit, the moisture absorption rate of the film-like adhesive is reduced, and the reliability of the package obtained by using the film-like adhesive is further improved.

In the adhesive composition and the film-like adhesive, the content of the thermosetting component (b) (i.e., the total content of the epoxy resin (b1) and the thermosetting agent (b 2)) is preferably 5 to 100 parts by mass, more preferably 5 to 75 parts by mass, particularly preferably 5 to 50 parts by mass, and may be, for example, 5 to 35 parts by mass or 5 to 20 parts by mass, relative to 100 parts by mass of the content of the polymer component (a). By setting the content of the thermosetting component (b) to the above range, the peeling force between the intermediate layer and the film-shaped adhesive is more stabilized.

In order to improve various physical properties of the film-shaped adhesive, the film-shaped adhesive may further contain, in addition to the polymer component (a) and the thermosetting component (b), other components not belonging to the polymer component (a) and the thermosetting component (b) as required.

Preferable examples of the other components contained in the film-like adhesive include a curing accelerator (c), a filler (d), a coupling agent (e), a crosslinking agent (f), an energy ray-curable resin (g), a photopolymerization initiator (h), and a general-purpose additive (i).

[ curing Accelerator (c) ]

The curing accelerator (c) is a component for adjusting the curing speed of the adhesive composition.

Examples of the preferable curing accelerator (c) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; imidazoles (imidazole in which one or more hydrogen atoms are replaced with a group other than a hydrogen atom) such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4, 5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; organic phosphines such as tributylphosphine, diphenylphosphine, and triphenylphosphine (phosphines in which one or more hydrogen atoms are substituted with an organic group); tetraphenylboron salts such as tetraphenylphosphonium tetraphenylphosphonate and triphenylphosphine tetraphenylboronate.

The curing accelerator (c) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When the curing accelerator (c) is used, the content of the curing accelerator (c) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the thermosetting component (b) in the adhesive composition and the film-like adhesive. By setting the content of the curing accelerator (c) to the lower limit or more, the effect of using the curing accelerator (c) can be more remarkably obtained. When the content of the curing accelerator (c) is not more than the above upper limit, for example, the effect of suppressing the migration of the highly polar curing accelerator (c) to the side of the adhesive interface with the adherend in the film-like adhesive under high temperature and high humidity conditions and the occurrence of segregation increases, and the reliability of the package obtained using the film-like adhesive is further improved.

[ Filler (d) ]

By containing the filler (d) in the film-like adhesive, the cuttability by the spread film-like adhesive is further improved. Further, by containing the filler (d) in the film-like adhesive, the thermal expansion coefficient of the film-like adhesive can be easily adjusted, and by optimizing the thermal expansion coefficient with respect to the object to which the film-like adhesive is attached, the reliability of the package obtained by using the film-like adhesive can be further improved. Further, by containing the filler (d) in the film-shaped adhesive, the moisture absorption rate of the cured film-shaped adhesive can be reduced or the heat dissipation property can be improved.

The filler (d) may be any of an organic filler and an inorganic filler, and is preferably an inorganic filler.

Examples of preferable inorganic fillers include powders of silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride, and the like; beads (beads) obtained by spheroidizing these inorganic fillers; surface modifications of these inorganic filler materials; single crystal fibers of these inorganic filler materials; glass fibers, and the like.

Among them, the inorganic filler is preferably silica or alumina.

The filler (d) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When the filler (d) is used, the content of the filler (d) in the adhesive composition is preferably 5 to 80% by mass, more preferably 10 to 70% by mass, and particularly preferably 20 to 60% by mass, based on the total content of all the components except the solvent (i.e., the content of the filler (d) in the film-shaped adhesive based on the total mass of the film-shaped adhesive). By setting the ratio to the above range, the effect of using the filler (d) can be more remarkably obtained.

[ coupling agent (e) ]

When the film-shaped pressure-sensitive adhesive contains the coupling agent (e), the adhesiveness to an adherend and the adhesion are improved. Further, by incorporating the coupling agent (e) into the film-shaped adhesive, the water resistance of the cured product of the film-shaped adhesive is improved without impairing the heat resistance. The coupling agent (e) has a functional group reactive with an inorganic compound or an organic compound.

The coupling agent (e) is preferably a compound having a functional group capable of reacting with the functional group of the polymer component (a), the thermosetting component (b), or the like, and more preferably a silane coupling agent.

The coupling agent (e) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When the coupling agent (e) is used, the content of the coupling agent (e) is preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and particularly preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the total content of the polymer component (a) and the thermosetting component (b) in the adhesive composition and the film-like adhesive. When the content of the coupling agent (e) is not less than the lower limit, the effects of using the coupling agent (e), that is, the improvement of the dispersibility of the filler (d) in the resin, the improvement of the adhesiveness between the film-shaped adhesive and the adherend, and the like can be more remarkably obtained. By making the content of the coupling agent (e) the upper limit value or less, the generation of outgas (outgas) can be further suppressed.

[ crosslinking agent (f) ]

When a substance having a functional group such as a vinyl group, (meth) acryloyl group, amino group, hydroxyl group, carboxyl group, or isocyanate group, which can be bonded to another compound, such as the acrylic resin, is used as the polymer component (a), the adhesive composition and the film-like adhesive may contain the crosslinking agent (f). The crosslinking agent (f) is a component for bonding and crosslinking the functional group in the polymer component (a) with another compound, and by crosslinking in this way, the initial adhesive force and cohesive force of the film-shaped adhesive can be adjusted.

Examples of the crosslinking agent (f) include an organic polyisocyanate (polyisocynate) compound, an organic polyimine compound, a metal chelate crosslinking agent (a crosslinking agent having a metal chelate structure), an aziridine crosslinking agent (a crosslinking agent having an aziridine group), and the like.

When an organic polyisocyanate compound is used as the crosslinking agent (f), a hydroxyl group-containing polymer is preferably used as the polymer component (a). When the crosslinking agent (f) has an isocyanate group and the polymer component (a) has a hydroxyl group, the crosslinked structure can be easily introduced into the film-like adhesive by the reaction of the crosslinking agent (f) with the polymer component (a).

The crosslinking agent (f) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When the crosslinking agent (f) is used, the content of the crosslinking agent (f) in the adhesive composition is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly preferably 0.3 to 5 parts by mass, relative to 100 parts by mass of the content of the polymer component (a). By setting the content of the crosslinking agent (f) to the lower limit or more, the effect of using the crosslinking agent (f) can be more remarkably obtained. By making the content of the crosslinking agent (f) the upper limit value or less, the excessive use of the crosslinking agent (f) can be suppressed.

Energy ray-curable resin (g)

When the adhesive composition and the film-like adhesive contain the energy ray-curable resin (g), the film-like adhesive can be changed in properties by irradiation with an energy ray.

The energy ray-curable resin (g) is a resin obtained by polymerizing (curing) an energy ray-curable compound.

Examples of the energy ray-curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth) acryloyl group are preferable.

The energy ray-curable resin (g) contained in the adhesive composition may be one kind only, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When the energy ray-curable resin (g) is used, the content of the energy ray-curable resin (g) in the adhesive composition is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass, based on the total mass of the adhesive composition.

[ photopolymerization initiator (h) ]

When the adhesive composition and the film-like adhesive contain the energy ray-curable resin (g), the photopolymerization initiator (h) may be contained in order to efficiently advance the polymerization reaction of the energy ray-curable resin (g).

Examples of the photopolymerization initiator (h) in the adhesive composition include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, and benzoin dimethyl ketal; acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 2, 2-dimethoxy-1, 2-diphenylethan-1-one; acylphosphine oxide compounds such as phenylbis (2,4, 6-trimethylbenzoyl) phosphine oxide and 2,4, 6-trimethylbenzoyl diphenylphosphine oxide; sulfides such as benzyl phenyl sulfide and tetramethylthiuram monosulfide; α -ketol compounds such as 1-hydroxycyclohexyl phenyl ketone; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; thioxanthone compounds such as thioxanthone; a peroxide compound; diketone compounds such as butanedione; benzil; dibenzoyl; benzophenone; 2, 4-diethylthioxanthone; 1, 2-diphenylmethane; 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl ] propanone; quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone.

Examples of the photopolymerization initiator (h) include photosensitizers such as amines.

The photopolymerization initiator (h) contained in the adhesive composition may be one kind only, or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

When the photopolymerization initiator (h) is used, the content of the photopolymerization initiator (h) in the adhesive composition is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass, relative to 100 parts by mass of the energy ray-curable resin (g).

[ general additive (i) ]

The general-purpose additive (I) may be a known additive, may be arbitrarily selected according to the purpose, and is not particularly limited, but preferable additives include, for example, a plasticizer, an antistatic agent, an antioxidant, a colorant (dye, pigment), a gettering agent (gettering agent), and the like.

The general-purpose additive (i) contained in the adhesive composition and the film-like adhesive may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The content of the adhesive composition and the film-like adhesive is not particularly limited, and may be appropriately selected according to the purpose.

[ solvent ]

Preferably, the adhesive composition further comprises a solvent. The adhesive composition containing a solvent is excellent in workability.

The solvent is not particularly limited, but preferable examples thereof include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropane-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone.

The binder composition may contain only one kind of solvent, or two or more kinds of solvents, and in the case of two or more kinds of solvents, the combination and ratio of the solvents can be arbitrarily selected.

The solvent contained in the pressure-sensitive adhesive composition is preferably methyl ethyl ketone or the like, because the components contained in the pressure-sensitive adhesive composition can be mixed more uniformly.

The content of the solvent in the adhesive composition is not particularly limited, and may be appropriately selected depending on the kind of the component other than the solvent, for example.

Preparation method of adhesive composition

The binder composition can be obtained by blending the components for constituting the composition.

For example, the adhesive composition can be prepared by the same method as the adhesive composition described above, except that the kinds of the blending components are different.

O antistatic layer

In the solid wafer, any one of the layers may be provided as an antistatic layer.

In this case, a preferable example of the solid-state wafer is a solid-state wafer including the substrate, and the substrate is configured by laminating an adhesive layer, an intermediate layer, and a film-like adhesive in this order, and the substrate includes an antistatic layer (in this specification, it may be abbreviated as "back antistatic layer") on a surface located on a side opposite to the adhesive layer side.

Further, as a preferable example of the solid-crystal plate, there is a solid-crystal plate which includes the base material, and is configured by laminating an adhesive layer, an intermediate layer, and a film-like adhesive in this order on the base material, and the base material has an antistatic property (in this specification, the base material is sometimes abbreviated as "antistatic base material").

Further, as a preferable example of the solid wafer, there is a solid wafer which comprises the base material, and is configured by laminating an adhesive layer, an intermediate layer, and a film-like adhesive on the base material in this order, and as an antistatic layer, an antistatic layer (in this specification, sometimes abbreviated as "surface antistatic layer") is provided on a surface of the base material on the adhesive layer side.

The antistatic layers (back antistatic layer, antistatic base material and surface antistatic layer) all contain antistatic agent. Among them, a fixed wafer having a back surface antistatic layer or an antistatic base material is preferable.

The surface resistivity of the solid wafer may be 1.0 × 10¹¹Omega/□ or less. By making the surface resistivity 1.0X 10 as described below¹¹The destruction of the circuit in the semiconductor chip is suppressed below Ω/□.

The die bonding sheet of the present invention is bonded to the back surface of the semiconductor group to form a laminate composed of the die bonding sheet and the semiconductor group, and the surface of the laminate on the base material side is fixed to a dicing table (dicing table).

Next, the semiconductor wafer is divided into individual pieces in the laminated body fixed to the dicing table, and the film-like adhesive is cut to obtain a laminated body (hereinafter, abbreviated as "divided laminated body") including the substrate, the adhesive layer, the intermediate layer, the film-like adhesive after cutting, and the semiconductor wafer (i.e., semiconductor chip) after dividing in this order.

Next, the fixing of the divided laminated body to the dicing table is released, and the laminated body is conveyed to the cleaning table and fixed to the table.

Next, the laminated body fixed to the cleaning table is cleaned with water, and the chips generated and adhered during dicing in the previous step are washed and removed. The swarf originates from the semiconductor wafer, film-like adhesive. Generally, the cleaning table is rotated and cleaned.

Next, the fixation of the cleaned divided laminated body to the cleaning table is released, and the laminated body is conveyed to the drying table and fixed to the table.

Next, the laminate fixed to the drying table is dried to remove water adhering to the laminate during cleaning in the previous step. Generally, drying is performed while rotating a drying table.

Then, the fixing state of the dried divided laminated body on the drying table is released, and the laminated body is conveyed to a device for performing the next step, and the next step is performed. Then, finally, the semiconductor chip (semiconductor chip with film-like adhesive) provided with the cut film-like adhesive on the back surface is separated from the intermediate layer and picked up.

As described above, the divided laminated body is fixed to any one of the tables, and after the operation is performed, the fixed state is released and the laminated body is conveyed to a position where the next step is performed. These laminated bodies are fixed by suction on any of the tables, for example, and after the suction is released, the laminated bodies are separated from the tables and transported to the next position. In general, each of these tables has a gap portion penetrating through the table in the thickness direction, and the laminated body is sucked and fixed to the table by reducing the pressure on the side of the table opposite to the side in contact with the laminated body.

As described above, in the process of manufacturing a semiconductor chip having a film-like adhesive on the back surface using a semiconductor wafer and the die, the following operations are performed: the laminate is fixed to a table, and then the laminate is separated from the fixing surface of the table. In the solid wafer, the outermost layer of the substrate is formedThe surface resistivity of (A) is 1.0X 10¹¹At Ω/□ or less, charging at the time of separation of the laminate (in this specification, it may be referred to as "charging at the time of separation") is suppressed. As a result, the destruction of the circuit in the semiconductor chip when the separation is performed is suppressed.

As described later, in the examples, the surface resistivity of the solid wafer may be measured by using a surface resistivity meter with an applied voltage of 100V as a measurement target of the outermost layer on the substrate side in the solid wafer.

O back antistatic layer

The back antistatic layer is sheet-shaped or film-shaped and contains an antistatic agent.

The back antistatic layer may contain a resin in addition to the antistatic agent.

The back antistatic layer may be composed of one layer (single layer) or a plurality of layers of two or more layers, and when composed of a plurality of layers, these plurality of layers may be the same or different from each other, and the combination of these plurality of layers is not particularly limited.

The thickness of the back antistatic layer is preferably 200nm or less, more preferably 180nm or less, and may be, for example, 100nm or less. In the back surface antistatic layer having a thickness of 200nm or less, since the amount of the antistatic agent to be used can be reduced while maintaining sufficient antistatic ability, the cost of a fixed wafer provided with such a back surface antistatic layer can be reduced. Further, when the thickness of the back surface antistatic layer is 100nm or less, in addition to the above-described effects, an effect of being able to suppress variation in characteristics of the solid wafer to a minimum due to the back surface antistatic layer can be obtained. Examples of the characteristic include expandability.

Here, the "thickness of the back surface antistatic layer" refers to the thickness of the entire back surface antistatic layer, and for example, the thickness of the back surface antistatic layer composed of a plurality of layers refers to the total thickness of all the layers constituting the back surface antistatic layer.

The thickness of the back antistatic layer is preferably 10nm or more, and may be, for example, any of 20nm or more, 30nm or more, 40nm or more, and 65nm or more. The back antistatic layer with the thickness more than the lower limit value is easier to form, and the structure is more stable.

The thickness of the back antistatic layer can be appropriately adjusted within a range set by arbitrarily combining the above preferable lower limit value and upper limit value. For example, in one embodiment, the thickness of the back antistatic layer is preferably 10 to 200nm, and may be, for example, any one of 20 to 200nm, 30 to 200nm, 40 to 180nm, and 65 to 100 nm. However, this is only one example of the thickness of the back side antistatic layer.

The back antistatic layer may be transparent or opaque, and may be colored according to the purpose.

For example, when the film-like adhesive has energy ray curability, it is preferable that the back antistatic layer transmits energy rays.

For example, in order to optically inspect the film-like adhesive in the fixed wafer through the back surface antistatic layer, the back surface antistatic layer is preferably transparent.

Antistatic composition (VI-1)

The back antistatic layer can be formed using the antistatic composition (VI-1) containing the antistatic agent. For example, the antistatic composition (VI-1) can be applied to the surface of an object to be provided with a back antistatic layer and dried as necessary, thereby forming a back antistatic layer on the object portion. The content ratio of the components that do not vaporize at ordinary temperature in the antistatic composition (VI-1) to each other is generally the same as the content ratio of the components to each other in the back antistatic layer.

A more specific method for forming the back antistatic layer will be described in detail later together with the method for forming the other layers.

The antistatic composition (VI-1) may be applied by a known method, and may be applied by the same method as that for the above adhesive composition.

When the back antistatic layer is provided on the substrate, for example, the back antistatic layer may be laminated on the substrate by coating the antistatic composition (VI-1) on the substrate and drying it as necessary. In addition, when a back antistatic layer is provided on a substrate, for example, the back antistatic layer can be laminated on the substrate by coating the antistatic composition (VI-1) on a release film and drying it as necessary to form a back antistatic layer on the release film and attaching the exposed surface of the back antistatic layer to one surface of the substrate. The release film in this case may be removed at any time during the production process or the use process of the die bond.

The drying conditions of the antistatic composition (VI-1) are not particularly limited, but when the antistatic composition (VI-1) contains a solvent described later, it is preferably dried by heating. The antistatic composition (VI-1) containing a solvent is preferably dried at 40 to 130 ℃ for 10 seconds to 5 minutes, for example.

The antistatic composition (VI-1) may contain the resin in addition to the antistatic agent.

[ antistatic agent ]

The antistatic agent may be a known antistatic agent such as a conductive compound, and is not particularly limited. The antistatic agent may be, for example, any of a low molecular compound and a high molecular compound (in other words, an oligomer or a polymer).

Examples of the low-molecular-weight compound in the antistatic agent include various ionic liquids.

Examples of the ionic liquid include known ionic liquids such as a pyrimidinium salt, a pyridinium salt, a piperidinium salt, a pyrrolidinium salt, an imidazolium salt, a morpholinium salt, a sulfonium salt, a phosphonium salt, and an ammonium salt.

Examples of the polymer compound in the antistatic agent include poly (3, 4-ethylenedioxythiophene)/poly (styrenesulfonic acid) (in this specification, sometimes referred to as "PEDOT/PSS"), polypyrrole, carbon nanotubes, and the like. The polyazoles are oligomers or polymers having a plurality of (a plurality of) pyrrole backbones.

The antistatic agent contained in the antistatic composition (VI-1) may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

In the antistatic composition (VI-1), the proportion of the content of the antistatic agent to the total content of all the components except the solvent (i.e., the proportion of the content of the antistatic agent in the back antistatic layer to the total mass of the back antistatic layer) may be, for example, any one of 0.1 to 30 mass% and 0.5 to 15 mass%. When the ratio is not less than the lower limit, the effect of suppressing peeling electrification of the die increases, and as a result, the effect of suppressing mixing of foreign matter between the film-like adhesive and the semiconductor wafer increases. By making the ratio below the upper limit value, the strength of the back antistatic layer is further increased.

[ resin ]

The resin contained in the antistatic composition (VI-1) and the back antistatic layer may be either curable or non-curable, and in the case of being curable, may be either energy ray-curable or thermosetting.

Examples of the preferable resin include resins that function as binder resins.

More specifically, the resin includes, for example, an acrylic resin, and preferably an energy ray-curable acrylic resin.

Examples of the acrylic resin in the antistatic composition (VI-1) and the back antistatic layer include the same acrylic resins as those in the adhesive layer. Examples of the energy ray-curable acrylic resin in the antistatic composition (VI-1) and the back antistatic layer include the same acrylic resins as the adhesive resin (I-2a) in the adhesive layer.

The resin contained in the antistatic composition (VI-1) and the back antistatic layer may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

In the antistatic composition (VI-1), the proportion of the content of the resin with respect to the total content of all the components except the solvent (i.e., the proportion of the content of the resin in the back antistatic layer with respect to the total mass of the back antistatic layer) may be, for example, any one of 30 to 99.9 mass%, 35 to 98 mass%, 60to 98 mass%, and 85 to 98 mass%. By making the ratio more than the lower limit value, the strength of the back antistatic layer is further improved. By setting the ratio to the upper limit value or less, the content of the antistatic agent in the antistatic layer can be further increased.

[ energy ray-curable compound and photopolymerization initiator ]

When the antistatic composition (VI-1) contains the resin curable with energy ray, an energy ray-curable compound may be further contained.

Further, when the antistatic composition (VI-1) contains the resin curable with energy rays, a photopolymerization initiator may be contained in order to efficiently advance the polymerization reaction of the resin.

Examples of the energy ray-curable compound and the photopolymerization initiator contained in the antistatic composition (VI-1) include the same energy ray-curable compound and photopolymerization initiator as those contained in the adhesive composition (I-1).

The energy ray-curable compound and the photopolymerization initiator contained in the antistatic composition (VI-1) may be each one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The content of the energy ray-curable compound and the photopolymerization initiator in the antistatic composition (VI-1) are not particularly limited, and may be appropriately selected depending on the kind of the resin, the energy ray-curable compound, or the photopolymerization initiator.

[ other additives and solvents ]

The antistatic composition (VI-1) may further contain other additives not belonging to any of the above-mentioned components within a range not impairing the effects of the present invention.

Further, the antistatic composition (VI-1) may also contain a solvent for the same purpose as the above adhesive composition (I-1).

The other additives and solvents contained in the antistatic composition (VI-1) may be the same additives and solvents as those contained in the adhesive composition (I-1) (except for the antistatic agent). Further, as the other additives contained in the antistatic composition (VI-1), in addition to the above-mentioned components, an emulsifier can be mentioned. Further, as the solvent contained in the antistatic composition (VI-1), other alcohols such as ethanol; and alkoxyalcohols such as 2-methoxyethanol (ethylene glycol monomethyl ether), 2-ethoxyethanol (ethylene glycol monoethyl ether), and 1-methoxy-2-propanol (propylene glycol monomethyl ether).

The other additives and solvents contained in the antistatic composition (VI-1) may be one or more, and when two or more are used, the combination and ratio thereof may be arbitrarily selected.

The contents of other additives and solvents in the antistatic composition (VI-1) are not particularly limited and may be appropriately selected depending on the kind thereof.

Preparation of antistatic composition (VI-1)

The antistatic composition (VI-1) can be obtained by blending the respective components for constituting the antistatic composition (VI-1), that is, by blending the antistatic agent with components other than the antistatic agent, etc., as required.

The antistatic composition (VI-1) can be prepared by the same method as the above adhesive composition except that the blending components are different.

O antistatic base material

The antistatic base material is in a sheet shape or a film shape, has antistatic property, and further has the same function as the base material.

In the above-described solid-state wafer, the antistatic base material has the same function as the above-described laminate of the base material and the back antistatic layer, and may be disposed instead of the laminate.

The antistatic base material contains an antistatic agent and a resin, and is the same as the base material described above, for example, except that the antistatic agent is further contained.

The antistatic base material may be composed of one layer (single layer) or a plurality of layers of two or more layers, and when composed of a plurality of layers, these plurality of layers may be the same as or different from each other, and the combination of these plurality of layers is not particularly limited.

The thickness of the antistatic substrate may be, for example, the same as that of the substrate explained above. By setting the thickness of the antistatic base material to the above range, the flexibility of the die and the adhesiveness to the semiconductor wafer or the semiconductor chip can be further improved.

Here, the "thickness of the antistatic base material" refers to the thickness of the entire antistatic base material, and for example, the thickness of the antistatic base material composed of a plurality of layers refers to the total thickness of all the layers constituting the antistatic base material.

The antistatic base material may be transparent or opaque, and may be colored according to the purpose.

For example, in order to optically inspect the film-like adhesive in the fixed wafer through the antistatic base material, the antistatic base material is preferably transparent.

In order to improve the adhesiveness between the antistatic base material and a layer (for example, an adhesive layer, an intermediate layer, or a film-like adhesive) provided thereon, the surface of the antistatic base material may be subjected to unevenness treatment by sandblasting treatment, solvent treatment, or the like; corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone/ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, and other oxidation treatments. In addition, the surface of the antistatic base material may be subjected to primer treatment.

Antistatic composition (VI-2)

The antistatic base material can be produced, for example, by molding the antistatic composition (VI-2) containing the antistatic agent and the resin. The content ratio of the components which do not vaporize at ordinary temperature in the antistatic composition (VI-2) to each other is generally the same as the content ratio of the components to each other in the antistatic base material.

The antistatic composition (VI-2) can be molded by a known method, and for example, in the production of the substrate, the same method as in the molding of the resin composition can be used.

[ antistatic agent ]

Examples of the antistatic agent contained in the antistatic composition (VI-2) include the same antistatic agents as those contained in the back antistatic layer.

The antistatic agent contained in the antistatic composition (VI-2) may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

In the antistatic composition (VI-2) and the antistatic base material, the content of the antistatic agent is preferably 7.5% by mass or more, more preferably 8.5% by mass or more, based on the total content of the antistatic agent and the resin. When the ratio is not less than the lower limit, the effect of suppressing peeling electrification of the die increases, and as a result, the effect of suppressing mixing of foreign matter between the film-like adhesive and the semiconductor wafer increases.

In the antistatic composition (VI-2) and the antistatic base material, the upper limit of the ratio of the content of the antistatic agent to the total content of the antistatic agent and the resin is not particularly limited. For example, the ratio is preferably 20% by mass or less in terms of better compatibility of the antistatic agent.

The content ratio of the antistatic agent can be appropriately adjusted within a range set by arbitrarily combining the preferable lower limit value and the preferable upper limit value. For example, in one embodiment, the proportion is preferably 7.5 to 20% by mass, more preferably 8.5 to 20% by mass. However, this is only one example of the ratio.

[ resin ]

Examples of the resin contained in the antistatic composition (VI-2) and the antistatic base material include the same resins as those contained in the base material.

The resin contained in the antistatic composition (VI-2) and the antistatic base material may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

In the antistatic composition (VI-2), the proportion of the content of the resin with respect to the total content of all the components except the solvent (i.e., the proportion of the content of the resin in the antistatic base material with respect to the total mass of the antistatic base material) is preferably 30 to 99.9 mass%, more preferably 35 to 98 mass%, further preferably 60to 98 mass%, and particularly preferably 85 to 98 mass%. By setting the ratio to the lower limit value or more, the strength of the antistatic base material is further improved. By setting the ratio to the upper limit or less, the content of the antistatic agent in the antistatic base material can be further increased.

[ photopolymerization initiator ]

When the antistatic composition (VI-2) contains the resin curable with energy rays, a photopolymerization initiator may be contained in order to efficiently advance the polymerization reaction of the resin.

Examples of the photopolymerization initiator contained in the antistatic composition (VI-2) include the same photopolymerization initiators as those contained in the adhesive composition (I-1).

The photopolymerization initiator contained in the antistatic composition (VI-2) may be one kind or two or more kinds, and when two or more kinds are contained, the combination and ratio thereof may be arbitrarily selected.

The content of the photopolymerization initiator in the antistatic composition (VI-2) is not particularly limited, and may be appropriately selected according to the kind of the resin or the photopolymerization initiator.

[ additives, solvents ]

The antistatic composition (VI-2) may contain, in addition to the antistatic agent, the resin and the photopolymerization initiator, various known additives such as a filler, a colorant, an antioxidant, an organic lubricant, a catalyst, and a softener (plasticizer), which are not included in the antistatic agent, the resin and the photopolymerization initiator.

Examples of the additive contained in the antistatic composition (VI-2) include the same additives as those contained in the adhesive composition (I-1) (except for the antistatic agent).

In addition, in order to improve the flowability of the antistatic composition (VI-2), the antistatic composition (VI-2) may also contain a solvent.

Examples of the solvent contained in the antistatic composition (VI-2) include the same solvents as those contained in the adhesive composition (I-1).

The antistatic agent and the resin contained in the antistatic composition (VI-2) may be either only one type or two or more types, and when two or more types are used, the combination and ratio thereof may be arbitrarily selected.

The contents of the additive and the solvent in the antistatic composition (VI-2) are not particularly limited, and may be appropriately selected depending on the kind thereof.

Process for preparing antistatic composition (VI-2)

The antistatic composition (VI-2) can be obtained by blending the respective components for constituting the antistatic composition (VI-2), that is, by blending the antistatic agent, the resin, and, if necessary, components other than the antistatic agent and the resin, and the like.

The antistatic composition (VI-2) can be prepared by the same method as the above adhesive composition except that the blending components are different.

O surface antistatic layer

Although the arrangement position of the surface antistatic layer in the solid wafer is different from that of the back antistatic layer, the structure of the surface antistatic layer is the same as that of the back antistatic layer. For example, a surface antistatic layer can be formed using the antistatic composition (VI-1) by the same method as that for forming the back antistatic layer described above. Therefore, detailed description of the surface antistatic layer is omitted.

When the chip-on-chip has both the surface antistatic layer and the back antistatic layer, these surface antistatic layer and back antistatic layer may be the same or different.

One embodiment of the above-mentioned solid-wafer is, for example, a solid-wafer comprising a substrate and, laminated on the substrate in this order, an adhesive layer, an intermediate layer and a film-like adhesive,

[ tensile elastic modulus of the intermediate layer at 0 ℃]/[ tensile modulus of elasticity of the substrate at 0 ℃]Is 0.5 or less, the base material is in the antistatic layer is provided on one side or both sides of the base material, or the base material is provided with antistatic property, the base material sideThe surface resistivity of the outermost layer of (2) is 1.0X 10¹¹Omega/□ or less.

[ tensile elastic modulus of the intermediate layer at 0 ℃]/[ tensile modulus of elasticity of the substrate at 0 ℃]A value of 0.5 or less, the base material having an antistatic layer on a surface thereof located on a side opposite to the adhesive layer side, the surface resistivity of the outermost layer of the base material being 1.0X 10¹¹Omega/□ or less.

[ tensile elastic modulus of the intermediate layer at 0 ℃]/[ tensile modulus of elasticity of the substrate at 0 ℃]Has a value of 0.5 or less, the base material has an antistatic property, and the surface resistivity of the outermost layer of the base material is 1.0X 10¹¹Omega/□ or less.

[ tensile elastic modulus of the intermediate layer at 0 ℃]/[ tensile modulus of elasticity of the substrate at 0 ℃]The base material has an antistatic layer on the surface on the adhesive layer side, and the surface resistivity of the outermost layer of the base material is 1.0 x 10¹¹Omega/□ or less.

Manufacturing method of solid-state wafer

The solid wafer can be manufactured by stacking the layers so that the layers are in a corresponding positional relationship. The formation method of each layer is the same as that described above.

The die bond sheet can be manufactured, for example, by: the substrate, the adhesive layer, the intermediate layer, and the film-like adhesive are prepared in advance, and the substrate, the adhesive layer, the intermediate layer, and the film-like adhesive are laminated in this order. At this time, the arrangement direction of the substrate and the intermediate layer is adjusted as necessary so that the MD or TD of the substrate and the intermediate layer becomes a target direction.

In addition, the wafer fixing piece can be manufactured by the following method: 2 or more kinds of intermediate laminated bodies each formed by laminating a plurality of layers constituting a solid wafer are prepared in advance, and these intermediate laminated bodies are bonded to each other. The structure of the intermediate laminate may be arbitrarily selected as appropriate. For example, a first intermediate laminate having a structure in which a substrate and an adhesive layer are laminated and a second intermediate laminate having a structure in which an intermediate layer and a film-like adhesive are laminated are prepared in advance, and the adhesive layer in the first intermediate laminate and the intermediate layer in the second intermediate laminate are bonded to each other to prepare a solid wafer. However, this manufacturing method is only an example.

When a die bond sheet is produced in a state where a release film is provided on a film-like adhesive, for example, a film-like adhesive may be produced on the release film, and the remaining layers may be laminated while maintaining this state to produce a die bond sheet; the solid wafer may be produced by laminating all of the substrate, the adhesive layer, the intermediate layer, and the film-like adhesive, and then laminating a release film on the film-like adhesive. The release film may be removed at a necessary stage before the wafer is used.

A die bond sheet including other layers than the substrate, the adhesive layer, the intermediate layer, the film-like adhesive, and the release film can be manufactured by additionally forming the other layers at an appropriate timing and laminating them in the above-described manufacturing method.

Method of using a fixed wafer (method of manufacturing semiconductor chip with film adhesive)

In the manufacturing process of a semiconductor device, the solid wafer may be used in manufacturing a semiconductor chip with a film-like adhesive.

The method of using the fixed wafer (method of manufacturing semiconductor chips with a film-like adhesive) will be described in detail below with reference to the drawings.

Fig. 3 is a sectional view schematically illustrating a method for manufacturing a semiconductor chip to be used as a solid wafer. Fig. 4 is a sectional view for schematically illustrating a method of using the solid wafer. Here, a method of using the fixed wafer will be described by taking the fixed wafer 101 shown in fig. 1 as an example.

First, before using the die 101, as shown in fig. 3A, a semiconductor wafer 9 'is prepared, and a back-grinding tape (surface protection tape) 8 is attached to the circuit forming surface 9 a'.

In FIG. 3, reference numeral W_9’Indicating the width of the semiconductor wafer 9'.

Next, as shown in fig. 3B, a laser beam (not shown) is irradiated so as to be focused on a focal point set in the semiconductor wafer 9 ', thereby forming a modified layer 90 ' in the semiconductor wafer 9 '.

Preferably, the laser light is irradiated from the back surface 9b ' side of the semiconductor wafer 9 ' toward the semiconductor wafer 9 '.

Next, the back surface 9b 'of the semiconductor wafer 9' is polished by a polishing machine (not shown). Thus, the thickness of the semiconductor wafer 9 'is adjusted to a target value, and the semiconductor wafer 9' is divided at the formation portion of the modified layer 90 'by using the force applied to the semiconductor wafer 9' at the time of polishing, thereby forming a plurality of semiconductor chips 9 as shown in fig. 3C.

In fig. 3, reference numeral 9a denotes a circuit formation surface of the semiconductor chip 9, and corresponds to the circuit formation surface 9a 'of the semiconductor wafer 9'. Reference numeral 9b denotes the back surface of the semiconductor chip 9, and corresponds to the ground back surface 9b 'of the semiconductor wafer 9'.

In conclusion, the semiconductor chip 9 to be used as the fixed wafer 101 can be obtained. More specifically, in this step, the semiconductor chip group 901 in which the plurality of semiconductor chips 9 are aligned and fixed on the back-grinding tape 8 can be obtained.

When the semiconductor chip group 901 is viewed from above the semiconductor chip group 901 downward, a planar shape formed by connecting outermost portions of the semiconductor chip group 901 (in this specification, such a planar shape may be simply referred to as a "planar shape of the semiconductor chip group") is completely the same as a planar shape when the semiconductor wafer 9 'is viewed from above in the same manner, or the planar shapes are slightly different from each other so that the planar shape of the semiconductor chip group 901 is substantially the same as the planar shape of the semiconductor wafer 9'.

Therefore, as shown in fig. 3C, the width of the planar shape of the semiconductor chip group 901 can be regarded as the width W of the semiconductor wafer 9_9’The same is true. Moreover, the maximum value of the width of the planar shape of the semiconductor chip group 901 can be regarded as the width W of the semiconductor wafer 9_9’The maximum values of (a) are the same.

Although the semiconductor chips 9 are formed from the semiconductor wafer 9 'according to the purpose, a partial region of the semiconductor wafer 9' may not be divided into the semiconductor chips 9 depending on the conditions for polishing the back surface 9b 'of the semiconductor wafer 9'.

Next, using the semiconductor chip 9 (semiconductor chip group 901) obtained above, a semiconductor chip with a film-like adhesive is manufactured.

First, as shown in fig. 4A, while one fixed wafer 101 from which the release film 15 is removed is heated, the film-like adhesive 14 is applied to the back surfaces 9b of all the semiconductor chips 9 in the semiconductor chip group 901.

In this step, by using the die bonding sheet 101, the die bonding sheet 101 can be stably attached to the semiconductor chip 9 by the film-like adhesive 14 while being heated.

Width W of intermediate layer 13 in fixed wafer 101₁₃Maximum value of (d) and width W of film-like adhesive 14₁₄Is equal to the width W of the semiconductor wafer 9_9’(in other words, the width of the semiconductor chip group 901) is the same or the error is slight to almost the same although different.

More specifically, with respect to W₁₃Maximum value of (1) and W₁₄Maximum value of (1), W_9’The maximum value of (A) is preferably 0.88 to 1.12 times, more preferably 0.9 to 1.1 times, and particularly preferably 0.92 to 1.08 times. Namely, [ W ]_9’Is the most important ofHigh value]/[W₁₃Maximum value of]A value of and [ W_9’Maximum value of]/[W₁₄Maximum value of]The values of (A) are preferably 0.88 to 1.12, more preferably 0.9 to 1.1, and particularly preferably 0.92 to 1.08.

W₁₃Maximum value and width W of_9’Difference between maximum values of ([ W ]₁₃Maximum value of]- [ width W)_9’Maximum value of]) Preferably 0to 10mm, W₁₄Maximum value of (1) and W_9’Difference between maximum values of ([ W ]₁₄Maximum value of]- [ width W)_9’Maximum value of]) Preferably 0to 10 mm.

The heating temperature when bonding the solid wafer 101 is not particularly limited, but is preferably 40 to 70 ℃ from the viewpoint of further improving the heating bonding stability of the solid wafer 101.

Next, the back-grinding tape 8 is removed from the semiconductor chip group in the fixed state. Then, as shown in fig. 4B, the edge-cooled solid wafer 101 is stretched in a direction parallel to the surface thereof (for example, the first surface 12a of the adhesive layer 12), thereby spreading. Here, with arrow E₁Showing the direction of expansion of the solid wafer 101. By spreading in this manner, the film-like adhesive 14 can be cut along the outer periphery of the semiconductor chip 9.

According to this step, a plurality of semiconductor chip groups 910 with a film-like adhesive, in which the semiconductor chips 914 with a film-like adhesive are aligned and fixed on the intermediate layer 13, can be obtained, the semiconductor chips 914 with a film-like adhesive including the semiconductor chips 9 and the cut film-like adhesive 140 provided on the rear surfaces 9b of the semiconductor chips 9.

As described above, when a partial region of the semiconductor wafer 9 'is not divided into the semiconductor chips 9 at the time of dividing the semiconductor wafer 9', the partial region can be divided into the semiconductor chips by performing the present step.

The temperature of the solid wafer 101 is preferably set to-5 to 5 ℃. By thus cooling and spreading the fixed wafer 101, the film-like adhesive 14 can be cut more easily and with high accuracy.

The expansion of the fixed wafer 101 can be performed by a known method. For example, after the region near the peripheral edge portion of the first surface 12a of the adhesive agent layer 12 of the solid wafer 101 where the intermediate layer 13 and the film-like adhesive 14 are not laminated is fixed to a jig such as a ring frame, the entire region of the solid wafer 101 where the intermediate layer 13 and the film-like adhesive 14 are laminated is pushed up from the substrate 11 side in the direction from the substrate 11 toward the adhesive agent layer 12, whereby the solid wafer 101 is spread.

In fig. 4B, although the non-laminated region where the intermediate layer 13 and the film-like adhesive 14 are not laminated in the first surface 12a of the adhesive agent layer 12 is almost parallel to the first surface 13a of the intermediate layer 13, the non-laminated region includes the inclined surface whose height gradually decreases toward the outer periphery of the adhesive agent layer 12 in the direction opposite to the push-up direction in the state of being spread by the push-up of the fixed wafer 101 as described above.

In this step, the width W of the intermediate layer 13₁₃Maximum value of (d) and width W of the semiconductor wafer 9_9’When the difference between the maximum values of (A) and (B) is 0to 10mm, a high effect of suppressing scattering of the film-like adhesive 140 after cutting other than the purpose can be obtained. Here, "scattering of the film-like adhesive 140 after cutting out of the purpose" means that a film-like adhesive originating from a peripheral edge portion (in fig. 4, illustration of such a peripheral edge portion is omitted) of the film-like adhesive 14 that is not originally attached to the semiconductor wafer 9' among the film-like adhesive 140 after cutting off scatters and adheres to the circuit-formation-surface 9a of the semiconductor chip 9.

In this step, since the notch width can be sufficiently widened with respect to the elongation of the base material by setting the tensile elastic modulus ratio Ei '/Eb' to 0.5 or less in the fixed wafer 101, the film-like adhesive can be stably cut (divided) along the outer periphery of the semiconductor chip when the fixed wafer is expanded.

Next, as shown in fig. 4C, the laminated sheet derived from the base material 11, the adhesive agent layer 12, and the intermediate layer 13 of the fixed wafer 101 is spread in a direction parallel to the first surface 12a of the adhesive agent layer 12, and the peripheral edge portion of the semiconductor chip 914 (semiconductor chip group 910 with a film-like adhesive agent) on which the film-like adhesive agent is not mounted is heated so as to maintain this state.

Here, with arrow E₂Indicating the direction of propagation of the laminate. The extension direction of the laminated sheet is the same as that of the above-described fixed wafer 101.

Here, a peripheral edge portion of the laminate sheet to be heated is indicated by an arrow H. The peripheral portion to be heated is included in the non-lamination region.

In the present embodiment, it is preferable that: after the spread of the solid-crystal sheet 101 at the time of cutting the film-like adhesive 14 is released, the laminated sheet is spread in this step.

In this step, the laminated sheet can be spread by the same method as that for the above-described fixed wafer 101. For example, after a region in the vicinity of the peripheral edge portion of the first surface 12a of the adhesive layer 12 in the laminated sheet where the intermediate layer 13 is not laminated is fixed to a jig, the entire region of the laminated sheet where the intermediate layer 13 is laminated is pushed up from the substrate 11 side in the direction from the substrate 11 toward the adhesive layer 12, thereby spreading the laminated sheet.

In fig. 4C, although the non-laminated region (region including the peripheral edge portion indicated by the arrow H) in which the intermediate layer 13 and the film-like adhesive 14 are not laminated in the first surface 12a of the adhesive agent layer 12 is almost parallel to the first surface 13a of the intermediate layer 13, the non-laminated region includes the inclined surface whose height gradually decreases as it approaches the outer periphery of the adhesive agent layer 12 in the direction opposite to the push-up direction in a state of spreading by the push-up of the laminated sheet as described above.

In this step, by using the fixing wafer 101, the peripheral edge portion can be contracted, and the distance between the adjacent semiconductor chips 9, that is, the notch width can be sufficiently widened in the laminated sheet and the notch width can be maintained with high uniformity. For example, in the present embodiment, the slit width after the present step may be 10 μm or more, or all the slit widths may be 10 μm or more. Further, the difference between the maximum value and the minimum value among the widths of the plurality of notches may be 100 μm or less.

Thus, by making the slit width wide enough and maintaining the slit width with high uniformity, as described later, the semiconductor chip with the film adhesive can be easily picked up.

The temperature of the semiconductor chip group 910 with the film-like adhesive is preferably set to a low temperature, for example, -15 to 0 ℃. By expanding the semiconductor chip group 910 with the film-like adhesive at such a temperature, the effect of making the kerf width sufficiently wide and being able to maintain the kerf width with higher uniformity is further improved.

After the film-like adhesive 14 is cut, the semiconductor chip 914 with the film-like adhesive is separated from the intermediate layer 13 in the laminated sheet, and is picked up. At this time, as described above, by making the slit width sufficiently wide and having high uniformity, the semiconductor chip 914 with the film adhesive can be easily picked up. The semiconductor chip 914 with the film-like adhesive can be picked up by a known method.

Here, the method of using the fixed wafer is described by taking the fixed wafer 101 shown in fig. 1 as an example, but other fixed wafers of the present embodiment may be used similarly. In this case, if necessary, other steps may be added as appropriate based on the difference in structure between the solid wafer and the solid wafer 101.

A preferred embodiment of the method for manufacturing a semiconductor chip with a film-like adhesive includes, for example, a method for manufacturing a semiconductor chip with a film-like adhesive, the semiconductor chip with a film-like adhesive including a semiconductor chip and a film-like adhesive provided on a back surface of the semiconductor chip, the method including the steps of: a step of irradiating a laser beam so as to focus on a focal point set inside a semiconductor wafer, thereby forming a modified layer inside the semiconductor wafer; a step of obtaining a semiconductor chip group in which a plurality of semiconductor chips are aligned by grinding the back surface of the semiconductor wafer on which the modified layer is formed and dividing the semiconductor wafer at a portion where the modified layer is formed by a force applied to the semiconductor wafer during grinding; heating the fixed wafer while adhering the film-like adhesive to the back surfaces of all the semiconductor chips in the semiconductor chip group; a step of stretching the fixed wafer in a direction parallel to the surface thereof while cooling the fixed wafer bonded to the semiconductor chip group, thereby cutting the film-like adhesive along the outer periphery of the semiconductor chips to obtain a plurality of semiconductor chip groups with the film-like adhesive, the semiconductor chip groups being arranged in alignment with each other; a step of spreading a laminated sheet derived from the base material, the adhesive agent layer, and the intermediate layer of the solid wafer after obtaining the semiconductor chip with the film-like adhesive in a direction parallel to the surface of the adhesive agent layer, and further heating the peripheral edge portion of the semiconductor chip without the film-like adhesive placed thereon in the laminated sheet so as to maintain the state; and a step of separating the semiconductor chip with the film-like adhesive from the intermediate layer in the laminated sheet after heating the peripheral edge portion, thereby picking up the semiconductor chip with the film-like adhesive, wherein a difference between a maximum value of the width of the intermediate layer and a maximum value of the width of the semiconductor wafer is 0to 10 mm.

Examples

The present invention will be described in more detail below with reference to specific examples. However, the present invention is not limited to the examples shown below.

Raw Material for preparation of adhesive composition

The raw materials used to prepare the adhesive composition are shown below.

[ Polymer component (a) ]

(a) -1: an acrylic resin (weight average molecular weight 800000, glass transition temperature 9 ℃) obtained by copolymerizing methyl acrylate (95 parts by mass) and 2-hydroxyethyl acrylate (5 parts by mass).

[ epoxy resin (b1) ]

(b1) -1: cresol novolak type epoxy resin having an acryloyl group added thereto ("CNA 147" manufactured by Nippon Kayaku Co., Ltd., number average molecular weight of 518g/eq, number average molecular weight of 2100, unsaturated group content equivalent to epoxy group)

[ Heat-curing agent (b2) ]

(b2) -1: aralkyl type phenol resin ("Milex XLC-4L" manufactured by Mitsui Chemicals, Inc., number average molecular weight 1100, softening point 63 ℃ C.)

[ Filler (d) ]

(d) -1: spherical silica (YA 050C-MJE manufactured by Admatech corporation, average particle diameter 50nm, methacryl silane-treated product)

[ coupling agent (e) ]

(e) -1: silane coupling agent, 3-glycidyloxypropylmethyldiethoxysilane ("KBE-402" manufactured by shin-Ethersilicon Co., Ltd.)

[ crosslinking agent (f) ]

(f) -1: toluene diisocyanate crosslinking agent ("CORONATE L" manufactured by TOSOH CORPORATION)

[ antistatic composition (as) ]

(as) -1: polypyrrole was emulsified with a reactive emulsifier and dissolved in an organic solvent to obtain a polypyrrole solution.

(as) -2: "UVH 515" manufactured by Idemitsu Kosan co., ltd "

[ example 1]

Production of solid wafer

< production of substrate >

Low density polyethylene ("sumikanene L705" manufactured by Sumitomo Chemical co., ltd.) was melted using an extruder, the melt was extruded by a T-die method, and the extrudate was biaxially stretched using a chill roll, thereby obtaining a base material (thickness 110 μm) made of LDPE.

< production of intermediate layer >

An ethylene-vinyl acetate copolymer ("Ultrathene 636" manufactured by TOSOH CORPORATION) was melted by using an extruder, the melt was extruded by a T-die method, and the extrudate was biaxially stretched by using a chill roll and further partially cut, thereby obtaining an EVA interlayer (thickness 80 μm) having a circular planar shape (diameter 305 mm).

< preparation of adhesive layer >

A non-energy ray-curable adhesive composition containing an acrylic resin (ORIBAIN BPS 6367X manufactured by TOYOCHEM co., ltd.) (100 parts by mass) and a crosslinking agent (byochem co., ltd. "BXX 5640") as an adhesive resin (I-1a) (1 part by mass) was prepared.

Next, using a release film obtained by subjecting one surface of the polyethylene terephthalate film to a release treatment by a silicone treatment, the obtained adhesive composition was applied to the release-treated surface of the release film, and heated and dried at 100 ℃ for 2 minutes, thereby producing a non-energy ray-curable adhesive layer (thickness 10 μm).

< production of film-shaped adhesive >

A thermosetting adhesive composition containing polymer component (a) -1(100 parts by mass), epoxy resin (b1) -1(10 parts by mass), thermosetting agent (b2) -1(1.5 parts by mass), filler (d) -1(75 parts by mass), coupling agent (e) -1(0.5 part by mass), and crosslinking agent (f) -1(0.5 part by mass) was prepared.

Next, using a release film obtained by subjecting one surface of a polyethylene terephthalate film to a release treatment by a silicone treatment, the adhesive composition obtained above was applied to the release-treated surface of the release film, and was dried by heating at 80 ℃ for 2 minutes, and further partially cut, thereby obtaining a thermosetting film-like adhesive (thickness 20 μm) having a circular planar shape (diameter 305 mm).

< manufacture of solid wafer >

The exposed surface of the obtained adhesive layer on the side opposite to the side having the release film was bonded to one surface of the obtained substrate.

The exposed surface of the obtained film-like adhesive on the side opposite to the side provided with the release film was bonded to one surface of the obtained intermediate layer. At this time, the film-like adhesive and the intermediate layer are disposed concentrically.

Next, the release film was removed from the laminate of the release film, the adhesive layer, and the substrate obtained in this manner (corresponding to the first intermediate laminate with the release film described above), and the exposed surface of the newly produced adhesive layer was bonded to the exposed surface of the intermediate layer in the laminate of the release film, the film-like adhesive, and the intermediate layer (corresponding to the second intermediate laminate with the release film described above). At this time, the arrangement direction of the substrate and the intermediate layer is adjusted so that the MD of the substrate and the MD of the intermediate layer coincide (in other words, the TD of the substrate and the TD of the intermediate layer coincide). In this way, a release film-attached die was obtained in which a substrate (thickness 110 μm), an adhesive layer (thickness 10 μm), an intermediate layer (thickness 80 μm), a film-like adhesive (thickness 20 μm), and a release film were laminated in this order in the thickness direction.

Production of semiconductor chip with film-shaped adhesive

A semiconductor wafer having a circular planar shape with a diameter of 300mm and a thickness of 775 μm was used, and a back grinding tape ("Adwill E-3100 TN" manufactured by LINTEC Corporation) was attached on the circuit forming surface of the semiconductor wafer.

Next, laser light was irradiated using a laser irradiation apparatus ("DFL 73161" manufactured by DISCO Corporation) so as to be focused on a focal point set inside the semiconductor wafer, thereby forming a modified layer inside the semiconductor wafer. In this case, the focus is set so that a plurality of semiconductor chips having a size of 8mm × 8mm can be obtained from the semiconductor wafer. The semiconductor wafer 9 is irradiated with laser light from the back surface side of the semiconductor wafer.

Then, the back surface of the semiconductor wafer was polished by a polishing machine to make the thickness of the semiconductor wafer 30 μm, and the semiconductor wafer was divided at the formation portion of the modified layer by a force applied to the semiconductor wafer at the time of polishing to form a plurality of semiconductor chips. Thus, a semiconductor chip group in which a plurality of semiconductor chips are aligned and fixed on the back grinding adhesive tape is obtained.

Next, one of the above-obtained solid wafers was heated to 60 ℃ while a film-like adhesive was applied to the back surfaces of all the semiconductor chips (semiconductor chip groups) using a tape laminator ("Adwill RAD 2500" manufactured by LINTEC Corporation). Then, a semiconductor chip group having a back-grinding tape on a circuit forming surface and a die-bonding sheet on a back surface is fixed by attaching a peripheral edge portion included in the non-lamination region in an adhesive layer of the die-bonding sheet attached to the semiconductor chip group to an annular frame.

Then, the back grinding tape is removed from the semiconductor chip group in the fixed state. Then, the film-like adhesive was cut along the outer periphery of the semiconductor chip by spreading the wafer in a direction parallel to the surface thereof while cooling the wafer in an environment of 0 ℃. At this time, the peripheral edge of the die bond sheet was fixed, and the entire region of the die bond sheet where the intermediate layer and the film-like adhesive were laminated was pushed up by a height of only 15mm from the substrate side of the die bond sheet, thereby spreading the adhesive layer.

Thus, a semiconductor chip group with a film-like adhesive is obtained, which includes a plurality of semiconductor chips with a film-like adhesive provided on the back surface thereof and a plurality of cut film-like adhesive-provided semiconductor chips, and which is aligned and fixed on the intermediate layer.

Next, after the spread of the solid-state wafer is once released, the laminated sheet formed by laminating the base material, the adhesive agent layer, and the intermediate layer is spread in a direction parallel to the first surface of the adhesive agent layer at normal temperature. Further, the peripheral edge portion of the semiconductor chip on which the adhesive tape is not mounted in the laminate sheet is heated so as to maintain the spread state. Thereby, the peripheral edge portion is contracted, and the notch width between the adjacent semiconductor chips is kept at a constant value or more in the laminated sheet.

Evaluation of substrate

< calculation of the rate of change of displacement at heating, the rate of change at cooling, and the overall rate of change >

The obtained base material was subjected to thermomechanical analysis (TMA) using a thermomechanical analyzer ("TMA 4000 SA" manufactured by Bruker AXS) according to the following procedure.

That is, first, the base material was cut into pieces of 4.5mm × 15mm, thereby producing test pieces.

Next, the test piece was set in the thermomechanical analyzer, and TMA was performed so that the temperature of the test piece was not changed with the load applied to the test piece set to 2g, thereby measuring the amount X of displacement in MD at a temperature of 23 ℃₀. The temperature rise rate was set to 20 ℃/min and the load was set to 2g, and the displacement X was measured₀The temperature of the test piece was raised to 70 ℃ and the heating was carried out before the completion of the raising of the temperatureTMA, whereby the maximum value X of the amount of displacement of the test piece in MD during the temperature rise period is measured₁. The load is set to 2g, and the displacement X is measured₁The test piece was cooled at 23 ℃ and TMA was carried out before the cooling was completed, whereby the minimum value X of the amount of displacement of MD of the test piece during the cooling period was measured₂。

Then, the above-mentioned X is used₀、X₁And X₂Based on the above equations (1), (2) and (3), the rate of change during heating, the rate of change during cooling, and the overall rate of change of the MD displacement of the test piece are calculated.

Further, in the TD of the test piece, the heating-time change rate, the cooling-time change rate, and the total change rate of the displacement amount are calculated in the same manner.

The results are shown in Table 1.

< determination of tensile elastic modulus Eb >

A test piece having a width of 15mm was cut out from the substrate obtained above.

Next, the temperature of the set position of the test piece of the testing machine was maintained at 0 ℃ in advance, and the test piece was set at the set position.

Subsequently, the test piece was stretched at a stretching speed of 200mm/min with the chuck pitch set at 100mm and the temperature maintained at 0 ℃ by using TENSILON, and the tensile elastic modulus Eb' of the MD of the test piece at 0 ℃ in the elastic deformation region was measured.

Further, in the TD of the test piece at 0 ℃, the tensile elastic modulus Eb' was also measured in the same manner.

The results are shown in Table 1.

Evaluation of intermediate layer

< determination of tensile elastic modulus Ei >

A test piece having a width of 15mm was cut out from the intermediate layer obtained above.

Next, the tensile elastic modulus Ei' of MD and TD at 0 ℃ was measured for the test piece of the intermediate layer in the same manner as for the test piece of the base material.

The results are shown in Table 1.

Calculation of tensile elastic modulus ratio Ei '/Eb')

Using the measured values of the tensile elastic modulus Eb 'and the tensile elastic modulus Ei' obtained above, the tensile elastic modulus ratio Ei '/Eb' in both directions of the MD of the substrate and the intermediate layer and the TD of the substrate and the intermediate layer was calculated.

The results are shown in Table 1.

Evaluation of solid wafer

< cuttability of film-like adhesive >

In the production of the semiconductor chip with the film-like adhesive, the obtained semiconductor chip group with the film-like adhesive was observed from above the semiconductor chip side of the semiconductor chip group using a digital microscope ("VH-Z100" manufactured by KEYENCE CORPORATION). Then, when the film-like adhesive is supposed to be normally cut by spreading of the die, the number of cutting lines that are not actually formed and the number of incomplete cutting lines among the plurality of cutting lines of the film-like adhesive extending along the MD of the intermediate layer and the plurality of cutting lines of the film-like adhesive extending along the TD of the intermediate layer that should be formed are confirmed, and the cuttability of the film-like adhesive is evaluated according to the following evaluation criteria. The results are shown in Table 1.

(evaluation criteria)

A: the total number of the cutting lines of the film-like adhesive which is not actually formed and the cutting lines of the film-like adhesive which is incompletely formed is 5 or less.

B: the total number of the cutting lines of the film-like adhesive which is not actually formed and the cutting lines of the film-like adhesive which is incompletely formed is 6 or more.

< fly inhibition of film-like adhesive >

When the above film-like adhesive was evaluated for cuttability, the semiconductor chip group with the film-like adhesive was visually observed from above the semiconductor chip side of the semiconductor chip group. Then, whether or not the cut film-like adhesive that has scattered is adhered to the circuit formation surface of the semiconductor chip is checked, and the scattering suppression property of the film-like adhesive is evaluated according to the following evaluation criteria. The results are shown in Table 1.

(evaluation criteria)

A: the number of the semiconductor chips to which the film-like adhesive was attached to the circuit-formation-face was observed to be 0.

B: the number of semiconductor chips attached to the circuit-formed surface with the film-like adhesive was observed to be 1 or more.

< notch retentivity >

In the production of the semiconductor chip with the film-like adhesive, the laminated sheet was spread at normal temperature, and after heating the peripheral edge portion of the laminated sheet, the notch retentivity was evaluated by the following method.

That is, when the film-like adhesive is normally cut by spreading of the fixing sheet, in the spread semiconductor chip group with the film-like adhesive, the plurality of cuts extending along the MD of the intermediate layer and the plurality of cuts extending along the TD of the intermediate layer are formed in a lattice shape. The MD slit width and TD slit width of the intermediate layer were measured from above the semiconductor chip side of the semiconductor chip group with a film adhesive, using a digital microscope ("VH-Z100" manufactured by KEYENCE CORPORATION) at the following total of 5 positions: of the intersection points (in other words, orthogonal points) of the slits extending in the MD of the intermediate layer and the slits extending in the TD of the intermediate layer, a central intersection point (also referred to as a "first intersection point" in this specification) corresponding to a substantially central portion of the silicon wafer before division; 2 intersection portions (also referred to as "second intersection portion" and "fourth intersection portion", respectively, in this specification) which are located closest to the outer periphery of the silicon wafer before division and in which the TD of the intermediate layer is located at the same position as the central intersection portion (first intersection portion); and 2 intersection portions (also referred to as "third intersection portion" and "fifth intersection portion", respectively, in this specification) which are positioned closest to the outer periphery of the silicon wafer before division and are positioned at the same positions as the central intersection portion (first intersection portion) in the MD of the intermediate layer. That is, the measured values of the slit width at each intersection are 1 and 2 in total in MD and TD, and the total number of the measured values of the slit width at 5 intersections is 10 in total.

Fig. 5 shows the measurement position of the slit width at this time. In fig. 5, reference numeral 7 denotes a semiconductor chip, and 79a denotes a slit extending in the MD of the intermediate layerAnd 79b, a slit extending along the TD of the intermediate layer. When the solid wafer used is the solid wafer shown in fig. 1, the first surface 13a of the intermediate layer 13 is exposed in the notch 79a and the notch 79 b. And, reference numeral W_a1、W_a2、W_a3、W_a4And W_a5Each indicates the width of a slit extending in the MD of the intermediate layer (in other words, the slit width of the TD at the intersection), and is denoted by reference numeral W_b1、W_b2、W_b3、W_b4And W_b5Both indicate the width of the cut extending along the TD of the middle layer (in other words, the width of the cut in the MD at the intersection). Determination of the incision Width W_a1And W_b1The crossing portion of (a) is the first crossing portion. Further, the width W of the notch was measured_a2And W_b2The crossing part of (2) is the second crossing part, and the width W of the incision is measured_a4And W_b4The crossing portion of (a) is the fourth crossing portion. Further, the width W of the notch was measured_a3And W_b3The intersection of (A) and (B) is the third intersection, and the incision width W is measured_a5And W_b5The crossing portion of (a) is the fifth crossing portion.

Fig. 5 is a plan view schematically showing a semiconductor chip set with a film-like adhesive for explaining the measurement position of the slit width, and the slit width is constant at any place. Even in the same semiconductor chip group with the film adhesive, the slit width may vary depending on the position of the slit, and in each of the examples and comparative examples, the slit width may vary even in the same position of the slit in the semiconductor chip group with the film adhesive.

Then, based on the measured values of the 10 notch widths, the notch retentivity was evaluated in accordance with the following evaluation criteria. The results are shown in Table 1.

(evaluation criteria)

A: all the measured values of the slit width were 10 μm or more, and the difference between the maximum value and the minimum value of the measured values was 100 μm or less.

B: the measured value of the width of more than 1 notch is less than 10 μm; or the measured values of the slit widths are all 10 μm or more, and the difference between the maximum value and the minimum value of the measured values exceeds 100 μm.

< surface resistivity >

The film-like adhesive in the solid wafer was thermally cured at 130 ℃ for 2 hours.

Next, using a surface Resistivity meter ("R12704 Resistivity chamber" manufactured by ADVANTEST CORPORATION), the surface Resistivity was measured on the surface of the base material located on the opposite side to the adhesive agent layer side with the applied voltage set to 100V. The results are shown in Table 1 under the heading "surface resistivity (. OMEGA/□)".

< semiconductor chip with film adhesive, and lifting between intermediate layers >

The group of semiconductor chips with a film-like adhesive obtained after the process of a full-automatic die bonder ("DDS 2300" manufactured by DISCO Corporation) was observed with the naked eye from the substrate side (non-semiconductor chip side) to confirm whether or not the semiconductor chips with the film-like adhesive floated from the intermediate layer.

(evaluation criteria)

A: the semiconductor chip with the film-like adhesive does not float

B: some of the 100 semiconductor chips with the film-like adhesive slightly floated

[ example 2]

Production of solid wafer, production of semiconductor chip with film-like adhesive, evaluation of substrate, evaluation of intermediate layer, and evaluation of solid wafer

A fixed wafer and a semiconductor chip with a film adhesive were produced in the same manner as in example 1 except that the diameter of the intermediate layer was set to 310mm instead of 305mm, and the substrate, the intermediate layer, and the fixed wafer were evaluated. The results are shown in Table 1.

[ example 3]

Production of solid wafer

< production of substrate >

Polypropylene ("Prime Polypro F-744 NP" manufactured by Prime Polymer co., ltd.) was melted using an extruder, the melt was extruded by a T-die method, and the extrudate was biaxially stretched using a chill roll, thereby obtaining a PP-made substrate (thickness 50 μm).

Production of semiconductor chip with film-shaped adhesive

A die and a semiconductor chip with a film adhesive were produced in the same manner as in example 1, except that the PP base material obtained above was used instead of the LDPE base material.

Evaluation of substrate and evaluation of die bonding

The base material and the wafer-bonded piece obtained above were evaluated by the same method as in example 1. The results are shown in Table 1.

[ example 4]

A fixed wafer and a semiconductor chip with a film adhesive were produced in the same manner as in example 1 except that the diameter of the intermediate layer was set to 320mm instead of 305mm, and the intermediate layer and the fixed wafer were evaluated. The results are shown in Table 1.

[ example 5]

Production of solid wafer

< production of substrate >

The antistatic composition (AS) -1 was applied to the surface of the substrate obtained in example 1 on the side opposite to the adhesive layer side, and dried at 100 ℃ for 2 minutes, thereby producing a substrate having a back antistatic layer (AS1) having a thickness of 75nm formed on the substrate.

A wafer-bonded sheet with a release film, which was composed of an antistatic layer, a substrate, an adhesive layer, an intermediate layer, a film-like adhesive, and a release film laminated in this order in the thickness direction thereof, was produced in the same manner AS in example 1, except that the substrate with the back antistatic layer (AS1) formed thereon was used instead of the LDPE substrate.

Production of semiconductor chip with film-shaped adhesive

Using the obtained solid wafer, a semiconductor chip with a film-like adhesive was produced in the same manner as in example 1.

Evaluation of substrate, evaluation of intermediate layer, and evaluation of solid wafer

The substrate, the intermediate layer, and the wafer were evaluated in the same manner as in example 1. The results are shown in Table 2.

[ example 6]

< production of substrate >

Using the antistatic composition (AS) -2 in place of the antistatic composition (AS) -1, a substrate having a back antistatic layer (AS2) formed to a thickness of 170nm was produced.

Using this base material, a wafer with a release film was produced in the same manner as in example 5.

Production of semiconductor chip with film-shaped adhesive

Using the obtained solid wafer, a semiconductor chip with a film-like adhesive was produced in the same manner as in example 5.

[ example 7]

Production of solid wafer

< production of antistatic base Material >

An energy ray-curable antistatic composition was obtained by blending a composition containing a urethane acrylate resin and a photopolymerization initiator and having a ratio of the content of the photopolymerization initiator to the content of the urethane acrylate resin of 3.0 mass% with a phosphonium ionic liquid (an ionic liquid composed of a phosphonium salt) as an antistatic agent and stirring the mixture. In this case, the content of the antistatic agent in the antistatic composition was 9.0 mass% based on the total content of the antistatic agent and the urethane acrylate resin.

Then, the antistatic composition obtained above was applied to a process film (a 50 μm thick product of "Lumiror T60 PET 50T-60 Toray" manufactured by TORAY INDUSTRIES, INC.) made of polyethylene terephthalate by a fountain die (fountain die) method to form a coating film having a thickness of 80 μm. Then, the substrate was cured with ultraviolet rays using an ultraviolet irradiation apparatus ("ECS-401 GX" manufactured by EYE GRAPHICS co., ltd.) and a high-pressure mercury lamp ("H04-L41" manufactured by EYE GRAPHICS co., ltd.) to obtain an antistatic base material comprising an antistatic agent and a urethane acrylate resin.

A wafer bonded with a release film was produced in the same manner as in example 1, except that the antistatic base material obtained above was used instead of the LDPE base material.

Production of semiconductor chip with film-shaped adhesive

Comparative example 1

Production of solid wafer

< production of substrate >

An ethylene-vinyl acetate copolymer ("Ultrathene 636" manufactured by TOSOH CORPORATION) was melted using an extruder, the melt was extruded by a T-die method, and the extrudate was biaxially stretched using a chill roll, thereby obtaining an EVA-made substrate (thickness 120 μm).

Production of semiconductor chip with film-shaped adhesive

A die and a semiconductor chip with a film adhesive were produced in the same manner as in example 1, except that the EVA base material obtained above was used instead of the LDPE base material.

Evaluation of substrate and evaluation of die bonding

The base material and the wafer-bonded piece obtained above were evaluated by the same method as in example 1. The results are shown in Table 2.

Comparative example 2

< production of intermediate layer >

An intermediate layer (thickness 70 μm) made of a polymer alloy of PE and EVA (hereinafter, referred to as "PE/EVA system") having a circular planar shape (diameter 305mm) was obtained by melting low-density polyethylene ("sumikanene L705", manufactured by Sumitomo Chemical co., ltd., 50 parts by mass) and an ethylene-vinyl acetate copolymer ("EVA," Ultrathene 636 ", manufactured by TOSOH CORPORATION, 20 parts by mass) using an extruder, extruding the melt by a T-die method, biaxially stretching the extrudate using a chill roll, and further cutting a part of the extrudate.

Production of semiconductor chip with film-shaped adhesive

A die and a semiconductor chip with a film adhesive were produced in the same manner as in example 1, except that the PE/EVA interlayer obtained above was used instead of the EVA interlayer.

Evaluation of intermediate layer and solid wafer

The intermediate layer and the wafer having been obtained as described above were evaluated by the same method as in example 1. The results are shown in Table 2.

[ Table 1]

[ Table 2]

From the above results, it is clear that in examples 1 to 7, both the cuttability and the notch retentivity of the film-like adhesive in the die were good.

In examples 1 to 2 and 4 to 6, Eb' was 90MPa in MD and 104MPa in TD. Furthermore, Ei' is 25MPa in MD and 33MPa in TD. As a result, Ei '/Eb' was 0.28 in MD and 0.32 in TD.

In example 3, Eb' was 65MPa in MD and 67MPa in TD. Furthermore, Ei' is 25MPa in MD and 33MPa in TD. As a result, Ei '/Eb' was 0.38 in MD and 0.49 in TD.

In example 7, Eb' was 100MPa in MD and 100MPa in TD. Furthermore, Ei' is 25MPa in MD and 33MPa in TD. As a result, Ei '/Eb' was 0.25 in MD and 0.33 in TD.

In examples 1 to 2 and 4 to 6, the rate of change in the amount of displacement of the substrate (test piece) upon heating was 0.8% in MD and 0.7% in TD. In example 7, the rate of change in the amount of displacement of the substrate (test piece) when heated was 0.8% in MD and 0.8% in TD.

In examples 1 to 2 and 4 to 6, the rate of change in the amount of displacement of the substrate (test piece) when it was cooled down was-1.9% in both MD and TD. In example 7, the rate of change in the amount of displacement of the substrate (test piece) when it was cooled was-1.8% in both MD and TD.

In examples 1 to 2 and 4 to 6, the total change rate of the displacement amount of the base material (test piece) was-1.1% in MD and-1.2% in TD. In example 7, the total change rate of the displacement amount of the base material (test piece) was-1.0% in both MD and TD.

In example 4, the difference was larger than 10mm (20 mm), and thus the scattering suppression property of the film-like adhesive was poor in example 4.

On the other hand, in examples 1 to 3 and 5 to 7, since the difference between the diameter of the intermediate layer and the diameter of the semiconductor wafer was 10mm or less (5 to 10mm), the scattering suppression property of the film-like adhesive was good.

In example 3, the rate of change in the amount of displacement of the base material (test piece) when heated was 2.9% in TD.

In example 3, the total change rate of the displacement amount of the base material (test piece) was 1.5% in TD.

On the other hand, in comparative examples 1 to 2, the film-like adhesive in the die was inferior in cuttability and notch retentivity.

In comparative example 1, Eb' was 25MPa in MD and 33MPa in TD. Furthermore, Ei' is 25MPa in MD and 33MPa in TD. As a result, Ei '/Eb' was 1.00 in both MD and TD.

In comparative example 2, Eb' was 90MPa in MD and 104MPa in TD. Furthermore, Ei' is 63MPa in MD and 55MPa in TD. As a result, Ei '/Eb' was 0.70 in MD and 0.53 in TD.

In comparative example 1, the MD shows a change rate of the amount of displacement of the substrate (test piece) in cooling at-2.8%.

In comparative example 1, the total change rate of the displacement amount of the base material (test piece) was-2.6% in MD.

In examples 5 to 7, since the base material formed with the back antistatic layer or the antistatic base material was used as the base material, the surface resistivity was 1.0X 10¹¹Omega/□ or less.

On the other hand, in examples 1 to 4, comparative examples 1 and 2, since the base material having the back surface antistatic layer formed thereon or the antistatic base material was not used as the base material, the surface resistivity was more than 1.0 × 10¹¹Ω/□。

In examples 1 to 4, comparative examples 1 and 2, which were not provided with antistatic property, foreign matter was mixed between the stage and the fixed wafer due to the influence of static electricity or the like in the process of the full automatic die bonder ("DDS 2300" manufactured by DISCO Corporation), a step difference was generated between a portion having the foreign matter and a portion having no foreign matter, a trigger was generated that the semiconductor chip with the film adhesive was peeled off from the intermediate layer, and as a result, chip lifting was locally generated, and finally chip scattering was generated.

On the other hand, in examples 5 to 7 in which antistatic property was imparted, foreign matter was not easily mixed between the stage and the fixed wafer, and chip lifting did not occur.

Industrial applicability

The invention can be used for manufacturing semiconductor devices.

Description of the reference numerals

101: fixing the wafer; 11: a substrate; 12: an adhesive layer; 13: an intermediate layer; 14: a film-like adhesive; w₁₃: the width of the intermediate layer; w₁₄: the width of the film adhesive.

Claims

1. A die bond sheet comprising a substrate, and an adhesive layer, an intermediate layer and a film-like adhesive laminated in this order on the substrate,

[ tensile elastic modulus of the intermediate layer at 0 ℃ (0 ℃)/[ tensile elastic modulus of the base material at 0 ℃) ] is 0.5 or less.

2. The solid wafer of claim 1, wherein the width of the intermediate layer is a maximum of 150 to 160mm, 200 to 210mm, or 300 to 310 mm.

3. A method for manufacturing a semiconductor chip with a film-like adhesive, the semiconductor chip with the film-like adhesive including a semiconductor chip and a film-like adhesive provided on a back surface of the semiconductor chip, the method comprising:

a step of irradiating a laser beam so as to focus on a focal point set inside a semiconductor wafer, thereby forming a modified layer inside the semiconductor wafer;

a step of obtaining a semiconductor chip group in which a plurality of semiconductor chips are aligned by grinding the back surface of the semiconductor wafer on which the modified layer is formed and dividing the semiconductor wafer at a portion where the modified layer is formed by a force applied to the semiconductor wafer during grinding;

a step of attaching the film-like adhesive to the back surfaces of all the semiconductor chips in the semiconductor chip group while heating the die bond sheet according to claim 1 or 2;

a step of stretching the fixed wafer in a direction parallel to the surface thereof while cooling the fixed wafer bonded to the semiconductor chip group, thereby cutting the film-like adhesive along the outer periphery of the semiconductor chips to obtain a plurality of semiconductor chip groups with the film-like adhesive, the semiconductor chip groups being arranged in alignment with each other;

a step of spreading a laminated sheet derived from the base material, the adhesive agent layer, and the intermediate layer of the solid wafer after obtaining the semiconductor chip with the film-like adhesive in a direction parallel to the surface of the adhesive agent layer, and further heating the peripheral edge portion of the semiconductor chip without the film-like adhesive placed thereon in the laminated sheet so as to maintain the state; and

a step of separating the semiconductor chip with the film-like adhesive from the intermediate layer in the laminate sheet after heating the peripheral edge portion, thereby picking up the semiconductor chip with the film-like adhesive,

the difference between the maximum value of the width of the intermediate layer and the maximum value of the width of the semiconductor wafer is 0to 10 mm.