CN116134106A - Electronic device manufacturing method - Google Patents

Abstract

A method of manufacturing an electronic device, comprising at least the following steps: step (A), preparing a structure (100), the structure (100) having an electronic component (30) having a circuit forming surface (30A) and bonding Adhesive film (50) on the side of the circuit forming surface (30A) of the electronic component (30); step (B), back grinding the surface of the electronic component (30) opposite to the circuit forming surface (30A) side and step (C), after the adhesive film (50) is irradiated with ultraviolet rays, the adhesive film (50) is removed from the electronic component (30), and the adhesive film (50) has a base material layer (10) and is arranged on the base material In the ultraviolet curable adhesive resin layer (20) on one side of the layer (10), in the step (C), the 60° peel strength of the adhesive film (50) after ultraviolet irradiation measured by the following method is 0.4 Above N/25mm and below 5.0N/25mm. (Method) Using a tensile tester, the adhesive film (50) irradiated with ultraviolet rays is peeled from the electronic component (30) in a 60° direction under the conditions of 23° C. and a speed of 150 mm/min, and the strength at this time (N /25mm) as the 60°peel strength.

Description

Electronic device manufacturing method

technical field

The present invention relates to a method of manufacturing an electronic device.

Background technique

In the manufacturing process of an electronic device, an adhesive film is stuck on the circuit formation surface of an electronic component in order to fix an electronic component or prevent damage to an electronic component in the process of grinding an electronic component.

As such an adhesive film, what laminated|stacked the adhesive resin layer on the base film is used generally.

With the advancement of high-density packaging technology, thinning of electronic components such as semiconductor wafers is required, for example, thinning processing to a thickness of 50 μm or less is required.

As one of such thin-thickness processes, there is a dicing-first method in which, prior to grinding of electronic components, grooves of a predetermined depth are formed on the surface of the electronic components, followed by grinding to separate the electronic components into pieces. In addition, there is also a pre-stealth method, that is, prior to grinding, the inside of the electronic component is irradiated with a laser to form a modified region, and then the electronic component is separated into pieces by grinding.

As a technique related to the adhesive film for such a cutting-first method and an invisible-first method, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2014-75560 ) and Patent Document 2 (Japanese Patent Laid-Open No. 2016-72546 ) can be cited. documented technology.

Patent Document 1 describes a surface protection sheet having an adhesive layer on a substrate and satisfying the following requirements (a) to (d).

(a) The Young's modulus of the above substrate is 450MPa or more;

(b) The storage modulus of the adhesive layer at 25°C is 0.10 MPa or more;

(c) The storage modulus at 50°C of the adhesive layer is 0.20 MPa or less;

(d) The thickness of the above-mentioned pressure-sensitive adhesive layer is 30 μm or more.

It is described in Patent Document 1 that such a surface protection sheet can prevent water from intruding into the protected surface of the workpiece (slag intrusion) from the gap formed by cutting the workpiece during the back grinding process of the workpiece, and prevent the protected surface of the workpiece from being damaged. pollute.

Patent Document 2 describes an adhesive tape for protecting the surface of a semiconductor wafer, characterized in that it has a base resin film and a radiation-curable adhesive layer formed on at least one side of the base resin film, and the base material The resin film has at least one rigid layer with a tensile modulus of 1-10 GPa, and the peeling force of the adhesive layer after radiation curing is 0.1-3.0 N/25mm at a peeling angle of 30°.

Patent Document 2 describes that according to such an adhesive tape for protecting the surface of a semiconductor wafer, it is possible to suppress scratches on the semiconductor chips that are singulated in the backside grinding process of the semiconductor wafer to which the dicing-first method or the stealth-first method is applied. Move (kerf shift), and process the semiconductor wafer without damage or contamination.

prior art literature

patent documents

Patent Document 1: Japanese Unexamined Patent Publication No. 2014-75560

Patent Document 2: Japanese Patent Laid-Open No. 2016-72546

Contents of the invention

The problem to be solved by the invention

According to the studies of the present inventors, for example, in the manufacturing process of electronic devices using the dicing method, the stealth method, etc., when the adhesive film is peeled off from the electronic component after the back grinding process, it is easy to cause residue on the electronic component side. glue.

The present invention was made in view of the above circumstances, and provides a method of manufacturing an electronic device capable of suppressing adhesive residue on the electronic component side when the adhesive film is peeled off from the electronic component after the back grinding step.

method used to solve the problem

The inventors of the present invention have made intensive studies in order to achieve the above-mentioned problems. As a result, it was found that by adjusting the 60° peel strength of the adhesive film after ultraviolet irradiation to a specific range, it is possible to suppress the residual adhesive on the electronic part side when the adhesive film is peeled off from the electronic part after the back grinding process, thereby Complete the present invention.

According to the present invention, a method of manufacturing an electronic device described below is provided.

[1]

A method of manufacturing an electronic device, which at least includes the following steps:

Step (A), preparing a structure including an electronic component having a circuit-forming surface and an adhesive film bonded to the circuit-forming surface side of the electronic component,

A step (B) of back-grinding the surface of the electronic component opposite to the circuit-formed surface, and

Step (C), removing the above-mentioned adhesive film from the above-mentioned electronic component after irradiating the above-mentioned adhesive film with ultraviolet rays,

The adhesive film includes a substrate layer and an ultraviolet curable adhesive resin layer provided on one side of the substrate layer,

In the said process (C), the 60 degree peel strength of the said adhesive film after the ultraviolet-ray irradiation measured by the following method is 0.4 N/25mm or less and 5.0 N/25mm or less.

(method)

Using a tensile tester, the above-mentioned adhesive film irradiated with ultraviolet rays is peeled from the above-mentioned electronic component in a direction of 60° under the conditions of 23°C and a speed of 150mm/min, and the strength (N/25mm) at this time is set to 60° Peel strength.

[2]

According to the manufacturing method of the electronic device described in the above [1],

Above-mentioned operation (A) comprises following operation:

Step (A1), at least one selected from the step (A1-1) of half-cutting the electronic component and the step (A1-2) of irradiating the electronic component with a laser to form a modified layer on the electronic component;

In the step (A2), after the step (A1), the adhesive film is pasted on the circuit-formed surface side of the electronic component.

[3]

According to the method of manufacturing an electronic device described in [1] or [2] above,

In the above-mentioned step (C), after irradiating the above-mentioned adhesive film with ultraviolet rays at a dose of 200 mJ/cm ² or more and 2000 mJ/cm ² or less, the above-mentioned adhesive resin layer is cured by ultraviolet rays to reduce the adhesive force of the above-mentioned adhesive resin layer , removing the above-mentioned adhesive film from the above-mentioned electronic component.

[4]

The method of manufacturing an electronic device according to any one of [1] to [3] above,

The adhesive resin layer includes a (meth)acrylic resin having a polymerizable carbon-carbon double bond in a molecule and a photoinitiator.

[5]

The method of manufacturing an electronic device according to any one of [1] to [4] above,

The thickness of the above-mentioned adhesive resin layer is not less than 5 μm and not more than 300 μm.

[6]

The method of manufacturing an electronic device according to any one of [1] to [5] above,

The resin constituting the above-mentioned substrate layer comprises polyolefin, polyester, polyamide, polyacrylate, polymethacrylate, polyvinyl chloride, polyvinylidene chloride, polyimide, polyetherimide, One or more of ethylene-vinyl acetate copolymer, polyacrylonitrile, polycarbonate, polystyrene, ionomer, polysulfone, polyethersulfone and polyphenylene ether.

Invention effect

According to the present invention, it is possible to provide a method of manufacturing an electronic device capable of suppressing adhesive residue on the electronic component side when the adhesive film is peeled off from the electronic component after the back grinding step.

Description of drawings

FIG. 1 is a cross-sectional view schematically showing an example of the structure of an adhesive film according to an embodiment of the present invention.

2 is a cross-sectional view schematically showing an example of a method of manufacturing an electronic device according to an embodiment of the present invention.

Detailed ways

Embodiments of the present invention will be described below using the drawings. It should be noted that, in all the drawings, the same constituent elements are given common symbols, and explanations thereof are appropriately omitted. In addition, the figure is a schematic view, and the actual size ratio does not match. In addition, unless otherwise specified, "A-B" in a numerical range means A to B and below. In addition, in this embodiment, "(meth)acrylic acid" means acrylic acid, methacrylic acid, or both of acrylic acid and methacrylic acid.

FIG. 1 is a cross-sectional view schematically showing an example of the structure of an adhesive film 50 according to an embodiment of the present invention. 2 is a cross-sectional view schematically showing an example of a method of manufacturing an electronic device according to an embodiment of the present invention.

The method for manufacturing an electronic device according to this embodiment is a method for manufacturing an electronic device that includes at least the following steps: step (A), preparing a structure 100 including an electronic component 30 having a circuit-forming surface 30A and bonding The adhesive film 50 on the circuit formation surface 30A side of the electronic component 30; the process (B), the surface of the electronic component 30 opposite to the circuit formation surface 30A side is subjected to back grinding; and the process (C), the adhesiveness After the film 50 is irradiated with ultraviolet rays, the adhesive film 50 is removed from the electronic component 30. The adhesive film 50 includes the base layer 10 and the ultraviolet-curable adhesive resin layer 20 provided on one side of the base layer 10. In the step (C ), the 60° peel strength of the adhesive film 50 after ultraviolet irradiation (after ultraviolet curing) measured by the following method is 0.4 N/25 mm or more and 5.0 N/25 mm or less.

(Method) Using a tensile tester, the adhesive film 50 irradiated with ultraviolet light is peeled from the electronic component 30 in a 60° direction at 23° C. and a speed of 150 mm/min, and the strength (N/25 mm) at this time is set as 60° peel strength.

As described above, according to the study of the present inventors, for example, in the manufacturing process of electronic devices using the dicing method, the stealth method, etc., when the adhesive film 50 is peeled off from the electronic component 30 after the back grinding process, it is clear that the Adhesive residue tends to be generated on the side of the electronic component 30 .

The reason for this is not clear, but unlike the normal back grinding process of the electronic component 30 , it is necessary to peel off the adhesive film 50 from the cut electronic component 30 , so it is considered that adhesive residue tends to occur at the edge of the cut electronic component 30 .

The inventors of the present invention have made intensive studies in order to achieve the above-mentioned problems. As a result, it was first found that by adjusting the 60° peel strength of the adhesive film 50 after ultraviolet irradiation to a specific range, it is possible to suppress the peeling of the electronic component 30 when the adhesive film 50 is peeled from the electronic component 30 after the back grinding process. Residue.

In the method of manufacturing an electronic device according to this embodiment, from the viewpoint of preventing adhesive residue on electronic components 30 in various surface states, in step (C), the 60° peel strength of the adhesive film 50 after ultraviolet irradiation It is 0.4N/25mm or more and 5.0N/25mm or less, preferably 3.0N/25mm or less, more preferably adjusted to 2.5N/25mm or less.

In the step (C), the 60° peel strength of the adhesive film 50 after irradiating ultraviolet rays can be controlled, for example, by controlling the types, compounding ratios, and adhesive properties of the adhesive resin, crosslinking agent, and photoinitiator constituting the adhesive resin layer 20 . The type and content ratio of each monomer in the resin, and the ultraviolet irradiation conditions (for example, the amount of ultraviolet rays, irradiation intensity, and irradiation time) in the step (C) are controlled within the above-mentioned ranges.

1. Adhesive film

As shown in FIG. 1 , an adhesive film 50 according to the present embodiment includes a base material layer 10 and an ultraviolet curable adhesive resin layer 20 provided on one side of the base material layer 10 .

In view of the balance between mechanical properties and handleability, the overall thickness of the adhesive film 50 according to this embodiment is preferably 50 μm to 600 μm, more preferably 50 μm to 400 μm, and still more preferably 50 μm to 300 μm.

The adhesive film 50 according to the present embodiment may have other layers such as a concavo-convex absorbent resin layer, an adhesive layer, and an antistatic layer (not shown) between layers within a range that does not impair the effect of the present invention. According to the unevenness-absorbing resin layer, the unevenness absorption of the adhesive film 50 can be improved. According to the adhesive layer, the adhesiveness between each layer can be improved. In addition, according to the antistatic layer, the antistatic property of the adhesive film 50 can be improved.

Next, each layer which comprises the adhesive film 50 which concerns on this embodiment is demonstrated.

＜Substrate layer＞

The base material layer 10 is a layer provided for the purpose of improving the handling properties, mechanical properties, and heat resistance of the adhesive film 50 .

The base material layer 10 is not particularly limited as long as it has mechanical strength capable of withstanding an external force applied when processing the electronic component 30 , and examples thereof include a resin film.

As the resin constituting the substrate layer 10, for example, polyolefins selected from polyethylene, polypropylene, poly(4-methyl-1-pentene), poly(1-butene); polyethylene terephthalate; Polyesters such as glycol esters, polybutylene terephthalate, and polyethylene naphthalate; polyamides such as nylon-6, nylon-66, and polyisophthalamide; (meth)acrylic resin; polyvinyl chloride; polyvinylidene chloride; polyimide; polyetherimide; ethylene-vinyl acetate copolymer; polyacrylonitrile; polycarbonate; polystyrene; ionomer; poly One or more of sulfone; polyethersulfone; polyether ether ketone, etc.

Among them, from the viewpoint of improving mechanical properties and transparency, it is preferably selected from polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyamide, polyimide, One or more of ethylene-vinyl acetate copolymer and polybutylene terephthalate, more preferably selected from polyethylene terephthalate and polyethylene naphthalate one or more of two.

The base material layer 10 may be a single layer or two or more layers.

In addition, as the form of the resin film for forming the base material layer 10, it may be a stretched film, or a film stretched in a uniaxial direction or a biaxial direction, but from the viewpoint of improving the mechanical strength of the base material layer 10 In view of this, it is preferably a film stretched in a uniaxial direction or a biaxial direction. From the viewpoint of suppressing warping of the electronic component 30 after grinding, the base material layer 10 is preferably annealed in advance. In order to improve the adhesiveness with other layers, the base material layer 10 may also be surface-treated. Specifically, corona treatment, plasma treatment, under coat treatment, primer coat treatment, and the like can be performed.

From the viewpoint of obtaining good film properties, the thickness of the substrate layer 10 is preferably 20 μm to 250 μm, more preferably 30 μm to 200 μm, and still more preferably 50 μm to 150 μm.

＜Adhesive resin layer＞

The adhesive film 50 which concerns on this embodiment is provided with the ultraviolet-curable adhesive resin layer 20.

The adhesive resin layer 20 is a layer provided on one side of the base material layer 10, and when the adhesive film 50 is attached to the circuit forming surface 30A of the electronic component 30, it contacts and adheres to the circuit forming surface 30A of the electronic component 30. layer.

Examples of the adhesive constituting the adhesive resin layer 20 include (meth)acrylic adhesives, silicone adhesives, urethane adhesives, olefin adhesives, and styrene adhesives. Among them, a (meth)acrylic pressure-sensitive adhesive having a (meth)acrylic resin as a base polymer is preferable from the viewpoint that the adhesive force can be easily adjusted.

In addition, as the adhesive constituting the adhesive resin layer 20 , it is preferable to use an ultraviolet cross-linking type adhesive that reduces adhesive force by ultraviolet rays.

The adhesive resin layer 20 made of an ultraviolet cross-linkable adhesive is cross-linked by irradiation of ultraviolet rays, and the adhesive force is significantly reduced, so that the electronic component 30 is easily peeled from the adhesive film 50 .

Examples of the (meth)acrylic resin contained in the (meth)acrylic adhesive include homopolymers of (meth)acrylate compounds and copolymers of (meth)acrylate compounds and comonomers. wait. Examples of (meth)acrylate compounds include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, ( Hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, etc. These (meth)acrylate compounds may be used alone or in combination of two or more.

In addition, examples of the comonomer constituting the (meth)acrylic copolymer include vinyl acetate, (meth)acrylonitrile, styrene, (meth)acrylic acid, itaconic acid, (meth)acrylamide , hydroxymethyl (meth)acrylamide, maleic anhydride, etc. These comonomers may be used alone or in combination of two or more.

Examples of UV-crosslinkable (meth)acrylic adhesives include adhesives comprising a (meth)acrylic resin having a polymerizable carbon-carbon double bond in the molecule and a photoinitiator, and optionally An adhesive obtained by crosslinking the above (meth)acrylic resin with a crosslinking agent. The ultraviolet crosslinkable (meth)acrylic pressure-sensitive adhesive may further contain a low molecular weight compound having two or more polymerizable carbon-carbon double bonds in the molecule.

Specifically, the (meth)acrylic resin having a polymerizable carbon-carbon double bond in the molecule is obtained as follows. First, a monomer having an ethylenic double bond and a copolymerizable monomer having a functional group (P) are copolymerized. Next, the functional group (P) contained in the copolymer and the monomer having a functional group (Q) capable of addition reaction, condensation reaction, etc. with the functional group (P) are left in a state where the double bond in the monomer The reaction is carried out under the following conditions to introduce polymerizable carbon-carbon double bonds into the copolymer molecules.

Examples of monomers having an ethylenic double bond include methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, butyl (meth)acrylate, ethyl (meth)acrylate, etc. Among monomers having an ethylenic double bond such as alkyl acrylate and alkyl methacrylate monomers, vinyl esters such as vinyl acetate, (meth)acrylonitrile, (meth)acrylamide, and styrene, Use one or more than two.

Examples of the above-mentioned copolymerizable monomer having a functional group (P) include (meth)acrylic acid, maleic acid, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, N-methylol (meth)acrylamide, (meth)acryloxyethyl isocyanate, etc. These may be used alone or in combination of two or more.

The ratio of the monomer having an ethylenic double bond to the copolymerizable monomer having a functional group (P) is preferably 70 to 99% by mass of the monomer having an ethylenic double bond, and the copolymerizable monomer having a functional group (P) The monomer content is 1 to 30% by mass. More preferably, the above-mentioned monomer having an ethylenic double bond is 80 to 95% by mass, and the copolymerizable monomer having a functional group (P) is 5 to 20% by mass.

As a monomer which has the said functional group (Q), the thing similar to the said copolymerizable monomer which has a functional group (P) is mentioned, for example.

As a combination of a functional group (P) and a functional group (Q) that react when a polymerizable carbon-carbon double bond is introduced into a copolymer of a monomer having an ethylenic double bond and a copolymerizable monomer having a functional group (P), it is desirable It is a combination of carboxyl group and epoxy group, carboxyl group and aziridinyl group, hydroxyl group and isocyanate group, etc., which are prone to addition reactions. In addition, it is not limited to addition reactions, such as condensation reactions of carboxylic acid groups and hydroxyl groups, and any reaction can be used as long as it can easily introduce a polymerizable carbon-carbon double bond.

Examples of low molecular weight compounds having two or more polymerizable carbon-carbon double bonds in the molecule include tripropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane Tetraacrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, di(trimethylolpropane)tetraacrylate, and the like. One kind or two or more kinds of them can be used. The amount of the low-molecular-weight compound having two or more polymerizable carbon-carbon double bonds in the molecule is preferably 0.1 to 20 parts by mass, more preferably 5 to 18 parts by mass, based on 100 parts by mass of the above-mentioned (meth)acrylic resin .

Examples of photoinitiators include benzoin, isopropylbenzoin ether, isobutylbenzoin ether, benzophenone, Michler's ketone, chlorothioxanthone, dodecylthioxanthone, Dimethyl thioxanthone, diethyl thioxanthone, acetophenone diethyl ketal, benzil dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl- 1-phenylpropan-1-one, 2-benzyl-2-dimethylamino-4'-morpholinobutyrophenone, 2,2-dimethoxy-2-phenylacetophenone, 2 -Dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)butan-1-one and the like. One kind or two or more kinds of them can be used. The addition amount of a photoinitiator is preferably 0.1-15 mass parts with respect to 100 mass parts of said (meth)acrylic resins, More preferably, it is 1-10 mass parts, More preferably, it is 4-10 mass parts.

A crosslinking agent may be added to the above ultraviolet curable adhesive. Examples of the crosslinking agent include epoxy-based compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether; tetramethylolmethane tri-β- Aziridinylpropionate, Trimethylolpropane Tris-β-Aziridinylpropionate, N,N'-Diphenylmethane-4,4'-Bis(1-Aziridinecarboxamide) , N,N'-hexamethylene-1,6-bis(1-aziridine carboxamide) and other aziridine compounds; tetramethylene diisocyanate, hexamethylene diisocyanate, polyisocyanate and other isocyanates Department of compounds, etc. The above-mentioned ultraviolet curable adhesive may be any of solvent type, emulsion type, hot melt type and the like.

The content of the crosslinking agent is generally preferably within a range in which the number of functional groups in the crosslinking agent is not more than the number of functional groups in the (meth)acrylic resin. However, when a functional group is newly generated by a crosslinking reaction, or when the crosslinking reaction is slow, it may be contained in excess as necessary.

From the viewpoint of improving the balance between the heat resistance of the adhesive resin layer 20 and the adhesive force, the content of the crosslinking agent in the (meth)acrylic adhesive is preferably It is 0.1 to 15 mass parts, preferably 0.5 to 5 mass parts.

The adhesive resin layer 20 can be formed, for example, by applying an adhesive coating liquid on the base material layer 10 .

As a method of applying the adhesive coating liquid, conventionally known coating methods such as roll coating, reverse roll coating, gravure roll coating, bar coating, chipped wheel coating, and die coating can be used, for example. The drying conditions of the applied adhesive are not particularly limited, but generally, it is preferable to dry at a temperature range of 80 to 200° C. for 10 seconds to 10 minutes. More preferably, it is dried at 80 to 170°C for 15 seconds to 5 minutes. In order to sufficiently accelerate the crosslinking reaction between the crosslinking agent and the (meth)acrylic resin, it may be heated at 40 to 80° C. for about 5 to 300 hours after drying of the adhesive coating liquid.

In the adhesive film 50 according to this embodiment, the thickness of the adhesive resin layer 20 is preferably 5 μm to 300 μm, more preferably 10 μm to 100 μm, and still more preferably 10 μm to 50 μm. When the thickness of the adhesive resin layer 20 is in the said range, the balance of the adhesiveness to the surface of the electronic component 30, and handleability will be favorable.

2. Manufacturing method of electronic device

The method of manufacturing an electronic device according to this embodiment includes at least the following three steps.

(A) A step of preparing a structure 100 including an electronic component 30 having a circuit formation surface 30A and an adhesive film 50 bonded to the circuit formation surface 30A side of the electronic component 30 ,

(B) a process of back-grinding the surface of the electronic component 30 opposite to the circuit-forming surface 30A side, and

(C) The process of removing the adhesive film 50 from the electronic component 30 after irradiating the adhesive film 50 with ultraviolet rays.

Furthermore, in the process (C), the 60 degree peel strength of the adhesive film 50 after ultraviolet irradiation is 0.4N/25mm or more and 5.0N/25mm or less, It is characterized by the above-mentioned.

Each step of the method of manufacturing an electronic device according to the present embodiment will be described below.

(Process (A))

First, the structure 100 provided with the electronic component 30 which has 30 A of circuit formation surfaces, and the adhesive film 50 bonded to the circuit formation surface 30A side of the electronic component 30 is prepared.

Such a structure 100 can be produced, for example, by peeling off the release film from the adhesive resin layer 20 of the adhesive film 50, exposing the surface of the adhesive resin layer 20, and pasting the circuit of the electronic component 30 on the adhesive resin layer 20. Surface 30A is formed.

Here, the conditions when attaching the circuit formation surface 30A of the electronic component 30 to the adhesive film 50 are not particularly limited, for example, the temperature may be 20 to 80° C., the pressure may be 0.05 to 0.5 MPa, and the attachment speed may be 0.5 to 20 mm/sec. .

The step (A) preferably further includes a step (A1) and a step (A2), and the step (A1) is selected from the step (A1-1) of half-cutting the electronic component 30 and irradiating the electronic component 30 with laser light to cut the electronic component 30 into half. At least one of the steps (A1-2) of forming the modified layer; the step (A2) is to stick the adhesive film 50 on the circuit formation surface 30A side of the electronic component 30 after the step (A1).

As described above, in the manufacturing process of electronic devices using the dicing-first method, the stealth-first method, etc., scattering and chipping of the electronic component 30 are likely to occur after the back grinding process. The method for manufacturing an electronic device according to this embodiment can be suitably applied to a manufacturing process of an electronic device. Therefore, it is preferable to perform the above-mentioned process (A1-1) which is a dicing-first method, and the said process (A1-2) which is a stealth-first method.

In the process (A2), the adhesive film 50 can be heated and stuck on the circuit formation surface 30A of the electronic component 30. Thereby, the adhesive state of the adhesive resin layer 20 and the electronic component 30 can be made favorable for a long time. Although it does not specifically limit as heating temperature, For example, it is 60-80 degreeC.

Although the operation of sticking the adhesive film 50 to the electronic component 30 may be performed manually, it can generally be performed by an apparatus called an automatic sticking machine equipped with a roll-shaped adhesive film.

Although it does not specifically limit as the electronic component 30 affixed to the adhesive film 50, The electronic component 30 which has 30 A of circuit formation surfaces is preferable. Examples thereof include semiconductor wafers, epoxy molded wafers, molded panels, molded array packages, semiconductor substrates, and the like, and are preferably semiconductor wafers and epoxy molded wafers.

In addition, semiconductor wafers include, for example, silicon wafers, sapphire wafers, germanium wafers, germanium-arsenic wafers, gallium-phosphorous wafers, gallium-arsenic-aluminum wafers, gallium-arsenic wafers, lithium tantalate wafers, etc. . As for the epoxy molded wafer, a wafer produced by an eWLB (Embedded Wafer Level Ball Grid Array, embedded wafer level ball grid array) process, which is one of the production methods of the fan-out WLP, can be cited.

The semiconductor wafer and the epoxy molded wafer having a circuit-forming surface are not particularly limited, and are used, for example, for wafers on which circuits such as wiring, capacitors, diodes, and transistors are formed on the surface. In addition, plasma treatment may be performed on the circuit formation surface.

The circuit formation surface 30A of the electronic component 30 may be formed with unevenness by having bump electrodes or the like, for example.

In addition, the bump electrode is, for example, a bump electrode that is bonded to an electrode formed on the mounting surface when the electronic device is mounted on the mounting surface to form an electrical connection between the electronic device and the mounting surface (a mounting surface such as a printed circuit board). .

Examples of the bump electrodes include ball bumps, printed bumps, stud bumps, plated bumps, and stud bumps. That is, the bump electrodes are generally bump electrodes. These bump electrodes may be used alone or in combination of two or more.

The height and diameter of the bump electrodes are not particularly limited, but are preferably 10 to 400 μm, more preferably 50 to 300 μm, respectively. The bump pitch at this time is also not particularly limited, but is preferably 20 to 600 μm, and more preferably 100 to 500 μm.

Moreover, the kind of metal which comprises a bump electrode is not specifically limited, For example, solder, silver, gold, copper, tin, lead, bismuth, and these alloys etc. are mentioned. The adhesive film 50 is suitably used when the bump electrode is a solder bump. These metal types may be used alone or in combination of two or more.

(Process (B))

Next, the surface (also referred to as the back surface) on the opposite side to the circuit formation surface 30A side of the electronic component 30 is back-polished.

Here, performing back grinding refers to thinning the electronic component 30 to a predetermined thickness without damage.

For example, the structure 100 is fixed to a chuck table of a grinding machine, etc., and the back surface (circuit non-formation surface) of the electronic component 30 is ground.

In such a back grinding operation, the electronic component 30 is ground until the thickness becomes a desired thickness or less. The thickness of the electronic component 30 before grinding is appropriately determined according to the diameter and type of the electronic component 30 , and the thickness of the electronic component 30 after grinding is appropriately determined according to the size of the obtained chip, the type of circuit, and the like.

In addition, when the electronic component 30 is cut in half or a reformed layer is formed by laser irradiation, as shown in FIG. 1 , the electronic component 30 is separated into pieces by the step (B).

It does not specifically limit as a back grinding method, A well-known grinding method can be employ|adopted. Each grinding can be performed while applying water to the electronic component 30 and the grinding stone to cool them. If necessary, at the end of the grinding process, a dry polishing process may be performed as a grinding method that does not use grinding water. After back grinding is complete, chemical etching is performed as needed. Chemical etching is carried out by etching in the group consisting of an acidic aqueous solution containing hydrofluoric acid, nitric acid, sulfuric acid, acetic acid, etc. alone or in combination, an alkaline aqueous solution such as an aqueous potassium hydroxide solution, an aqueous sodium hydroxide solution, etc. A method of immersing the electronic component 30 and the like in a state where the adhesive film 50 is stuck in the liquid. This etching is performed for the purposes of removing strain generated on the back surface of the electronic component 30 , further thinning the electronic component 30 , removing an oxide film, etc., and preprocessing when forming electrodes on the back surface. The etchant is appropriately selected according to the above purpose.

(Process (C))

Next, after irradiating the adhesive film 50 with ultraviolet rays, the adhesive film 50 is removed from the electronic component 30 . In step (C), after the adhesive film 50 is irradiated with ultraviolet rays at a dose of, for example, 200 mJ/cm ² to 2000 mJ/cm ² , the adhesive resin layer 20 is cured by ultraviolet rays, and the adhesive force of the adhesive resin layer 20 is reduced. , the adhesive film 50 is removed from the electronic component 30 .

In addition, ultraviolet irradiation can be performed using ultraviolet rays with a dominant wavelength of 365 nm using, for example, a high-pressure mercury lamp.

The irradiation intensity of ultraviolet rays is, for example, not less than 50 mW/cm ² and not more than 500 mW/cm ² .

Before removing the adhesive film from the electronic component 30, the electronic component 30 may be mounted on a dicing tape or a dicing tape with a wafer adhesive film. Although the operation of removing the adhesive film 50 from the electronic component 30 may be performed manually, it can generally be performed by an apparatus called an automatic peeling machine.

The surface of the electronic component 30 after peeling off the adhesive film 50 may also be washed as needed. Examples of the washing method include wet washing such as water washing and solvent washing, dry washing such as plasma washing, and the like. In the case of wet cleaning, ultrasonic cleaning may also be used in combination. These washing methods can be appropriately selected according to the contamination state of the surface of the electronic component 30 .

(other processes)

After performing the step (A) to the step (C), a step of mounting the obtained semiconductor chip on a circuit board, etc. may be further performed. These steps can be performed based on known information.

As mentioned above, although preferred embodiment of this invention was described, these are illustrations of this invention, and various structures other than the above-mentioned can also be employ|adopted.

Example

Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited to these.

Details about the production of the adhesive film are as follows.

＜Substrate layer＞

Substrate layer 1: polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., product name: E7180, thickness: 50 μm, single-sided corona-treated product)

Substrate layer 2: laminated film comprising low-density polyethylene film/polyethylene terephthalate film/low-density polyethylene film (total thickness: 110 μm)

A low-density polyethylene film (density: 0.925 kg/m ³ , thickness: 30 μm) was laminated on both sides of a polyethylene terephthalate film (manufactured by Toray Corporation, product name: Lumirror S10, thickness: 50 μm) and get. Corona treatment was performed on one side of the obtained laminated film.

Substrate layer 3: laminated film comprising polyethylene terephthalate film/ethylene-vinyl acetate copolymer film/acrylic film (total thickness: 145 μm)

A polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., product name: E7180, thickness: 50 μm) and an ethylene-vinyl acetate copolymer (manufactured by Mitsui Dow Polymer Chemicals Co., Ltd., MFR: 2.5 g/ 10 minutes) film (thickness: 70 μm) was laminated by performing corona treatment on the side of the ethylene-vinyl acetate copolymer film bonded to the polyethylene terephthalate film. Furthermore, corona discharge treatment was also given to the side opposite to the polyethylene terephthalate film of the ethylene-vinyl acetate copolymer film.

Next, on the release surface of the polyethylene terephthalate film (separator) subjected to the release treatment, the following acrylic resin coating solution for the base material was applied to a dry thickness of 20 μm. Cloth and dry, by ethylene-vinyl acetate copolymer film pasting on the laminated film that comprises polyethylene terephthalate film/ethylene-vinyl acetate copolymer film above-mentioned, carry out aging (40 ℃, 3 sky). Next, the separator was peeled off to obtain the base material layer 3 .

<Acrylic resin coating solution for base material>

As a polymerization initiator, 0.5 parts by mass of 4,4'-azobis-4-cyanovaleric acid (manufactured by Otsuka Chemical Co., Ltd., product name: ACVA) was used to make 74 parts by mass of butyl Parts by mass, 9 parts by mass of 2-hydroxyethyl methacrylate, 2 parts by mass of methacrylic acid, 1 part by mass of acrylamide, an aqueous solution of polyoxyethylene nonylpropenylphenyl ether ammonium sulfate (manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd. , product name: Aquaron HS-1025) 3 parts by mass in deionized water, emulsion polymerization at 70°C for 9 hours. After the polymerization, the pH was adjusted to 7 with ammonia water to obtain an acrylic polymer aqueous emulsion with a solid content concentration of 42.5%. Next, with respect to 100 parts by mass of the acrylic polymer aqueous emulsion, ammonia water was used to adjust the pH to 9 or more, and 0.75 parts by mass of an aziridine-based crosslinking agent [manufactured by Nippon Shokubai Chemical Industry Co., Ltd., Chemitite PZ-33], and 5 parts by mass of diethylene glycol monobutyl ether was used to obtain a coating liquid for a substrate.

＜(Meth)acrylic resin solution＞

(Meth)acrylic resin solution 1:

49 parts by mass of ethyl acrylate, 20 parts by mass of 2-ethylhexyl acrylate, 21 parts by mass of methyl acrylate, 10 parts by mass of glycidyl methacrylate, and benzoyl peroxide as a polymerization initiator were polymerized 0.5 mass parts of initiators were reacted at 80 degreeC for 10 hours in 65 mass parts of toluene and 50 mass parts of ethyl acetate. After the reaction was completed, the obtained solution was cooled, and 25 parts by mass of xylene, 5 parts by mass of acrylic acid, and 0.5 parts by mass of tetradecyldimethylbenzyl ammonium chloride were added to the cooled solution, and air was blown in. It reacted at 85 degreeC for 32 hours, and the (meth)acrylic-type resin solution 1 was obtained.

(Meth)acrylic resin solution 2:

77 parts by mass of n-butyl acrylate, 16 parts by mass of methyl methacrylate, 16 parts by mass of 2-hydroxyethyl acrylate, and 0.3 parts by mass of t-butyl peroxy-2-ethylhexanoate as a polymerization initiator One part was reacted at 85 degreeC for 10 hours in 20 mass parts of toluene and 80 mass parts of ethyl acetate. After the reaction was completed, the solution was cooled, and 30 parts by mass of toluene, 7 parts by mass of methacryloyloxyethyl isocyanate (manufactured by Showa Denko, product name: karenz MOI) and 0.05 parts by mass of dibutyltin dilaurate were added thereto. , and reacted at 85° C. for 12 hours while blowing in air to obtain a (meth)acrylic resin solution 2 .

(Meth)acrylic resin solution 3:

30 parts by mass of ethyl acrylate, 11 parts by mass of methyl acrylate, 26 parts by mass of 2-ethylhexyl acrylate, 7 parts by mass of 2-hydroxyethyl methacrylate, and benzyl peroxide as a polymerization initiator 0.8 mass parts of acyl-type polymerization initiators were reacted at 80 degreeC for 9 hours in 7 mass parts of toluene and 50 mass parts of ethyl acetate. After completion of the reaction, the obtained solution was cooled, and 25 parts by mass of toluene was added to the cooled solution to obtain a (meth)acrylic resin solution 3 .

＜Preparation of adhesive film＞

An adhesive coating liquid for an adhesive resin layer was prepared by adding the additives shown in Table 1 to the acrylic resin solution. This coating solution was applied on a polyethylene terephthalate film (separator) subjected to silicone release treatment. Next, it was dried at 120° C. for 3 minutes to form an adhesive resin layer with a thickness of 20 μm, and bonded to the base material layer. For substrate layers 1 and 2, stick to the corona-treated surface. For the base material layer 3, the separator was peeled off and attached to the acrylic layer side. The obtained laminate was heated at 40° C. for 3 days in an oven to produce an adhesive film.

<Evaluation method of adhesive film>

(1) 60° peel strength after UV curing

A silicon mirror wafer (8-inch single-sided mirror wafer) was cut into a size of 50 mm x 100 mm. The wafer mirror surface was subjected to ozone cleaning with a UV ozone cleaning device (manufactured by Technovision, UV-208) (ozone treatment time: 60 seconds). Then, the wafer whose mirror surface of the wafer was wiped with ethanol was used as an adherend wafer.

Under the environment of 23°C and 50% RH, cut the adhesive film into a width of 25 mm, peel off the separator, and use a manual roller to stick the adhesive film to the mirror surface of the adherend wafer through its adhesive resin layer, and leave it for 1 hour . After being left to stand, the adhesive film was irradiated with ultraviolet rays having a dominant wavelength of 365 nm at an ultraviolet quantity of 1080 mJ/cm ² at an irradiation intensity of 100 mW/cm ² using a high-pressure mercury lamp. Then, the adherend wafer with the adhesive film attached was fixed on an adhesion/film peeling analyzer (VPA-2S, manufactured by Kyowa Interface Science Co., Ltd.), and one end of the adhesive film was fixed to the load cell side with a cellophane tape. The adhesive film was peeled from the surface of the adherend wafer at a peeling angle of 60° and a peeling speed of 150 mm/min, and the 60° peeling strength after UV irradiation was determined from the stress at that time. The evaluation was implemented with N=2, and this value was averaged and made into the measured value.

(2) 180°peel strength evaluation

Adhered wafer:

The mirror surface of the silicon mirror wafer (4-inch single-sided mirror wafer) was subjected to ozone cleaning (ozone treatment time: 60 seconds) with a UV ozone cleaning device (manufactured by Technovision, UV-208). Then, the wafer whose mirror surface of the wafer was wiped with ethanol was used as an adherend wafer.

Peel strength before UV irradiation:

Under the environment of 23°C and 50% RH, cut the adhesive film into a width of 50 mm, peel off the separator, and use a manual roller to stick the adhesive film to the mirror surface of the adherend wafer through its adhesive resin layer, and leave it for 1 hour . After standing, use a tensile tester (Shimadzu Corporation, product name: Autograph AGS-X), clamp one end of the adhesive film, and peel off the adherend at a peeling angle of 180 degrees and a peeling speed of 300 mm/min. The adhesive film was peeled off from the surface of the wafer. The stress at this time was measured and converted into N/25mm to obtain the peel strength. The evaluation was implemented with N=2, and this value was averaged and made into the measured value.

Peeling strength after ultraviolet irradiation: Under the environment of 23°C and 50% RH, cut the adhesive film into a width of 50 mm, peel off the separator, and stick the adhesive film to the adherend through its adhesive resin layer using a manual roller The mirror surface of the wafer was placed for 1 hour. After standing, the adhesive film was irradiated with ultraviolet rays having a dominant wavelength of 1080 mJ/cm ² at an irradiation intensity of 100 mW/cm ² under an environment of 25° C. using a high-pressure mercury lamp. Then, using a tensile tester (Shimadzu Corporation, product name: automatic plotter AGS-X), one end of the adhesive film was clamped, and the adhesive film was peeled off from the adherend wafer at a peeling angle of 180 degrees and a peeling speed of 300 mm/min. Peel off the adhesive film on the surface. The stress at this time was measured and converted into N/25mm to obtain the peel strength. The evaluation was implemented with N=2, and this value was averaged and made into the measured value.

Evaluation of residual glue:

The to-be-adhered wafer wafer after said peeling was observed visually, and it evaluated based on the following reference|standard.

〇 (Good): When no adhesive residue is confirmed

× (poor): When residual glue is confirmed

(3) Evaluation of first cutting method

Evaluation Wafer 1:

Using a dicing machine, the mirror surface of a mirror wafer (8-inch mirror wafer, diameter: 200±0.5 mm, thickness: 725±50 μm, single-sided mirror) was half-cut to obtain Evaluation Wafer 1 . (Blade: ZH05-SD3500-N1-70-DD, chip size: 5mm×8mm, incision depth: 58μm, blade rotation speed: 30000rpm). The evaluation wafer 1 was observed with an optical microscope, and the scratch width was 35 μm.

Evaluation Wafer 2:

Use a dicing machine to perform the first-stage half-cut (blade: Z09-SD2000-Y158×0.25A) on the mirror surface of a mirror wafer (8-inch mirror wafer, diameter: 200±0.5mm, thickness: 725±50μm, single-sided mirror) ×40×45E-L, chip size: 5mm×8mm, incision depth: 15μm, blade rotation speed: 30000rpm). Observation with an optical microscope revealed that the scratch width was 60 μm. Next, the second stage of half dicing (blade: ZH05-SD3500-N1-70-DD, chip size: 5mm×8mm, kerf depth: 58μm, blade rotation speed: 30000rpm) was performed to obtain evaluation wafer 2.

Cut first:

Using a tape laminator (Nitto Denko Co., Ltd., DR3000II), the adhesive film was attached to the half-cut surface of the evaluation wafer (23° C., attachment speed: 5 mm/min, attachment pressure: 0.36 MPa).

Next, the above-mentioned wafer was subjected to back grinding (rough cutting and fine cutting, fine cutting amount: 40 μm, no polishing, thickness after grinding: 38 μm) using a grinder (manufactured by DISCO Corporation, DGP8760) to singulate.

Chip flying at the time of dicing first was visually evaluated after performing backside grinding according to the following criteria.

〇 (Good): Chip scattering was not confirmed including the triangular corners

× (poor): Scattering of chips was confirmed including the triangular corners

Furthermore, ultraviolet irradiation and adhesive film peeling were performed, and the residual adhesive after the dicing-first method was evaluated.

In the ultraviolet irradiation, the adhesive film was irradiated with ultraviolet rays having a dominant wavelength of 1080 mJ/cm ² at an irradiation intensity of 100 mW/cm ² using a high-pressure mercury lamp in an environment of 25° C. and 365 nm.

Peeling of the adhesive film was carried out in the following procedure. First, using a wafer mounter (manufactured by Nitto Denko Co., Ltd., MSA300), a separately prepared dicing tape (used as a mounting tape) was attached to the 8-inch wafer ring frame and the above-mentioned sheet through the adhesive surface of the dicing tape. Wafer side of sliced wafer. Next, the adhesive film was peeled off from the wafer notch by using a tape peeler (manufactured by Nitto Denko, HR3000III) with a peeling tape (manufactured by Lasting System, PET38REL). Device detachability was evaluated according to the following criteria.

〇 (good): When the adhesive film can be peeled off from the wafer for the first time

× (poor): Case where the adhesive film could not be peeled from the wafer for the first time

About the adhesive residue on the wafer which was singulated after the dicing method, it evaluated according to the following reference|standard using the optical microscope (made by Olympus Corporation).

〇 (Good): When no adhesive residue is confirmed

× (poor): When residual glue is confirmed

[Example 1]

With respect to 100 parts by mass of (meth)acrylic resin solution 1 (solid content), 2,2-dimethoxy-2-phenylacetophenone (manufactured by IGM Corporation, trade name: omnirad) was added as a photoinitiator. 651) 6.9 parts by mass, and an isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals, trade name: olester P49-75S) 0.93 parts by mass to obtain an adhesive coating liquid 1 for an adhesive resin layer. By the above-mentioned method, an adhesive film was produced. In addition, 60° peel strength evaluation after ultraviolet curing, 180° peel strength evaluation, and first-cut method evaluation were carried out based on the evaluation method described previously. The results are shown in Table 1.

[Examples 2 to 9 and Comparative Examples 1 and 2]

Except having changed the kind of adhesive resin layer and base material layer into the kind shown in Table 1, it carried out similarly to Example 1, and each adhesive film was produced. In addition, each evaluation was performed in the same manner as in Example 1, respectively. The obtained results are shown in Table 1, respectively.

In addition, the compounds described in Table 1 are as follows.

omnirad 651 (manufactured by IGM): 2,2-dimethoxy-2-phenylacetophenone

omnirad 369 (manufactured by IGM): 2-benzyl-2-dimethylamino-4'-morpholinobutyrophenone

aronix M400 (manufactured by Toagosei Co., Ltd.): a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate

NK ESTER AD-TMP (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.): bis(trimethylolpropane) tetraacrylate

[Table 1]

This application claims priority based on Japanese Application Japanese Patent Application No. 2020-125449 filed on July 22, 2020, and the entire disclosure thereof is incorporated herein by reference.

Symbol Description

10 substrate layer

20 layers of adhesive resin

30 electronic components

30A circuit formation surface

50 adhesive film

100 structures.

Claims (6)

1. A method of manufacturing an electronic device, comprising at least the following steps: Step (A), preparing a structure including an electronic component having a circuit-forming surface and an adhesive film bonded to the circuit-forming surface side of the electronic component, A step (B) of back-grinding a surface of the electronic component opposite to the circuit-forming surface, and A step (C) of removing the adhesive film from the electronic component after irradiating the adhesive film with ultraviolet rays, The adhesive film includes a substrate layer and an ultraviolet curable adhesive resin layer provided on one side of the substrate layer, In the step (C), the 60° peel strength of the adhesive film after ultraviolet irradiation measured by the following method is 0.4 N/25 mm or more and 5.0 N/25 mm or less, method: Using a tensile tester, the adhesive film irradiated with ultraviolet rays was peeled from the electronic component in a 60° direction at 23° C. and a speed of 150 mm/min. The strength (N/25 mm) at this time was expressed as 60° peel strength. 2. The method for manufacturing an electronic device according to claim 1, wherein said operation (A) comprises the following operations: The step (A1) is at least one selected from the step (A1-1) of half-cutting the electronic component and the step (A1-2) of irradiating the electronic component with laser light to form a modified layer on the electronic component. A sort of; A step (A2) of sticking the adhesive film on the side of the circuit formation surface of the electronic component after the step (A1). 3. The method of manufacturing an electronic device according to claim 1 or 2, wherein in ^{the step (C), the adhesive film is irradiated with ultraviolet light at a dose of 200 mJ/cm to 2000 mJ/cm 2 ,} so that After the adhesive resin layer is cured with ultraviolet light to reduce the adhesive force of the adhesive resin layer, the adhesive film is removed from the electronic component. 4 . The method of manufacturing an electronic device according to claim 1 , wherein the adhesive resin layer contains a (meth)acrylic resin having a polymerizable carbon-carbon double bond in a molecule and a photoinitiator. 5 . The method for manufacturing an electronic device according to claim 1 , wherein the adhesive resin layer has a thickness of not less than 5 μm and not more than 300 μm. 6. The method for manufacturing an electronic device according to any one of claims 1 to 5, the resin constituting the substrate layer comprises polyolefin, polyester, polyamide, polyacrylate, polymethacrylate , polyvinyl chloride, polyvinylidene chloride, polyimide, polyetherimide, ethylene-vinyl acetate copolymer, polyacrylonitrile, polycarbonate, polystyrene, ionomer, polysulfone One or more of polyethersulfone and polyphenylene ether.

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