TW201936732A - Heat-curable resin film and sheet for forming first protective film - Google Patents

Abstract

The present invention provides a thermosetting resin film 12, which is a thermosetting resin film 12 attached to a surface of a semiconductor wafer having bumps and used for thermosetting to form a first protective film on the surface When the thermosetting resin film 12 before thermosetting is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C is 500 Pa‧s or more. Also provided is a sheet 1 for forming a first protective film, which includes a first support sheet 101 and a thermosetting resin film 12 on a surface 101 a of the first support sheet 101.

Description

Sheet for forming thermosetting resin film and first protective film

The present invention relates to a thermosetting resin film for attaching to a surface of a semiconductor wafer having bumps, by thermosetting it, and forming a first protective film on the surface, and a thermosetting resin film provided with the thermosetting resin film Sheet for forming the first protective film.
This application claims priority based on Japanese Patent Application No. 2017-221986 filed in Japan on November 17, 2017, and the contents are used here.

Conventionally, when mounting a multi-pin LSI package used in MPUs, gate arrays, etc. on a printed wiring board, a flip-chip mounting method can be used, which is formed on the connection pad part by a eutectic solder, high temperature solder Bumps made of gold, gold, etc. (hereinafter, referred to as "bumps" in this specification) are used as semiconductor wafers, and these bumps and wafer mounting substrates are made by a so-called face down method The corresponding terminal parts on the face-to-face, contact, fusion/diffusion bonding.

The semiconductor chip used in this mounting method can be ground, cut, etc. by, for example, the surface of the semiconductor wafer with bumps formed on the circuit surface opposite to the circuit surface (in other words, the bump forming surface) Obtained by slice. In the process of obtaining such a semiconductor wafer, generally, for the purpose of protecting the bump forming surface and the bump of the semiconductor wafer, a curable resin film is attached to the bump forming surface to harden the film, thereby A protective film is formed on the block forming surface (hereinafter, referred to as "first protective film" in this specification).

The curable resin film is usually attached to the bump forming surface of the semiconductor wafer in a state of being softened by heating. In this way, the upper portion of the top of the head including the bumps penetrates the curable resin film and protrudes from the curable resin film. On the other hand, the curable resin film spreads between the bumps so as to cover the bumps of the semiconductor wafer, while being close to the bump forming surface, it covers the surface of the bump, especially in the vicinity of the bump forming surface The surface is embedded in the bumps. After that, the curable resin film is further hardened to cover the bump forming surface of the semiconductor wafer and the surface of the vicinity of the bump forming surface of the bump to become a protective film for protecting these areas. Furthermore, the semiconductor wafer is solidified into a semiconductor wafer, and finally becomes a semiconductor wafer provided with a protective film on the bump forming surface (in this specification, it is referred to as a "semiconductor wafer with protective film").

Such a semiconductor wafer with a protective film is mounted on a substrate to become a semiconductor package, and these semiconductor packages are further used to constitute a target semiconductor device. In order for the semiconductor package and the semiconductor device to function properly, the electrical connection between the bumps of the semiconductor wafer with the protective film and the circuits on the substrate must not be hindered. However, if the curable resin film cannot be properly attached to the bump forming surface of the semiconductor wafer, the protrusion of the bump from the curable resin film becomes insufficient, resulting in a curable resin film remaining on the top of the bump a part of. These curable resin films that remain on the top of the bumps are cured in the same way as the curable resin films in other areas, and become a cured product with the same composition as the protective film (in this specification, it is called "protection" Membrane residue"). In this way, because the top of the bump is the electrical connection area between the bump and the circuit on the substrate, if the amount of the protective film residue is large, it will cause the bump of the semiconductor wafer with the protective film and the substrate The electrical connection of the loop is hindered.
That is, in the stage before mounting on the substrate of the semiconductor wafer with a protective film, it is required that no residue of the protective film exists or the amount of the residue of the protective film is as much as possible on the top of the bump of the semiconductor wafer with the protective film less.

As described above, as a protective film forming sheet capable of forming a protective film without leaving a curable resin film on the upper part of a bump, a curable resin is disclosed at a temperature at which the sheet is attached to a semiconductor wafer The elastic ratio of the storage shear modulus of the film to the storage shear modulus of the buffer layer is limited to a specific range (see Patent Document 1).
[Prior Technical Literature]
[Patent Literature]

Patent Literature 1: Japanese Patent Laid-Open No. 2015-206006

[Problems to be solved by the invention]

The sheets for forming a protective film disclosed in Patent Document 1 limit the physical properties of the curable resin film at this temperature when these sheets are attached to a semiconductor wafer.

However, when a thermosetting curable resin film is thermally cured and a protective film is formed on the bumped surface of the semiconductor wafer, it temporarily melts and liquefies to cause cissing, which may result in poor protective film formation.

Therefore, an object of the present invention is to provide a thermosetting resin film, which is a thermally hardened resin film attached to a surface of a semiconductor wafer having bumps and used to form a first protective film on the surface When the thermosetting resin film is attached to the bumped surface of the semiconductor wafer and thermoset, the shrinkage of the surface of the semiconductor wafer can be suppressed. In addition, an object of the present invention is to provide a sheet for forming a first protective film provided with such a thermosetting resin film.
[Means for solving the problem]

In order to solve the above-mentioned problems, the present invention provides a thermosetting resin film that is attached to a surface of a semiconductor wafer having bumps and is thermoset to form a first protective film on the surface by thermosetting When the above-mentioned thermosetting resin film before thermosetting is heated at 10 °C/min, the minimum value of the shear viscosity at 90 °C ~ 130 °C is 500 Pa‧s or more.

The thermosetting resin film of the present invention preferably contains a polymer component (A) and a thermosetting component (B).
The thermosetting resin film of the present invention preferably contains polyvinyl acetal.

In addition, the present invention provides a sheet for forming a first protective film, which includes a thermosetting resin film described in item 1 of the patent application scope on the surface of one side of the first support sheet.
[Effect of the invention]

According to the present invention, there is provided a thermosetting resin film, which is a thermosetting resin film attached to a surface of a semiconductor wafer having bumps, and by thermosetting it, a first protective film is formed on the surface When the thermosetting resin film is attached to the bumped surface of the semiconductor wafer to thermally cure it, shrinkage of the surface of the semiconductor wafer can be suppressed. In addition, the present invention provides a sheet for forming a first protective film provided with such a thermosetting resin film.

In this specification, "cissing of the surface of the semiconductor wafer" means that the thermosetting resin film is temporarily melted and liquefied to expose the surface of the semiconductor wafer during thermosetting.
In addition, in this specification, the "surface of the semiconductor wafer" refers to the area where the bump surface is subtracted from the surface of the semiconductor wafer having bumps.

1 is a cross-sectional view illustrating an embodiment of a sheet for forming a thermosetting resin film and a first protective film of the present invention. In addition, in the drawings used in the following description, in order to easily understand the characteristics of the present invention, for convenience, the main part may be enlarged, and the dimensional ratio of each constituent element and the like may not necessarily be the same as the actual.

The first protective film forming sheet 1 shown in FIG. 1 includes a first support sheet 101, and a thermosetting resin film 12 is provided on a surface 101 a of the first support sheet 101. More specifically, the first protective film forming sheet 1 includes a buffer layer 13 on the first substrate 11, a thermosetting resin film 12 on the buffer layer 13, and the first substrate 11 and the buffer layer 13 The first support sheet 101.

The sheet for forming the first protective film of the present invention is not limited to the one shown in FIG. 1, and as long as the effect of the present invention is not impaired, as shown in FIG. 1, a part of the configuration may be changed, deleted, or increase.
For example, the sheet for forming the first protective film of the present invention may be the outermost layer on the side opposite to the substrate (in the case of the sheet for forming the first protective film shown in FIG. 1, it is the thermosetting resin film 12 ) With release film.
Next, each layer constituting the sheet for forming the first protective film of the present invention will be described.

◎Thermosetting resin film The thermosetting resin film is used to protect the bump forming surface (in other words, the circuit surface) of the semiconductor wafer and the bumps provided on the bump forming surface.

The thermosetting resin film of the present invention, like the general resin film, is softened by heating, but the thermosetting resin film by further heating has a thermosetting resin film at room temperature compared to the normal temperature before thermosetting, The property of hardening when returning to normal temperature after heat hardening. In this way, the first protective film formed on the surface having the bump has a function as a protective film. Then, when the temperature of the thermosetting resin film before thermosetting is increased at 10°C/min, the minimum value of the shear viscosity at 90°C to 130°C is 500 Pa‧s or more, which is attached to the semiconductor wafer The surface with bumps does not melt or liquefy when it is thermally hardened, and prevents the formation of a protective film caused by shrinkage.
In addition, in this specification, the "normal temperature" refers to a temperature that is not particularly cold or particularly hot, that is, an ordinary temperature, and examples thereof include, for example, a temperature of 15 to 25°C.

The "shear viscosity" in this manual refers to the use of a shear viscosity measuring device to bring the measuring jig into contact with the upward facing surface of a sample on a cylinder with a diameter of 25 mm and a thickness of 500 μm at a frequency of 1 Hz and a heating rate of 10 °C/ The measurement condition of min is the value measured every 1 second from room temperature to 150°C.
In addition, the "room temperature" in this specification refers to a general temperature in a room, and may include, for example, a temperature of 5°C to 30°C.

The thermosetting resin film for forming the first protective film on the surface of the semiconductor wafer with bumps, in order to suppress the remaining of the thermosetting resin film on the upper part of the bumps (the top of the bumps and the vicinity thereof) Usually, the shear viscosity during heating is set below a certain value to improve the fluidity. However, when the shear viscosity of the thermosetting resin film at the time of heat curing is small, it becomes liquid due to heating, causing agglomeration near the bumps, and the shrinkage failure of the first protective film is likely to occur. Since the temperature at which the thermosetting resin film becomes the lowest shear viscosity will vary depending on its composition, if it becomes the lowest shear viscosity at the curing temperature (heating setting temperature), it may become the lowest shear at a lower temperature. Viscosity. When the thermosetting resin film is heat-cured, shrinkage is likely to occur when the shear viscosity is less than 500 Pa‧s, so the minimum value of the shear viscosity in the heat-hardening temperature range (heating start temperature to heating target temperature) is required Above 500Pa‧s.

Therefore, when the above thermosetting resin film before thermosetting is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C must be 500 Pa‧s or more, preferably 1000 Pa‧s or more , More preferably 2000Pa‧s or more, 10 ⁴ Pa‧s or more, and 2×10 ⁴ Pa‧s or more.

When the above thermosetting resin film before thermosetting is heated at 10 °C/min, the minimum shear viscosity at 90 °C ~ 130 °C, in order to suppress the thermosetting resin film attached to the semiconductor wafer has On the surface of the bump, the residual of the thermosetting resin film on the upper part of the bump is preferably 10 ⁶ Pa‧s or less, more preferably 10 ⁵ Pa‧s or less, 6×10 ⁴ Pa‧s The following are best.

When the above-mentioned thermosetting resin film before thermosetting is heated at 10°C/min, the minimum value of the shear viscosity at 90°C to 130°C is preferably 500 to 10 ⁶ Pa‧s, and preferably 1000 to 10 ⁵ Pa‧s is better, 2000 to 10 ⁵ Pa‧s or less is even better, 10 ⁴ to 10 ⁵ Pa‧s is particularly good, and 2×10 ⁴ to 6×10 ⁴ Pa‧s is the best .

The thermosetting resin film is in the form of a sheet or a film, and as long as the above-mentioned conditions are satisfied, its constituent material is not particularly limited.

The thermosetting resin film preferably contains a resin component and a filler, and preferably contains a resin component, and the content of the filler relative to the total mass of the thermosetting resin film is preferably 45% by mass or less, preferably 5 to 45% by mass is even better.
In addition, in the thermosetting resin film, the weight average molecular weight of the resin component is preferably 1,000,000 or less, and may be, for example, any one of 800,000 or less, 500,000 or less, 300,000 or less, 200,000 or less, 100,000 or less, and 50,000 or less.
On the other hand, in the thermosetting resin film, the lower limit of the weight average molecular weight of the resin component is not particularly limited, but may be, for example, any one of 1,000 or more, 5000 or more, and 8000 or more.
In addition, in the thermosetting resin film, the weight average molecular weight of the resin component is, for example, 1000 to 1000000, 5000 to 800000, 8000 to 500,000, 8000 to 300000, 8000 to 200000, 8000 to 100000, 8000 to 50000, 8000 to Any one of 30,000 or the like is preferable.
When the above-mentioned resin component satisfies these conditions, the effect of suppressing the remaining of the thermosetting resin film on the upper portion of the bump of the first protective film forming sheet is further improved.
In addition, in this specification, unless otherwise specified, the weight average molecular weight means a polystyrene conversion value measured by gel permeation chromatography (GPC).

The thermosetting resin film preferably contains a resin component, and the content of the filler is 45% by mass or less relative to the total mass of the thermosetting resin film, and the weight average molecular weight of the resin component is 30,000 or less; Preferably, the content of the filler is 5 to 45% by mass relative to the total mass of the thermosetting resin film, and the weight average molecular weight of the resin component is 8000 to 30,000. By satisfying these conditions, the effect of suppressing the remaining of the thermosetting resin film on the bump upper portion of the first protective film forming sheet becomes more enhanced.
The types of the resin components and fillers are not particularly limited.

The thermosetting resin film can be formed using a composition for forming a thermosetting resin film containing its constituent material.

As a preferable thermosetting resin film, for example, those containing a polymer component (A) as the above-mentioned resin component and further containing a thermosetting component (B).

The thermosetting resin film may be only one layer (single layer) or plural layers of more than two layers. When the thermosetting resin film is 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 thermosetting resin film is preferably from 1 to 100 μm, more preferably from 5 to 75 μm, and particularly preferably from 5 to 50 μm. When the thickness of the thermosetting resin film is equal to or greater than the above lower limit, a first protective film with higher protective energy can be formed. In addition, when the thickness of the thermosetting resin film is equal to or less than the above upper limit value, the excessive thickness can be suppressed.
Here, the "thickness of the thermosetting resin film" refers to the thickness of the entire thermosetting resin film, for example, the thickness of the thermosetting resin film formed by a plurality of layers refers to the constituent of the thermosetting resin film The total thickness of all layers.
In addition, as a method for measuring the thickness of the thermosetting resin film, for example, a method of measuring the thickness of the thermosetting resin film at any five locations using a contact thickness gauge and calculating the average of the measured values, etc. . Hereinafter, the measurement method of "thickness" in this specification may include the same method.

<<Composition for Thermosetting Resin Film Formation>>
The thermosetting resin film can be formed using a composition for forming a thermosetting resin film containing its constituent material. For example, the thermosetting resin film-forming composition can be formed on the target portion by applying the thermosetting resin film forming composition to the surface to be formed of the thermosetting resin film and drying if necessary. A more specific method for forming the thermosetting resin film will be described in detail later together with the method for forming other layers. In the thermosetting resin film forming composition, the ratio of the contents of components (also referred to as solid content) that does not vaporize at ordinary temperature is generally the same as the ratio of the contents of the above components of the thermosetting resin film.

The application of the composition for thermosetting resin film formation can be performed by a conventional method, and examples include air knife coaters, blade coaters, bar coaters, gravure coaters, and roll coaters. Cloth machine, roll coater, curtain coater, die coater, knife coater, screen coater, Meyer bar coater (meyer bar coater), anastomotic coater ( kiss coater) and other coating methods.

Although the drying conditions of the thermosetting resin film forming composition are not particularly limited, when the thermosetting resin film forming composition contains the following solvent, it is preferable to heat and dry it. In this case, for example, It is better to dry at 70~130℃ for 10 seconds~5 minutes.

<Composition for resin layer formation>
Examples of the composition for thermosetting resin film formation include, for example, a composition for thermosetting resin film formation containing a polymer component (A) and a thermosetting component (B) (in this specification, it may be abbreviated sometimes). "Composition for resin layer formation") etc.

[Polymer component (A)]
The polymer component (A) is a polymer compound for imparting film-forming properties and flexibility to the thermosetting resin film, and the polymerizable compound is considered to be a component formed by polymerization reaction. In addition, in this specification, the polymerization reaction also includes a polycondensation reaction.
The polymer component (A) contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When the polymer component (A) is two or more types, the combination and ratio of these can be arbitrarily selected.

Examples of the polymer component (A) include polyvinyl acetal, acrylic resin, polyester, urethane resin, urethane acrylate resin, silicone resin, rubber resin, Phenoxy resin, thermoplastic polyimide, etc., are easy to adjust the temperature range in the process of heat curing, that is, the shear viscosity at 90 ℃ ~ 130 ℃, and attach the thermosetting resin film From the viewpoint of improving the effect of suppressing the shrinkage of the surface of the semiconductor wafer when the surface of the semiconductor wafer having bumps is thermally hardened, polyvinyl acetal and acrylic resin are preferred.

In the polymer component (A), the above-mentioned polyvinyl acetal may be a conventional one.
Among them, preferred polyvinyl acetals include, for example, polyvinyl formal and polyvinyl butyral, and polyvinyl butyral is more preferred.
Examples of polyvinyl butyral include those having structural units represented by the following formulas (i)-1, (i)-2, and (i)-3. From the viewpoint of easy adjustment of the temperature range during the thermal hardening process, that is, the shear viscosity at 90°C to 130°C, the polyvinyl butyral has the following formulas (i)-1 and (i )-2 and (i)-3 are preferred as the structural unit. In addition, from the viewpoint of attaching a thermosetting resin film to a bumped surface of a semiconductor wafer and thermosetting it, the effect of suppressing the shrinkage of the surface of the semiconductor wafer is improved. It is preferable to have a structural unit represented by the following formulas (i)-1, (i)-2, and (i)-3.

[Chemical 1]

In the formula, l ₁ , m ₁ and n ₁ are the content ratio (mol%) of each constituent unit.

The weight average molecular weight (Mw) of the polyvinyl acetal is preferably 5,000 to 200,000, more preferably 8,000 to 100,000, even more preferably 9,000 to 80,000, and particularly preferably 10,000 to 50,000. With the weight average molecular weight of polyvinyl acetal in this range, when the thermosetting resin film before curing is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C can be easily adjusted to When 500Pa‧s or more, the thermosetting resin film is attached to the bumped surface of the semiconductor wafer, and when it is thermally cured, the effect of suppressing the shrinkage of the surface of the semiconductor wafer is further improved. In addition, the effect of suppressing the remaining of the thermosetting resin film on the upper part of the bump (the top of the bump and its vicinity) becomes more improved.

The content ratio l ₁ (butyralization degree) of the constituent unit of the butyral group is preferably 40 to 90 mol%, more preferably 50 to 85 mol%, and particularly preferably 60 to 76 mol%.

The content ratio m ₁ of the structural unit having an acetyl group is preferably 0.1 to 9 mol%, more preferably 0.5 to 8 mol%, and particularly preferably 1 to 7 mol%.

The content ratio n ₁ of the structural unit having a hydroxyl group is preferably 10 to 60 mol%, more preferably 10 to 50 mol%, and particularly preferably 20 to 40 mol%.

The glass transition temperature (Tg) of polyvinyl acetal is preferably 40 to 80°C, and more preferably 50 to 70°C. With the Tg of the polyvinyl acetal in this range, when the thermosetting resin film is attached to the surface of the semiconductor wafer with bumps, the effect of suppressing the residual of the thermosetting resin film on the upper part of the bumps becomes To be more improved. In addition, when the Tg is in this range, the first protective film after heat curing with sufficient hardness can be obtained.
In this specification, "glass transition temperature (Tg)" refers to the DSC curve of a sample measured using a differential scanning calorimeter, and is expressed as the temperature of the inversion point of the obtained DSC curve.

The ratio of three or more types of monomers constituting the polyvinyl acetal can be arbitrarily selected.

Examples of the acrylic resin in the polymer component (A) include conventional acrylic polymers.
The weight average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. With the weight average molecular weight of the acrylic resin in this range, when the thermosetting resin film before curing is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C can be easily adjusted to 500 Pa ‧For more than s, when the thermosetting resin film is attached to the bumped surface of the semiconductor wafer, and it is thermally cured, the effect of suppressing the shrinkage of the surface of the semiconductor wafer is further improved. In addition, the shape stability is good, and the thermosetting resin film easily adheres to the uneven surface of the adherend, further suppressing the occurrence of voids and the like between the adherend and the thermosetting resin film.

The glass transition temperature (Tg) of acrylic resin is preferably -50~70℃, more preferably -30~50℃. When the Tg of the acrylic resin is equal to or higher than the above lower limit, the adhesive force between the first protective film and the first support sheet can be suppressed, and the peelability of the first support sheet can be improved. In addition, when the Tg of the acrylic resin is equal to or less than the above upper limit value, the adhesion of the thermosetting resin film and the first protective film to the adherend can be improved.

Examples of the acrylic resin include, for example, one kind or two or more kinds of (meth)acrylate polymers; other than the (meth)acrylate, one or more kinds are selected from (meth)acrylic acid, Iraqi Copolymers made by copolymerizing monomers such as acetic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide, etc.
In addition, in this specification, "(meth)acrylic acid" is a concept containing both "acrylic acid" and "methacrylic acid". Similar terms to (meth)acrylic acid have the same meaning, for example, "(meth)acrylate" is a concept that includes both "acrylate" and "methacrylate", "(meth)acryloyl""Is a concept that includes both "acryloyl" and "methacryloyl".

Examples of the (meth)acrylate constituting the acrylic resin include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and (meth)acrylic acid. Propyl ester, n-butyl (meth)acrylate, isobutyl (meth)acrylate, secondary butyl (meth)acrylate, tertiary butyl (meth)acrylate, pentyl (meth)acrylate, ( Hexyl meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, (meth)acrylic acid N-nonyl ester, isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (also known as lauryl (meth)acrylate) , Tridecyl (meth)acrylate, tetradecyl (meth)acrylate (also known as myristyl (meth)acrylate), pentadecyl (meth)acrylate, cetyl (meth)acrylate ( Also known as (meth)acrylic acid palm ester), (meth)acrylic acid heptadecyl ester, (meth)acrylic acid octadecyl ester (also known as (meth)acrylic stearyl ester), etc. constituting the alkyl ester The alkyl group is a chain structure alkyl (meth)acrylate having 1 to 18 carbon atoms;
(Meth)acrylic acid cyclopentyl (meth)acrylate, isocamphenyl (meth)acrylate, dicyclopentyl (meth)acrylate;
Aralkyl (meth)acrylates such as benzyl (meth)acrylate;
Cycloalkenyl (meth)acrylate such as dicyclopentenyl (meth)acrylate;
(Meth)acrylic acid cycloalkenyloxyalkyl esters such as (meth)acrylic acid dicycloalkenyloxyethyl esters;
(Meth)acrylic acid imide;
Glycidyl group-containing (meth)acrylates such as glycidyl (meth)acrylate;
Hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy (meth)acrylate Hydroxyl-containing (meth)acrylates such as butyl ester, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate;
Substituted amine group-containing (meth)acrylates such as N-methylaminoethyl (meth)acrylate. Here, the "substituted amine group" refers to a group in which one or two hydrogen atoms of the amine group are substituted with groups other than hydrogen atoms.

The monomer constituting the acrylic resin may be only one kind, or two or more kinds. When there are two or more monomers constituting the acrylic resin, these combinations and ratios can be arbitrarily selected.

The acrylic resin may also have functional groups that can bond with other compounds, such as vinyl groups, (meth)acryloyl groups, amine groups, hydroxyl groups, carboxyl groups, and isocyanate groups. The above-mentioned functional group of the acrylic resin may be bonded to other compounds through the following crosslinking agent (F), or may be directly bonded to other compounds without passing through the crosslinking agent (F). Since the acrylic resin is bonded to other compounds through the above functional groups, the reliability of the encapsulation obtained by using the first protective film forming sheet tends to be improved.

In the present invention, for example, as the polymer component (A), a thermoplastic resin other than polyvinyl acetal and acrylic resin (hereinafter, sometimes simply referred to as "thermoplastic resin") may be used without using polyvinyl acetal and acrylic In the case of a system resin, it is used alone, and it can also be used together with polyvinyl acetal or acrylic resin. By using the above thermoplastic resin, the releasability of the first protective film from the first support sheet is improved, the thermosetting resin film becomes easier to adhere to the uneven surface of the adherend, and the adherence and thermosetting properties are further suppressed The occurrence of holes and the like between resin films.

The weight average molecular weight of the thermoplastic resin is preferably 1,000 to 100,000, preferably 3,000 to 80,000.

The glass transition temperature (Tg) of the thermoplastic resin is preferably -30 to 150°C, and more preferably -20 to 120°C.

Examples of the thermoplastic resin include polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, and polystyrene.

The thermoplastic resin contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind, or two or more kinds. When there are two or more thermoplastic resins, these combinations and ratios can be arbitrarily selected.

In the composition for forming a resin layer, the ratio of the content of the polymer component (A) to the total content of all components other than the solvent (total mass of the solid content of the composition for forming a resin layer) (ie, thermosetting resin) The content of the polymer component (A) of the film), regardless of the type of the polymer component (A), preferably 5 to 85% by mass, more preferably 5 to 80% by mass, for example, 5 to 70% by mass %, 5-60% by mass, 5-50% by mass, 5-40% by mass, and 5-30% by mass. However, these contents in the composition for forming a resin layer are only examples.

The polymer component (A) may correspond to the thermosetting component (B). In the present specification, when the composition for forming a resin layer contains components corresponding to both the polymer component (A) and the thermosetting component (B), it is considered that the composition for forming a resin layer contains the polymer component (A ) And thermosetting component (B).

[Thermosetting component (B)]
The thermosetting component (B) is a component for curing the thermosetting resin film to form a hard first protective film.
The thermosetting component (B) contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When the thermosetting component (B) is two or more types, these combinations and ratios can be arbitrarily selected.

Examples of the thermosetting component (B) include, for example, epoxy-based thermosetting resin, thermosetting polyimide, polyurethane, unsaturated polyester, silicone resin, etc., epoxy-based thermosetting resin Better.

(Epoxy thermosetting resin)
The epoxy-based thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).
The epoxy-based thermosetting resin contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When there are two or more epoxy-based thermosetting resins, these combinations and ratios can be arbitrarily selected.

‧Epoxy resin (B1)
Examples of the epoxy resin (B1) include conventional ones, for example, polyfunctional epoxy resin, biphenyl compound, bisphenol A diglycidyl ether and its hydrogenated product, o-cresol novolac epoxy resin, dicyclopentane Diene-type epoxy resins, biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, phenylene skeleton-type epoxy resins, etc., and more than two functional epoxy compounds.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group can also be used. Epoxy resins having unsaturated hydrocarbon groups have higher compatibility with acrylic resins than epoxy resins having no unsaturated hydrocarbon groups. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of the package obtained by using the first protective film forming sheet is improved.

Examples of the epoxy resin having an unsaturated hydrocarbon group include, for example, compounds in which a part of epoxy groups of a multifunctional epoxy resin is converted into a group having an unsaturated hydrocarbon group. Such compounds can be obtained, for example, by addition reaction of (meth)acrylic acid or its derivatives to epoxy groups.
In addition, examples of the epoxy resin having an unsaturated hydrocarbon group include, for example, compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring constituting the epoxy resin.
The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include methine (also referred to as vinyl), 2-propenyl (also referred to as allyl), and (meth)acryloyl Group, (meth) acrylamide group, etc., preferably acryl group.

The weight average molecular weight of the epoxy resin (B1) is preferably 15,000 or less, more preferably 10,000 or less, and particularly preferably 5,000 or less. When the weight average molecular weight of the epoxy resin (B1) is equal to or less than the above upper limit, when the thermosetting resin film before curing is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C The value can be easily adjusted to 500 Pa‧s or more, and the thermosetting resin film is attached to the surface of the semiconductor wafer with bumps, and when it is thermally cured, the effect of suppressing the shrinkage of the surface of the semiconductor wafer becomes more improve. In addition, at the top of the bump, the effect of suppressing the residue of the first protective film becomes more enhanced.

The lower limit of the weight average molecular weight of the epoxy resin (B1) is not particularly limited. However, from the viewpoint of improving the curability of the thermosetting resin film, and the strength and heat resistance of the first protective film, the weight average molecular weight of the epoxy resin (B1) is preferably 300 or more, more preferably 500 or more .

The weight-average molecular weight of the epoxy resin (B1) can be arbitrarily combined with the above-mentioned preferred lower limit and upper limit so as to be appropriately adjusted so as to fall within a set range.
For example, in one embodiment, the weight average molecular weight of the epoxy resin (B1) is preferably 300 to 15,000, more preferably 300 to 10,000, and particularly preferably 300 to 3000. In addition, in one embodiment, the weight average molecular weight of the epoxy resin (B1) is preferably 500-15000, more preferably 500-10000, and particularly preferably 500-3000. However, these are only examples of preferred weight average molecular weight of the epoxy resin (B1).

The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000 g/eq, more preferably 130 to 800 g/eq.
In this specification, the "epoxy equivalent" refers to the gram number (g/eq) of an epoxy compound containing 1 gram equivalent of epoxy groups, and can be measured according to the method of JIS K 7236:2001.

The epoxy resin (B1) is preferably one that is liquid at ordinary temperature (in this specification, it is sometimes simply referred to as "liquid epoxy resin (B1)"). When a liquid epoxy resin is used at normal temperature, it is preferable from the viewpoint of easy adjustment of the shear viscosity.

One type of epoxy resin (B1) may be used alone, or two or more types may be used in combination. When two or more epoxy resins (B1) are used in combination, these combinations and ratios can be arbitrarily selected.

The ratio of the liquid epoxy resin (B1) among the epoxy resin (B1) contained in the composition for forming a resin layer and the thermosetting resin film is 40% relative to the total mass of the epoxy resin (B1) % Or better, more preferably 50% by mass or more, and particularly preferably 55% by mass or more, for example, any one of 60% by mass or more, 70% by mass or more, 80% by mass or more, and 90% by mass or more . With the above ratio above the lower limit, when the thermosetting resin film before curing is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C can be easily adjusted to 500 Pa At least s, when the thermosetting resin film is attached to the surface of the semiconductor wafer having bumps, and it is thermoset, the effect of suppressing the shrinkage of the surface of the semiconductor wafer is further improved. In addition, at the top of the bump, the effect of suppressing the residue of the first protective film becomes more enhanced.
The upper limit of the above ratio is not particularly limited, but the above ratio is preferably 100% by mass or less.
The ratio of the liquid epoxy resin (B1) among the epoxy resin (B1) contained in the composition for forming a resin layer and the thermosetting resin film is 40% relative to the total mass of the epoxy resin (B1) % Or more and 100% by mass or less are preferable, 50% by mass or more and 100% by mass or less are more preferable, and 55% by mass or more and 100% by mass or less are particularly preferable.
Among the epoxy resin (B1) contained in the composition for forming a resin layer and the thermosetting resin film, the ratio of the liquid epoxy resin (B1) to the total mass of the epoxy resin (B1) may be Any one of 60 mass% or more and 100 mass% or less, 70 mass% or more, 100 mass% or less, 80 mass% or more, 100 mass% or less, 90 mass% or more and 100 mass% or less.

‧Heat hardener (B2)
The thermal hardener (B2) has a function as a hardener for the epoxy resin (B1).
Examples of the thermosetting agent (B2) include compounds having two or more functional groups that can react with epoxy groups in one molecule. Examples of the above functional groups include phenolic hydroxyl groups, alcoholic hydroxyl groups, amine groups, carboxyl groups, and acidified groups such as acid groups. Phenolic hydroxyl groups, amine groups, or acidified groups are preferably acidified groups. , Phenolic hydroxyl or amine groups are more preferred.

Among the thermosetting agents (B2), examples of the phenolic curing agent having a phenolic hydroxyl group include, for example, polyfunctional phenol resin, biphenol, phenolic phenol resin, dicyclopentadiene phenol resin, and aralkyl type Phenol resin etc.
Among the thermal hardeners (B2), examples of the amine-based hardener having an amine group include dicyandiamine (abbreviated as "DICY" in this specification).

The thermal hardener (B2) may also have an unsaturated hydrocarbon group.
As the thermosetting agent (B2) having an unsaturated hydrocarbon group, for example, a compound in which a part of the hydroxyl group of a phenol resin is substituted by a group having an unsaturated hydrocarbon group, and the unsaturated ring directly bonded to the aromatic ring of the phenol resin has unsaturated Hydrocarbon-based compounds.
The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having an unsaturated hydrocarbon group.

In the case of using a phenol-based hardener as the thermosetting agent (B2), from the viewpoint of improving the peelability of the first protective film from the first support sheet, the thermosetting agent (B2) uses a softening point or glass transition High temperature is better.

Among the thermosetting agents (B2), for example, the number average molecular weight of resin components such as polyfunctional phenol resins, phenolic phenol resins, dicyclopentadiene phenol resins, and aralkyl phenol resins is preferably 300 to 30,000. 400~10000 is better, 500~3000 is especially good.
In this specification, "number average molecular weight", unless otherwise specified, refers to the number average molecular weight expressed by the value converted from standard polystyrene measured by gel permeation chromatography (GPC).
Among the thermosetting agents (B2), for example, although the molecular weight of non-resin components such as biphenol and dicyandiamide is not particularly limited, it is preferably 60 to 500, for example.

One type of thermosetting agent (B2) may be used alone, or two or more types may be used in combination. When two or more thermosetting agents (B2) are used in combination, these combinations and ratios can be arbitrarily selected.

In the composition for forming a resin layer and the thermosetting resin film, the content of the thermosetting agent (B2) is preferably 0.1 to 500 parts by mass relative to 100 parts by mass of the epoxy resin (B1), and 1 to 200 parts by mass is more preferable, for example, any one of 1 to 150 parts by mass, 1 to 100 parts by mass, 1 to 75 parts by mass, 1 to 50 parts by mass, and 1 to 30 parts by mass. When the content of the thermosetting agent (B2) is at least the above lower limit value, it becomes easier to cure the thermosetting resin film. In addition, when the content of the thermosetting agent (B2) is equal to or less than the upper limit, the moisture absorption rate of the thermosetting resin film is reduced, and the reliability of the package obtained using the first protective film can be improved.

In the composition for forming a resin layer and the thermosetting resin film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) relative to the polymer component The content of (A) is 100 parts by mass, preferably 50 to 1000 parts by mass, more preferably 60 to 950 parts by mass, and particularly preferably 70 to 900 parts by mass. With the above content of the thermosetting component (B) in these ranges, the adhesive force between the first protective film and the first support sheet is suppressed, and the peelability of the first support sheet can be improved.

[Hardening accelerator (C)]
The composition for forming a resin layer and the thermosetting resin film may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the composition for forming a resin layer.
Preferred curing accelerators (C) include, for example, tertiary amines such as triethylenediamine, dimethylbenzylamine, triethanolamine, dimethylamineethanol, ginseng (dimethylaminomethyl)phenol, etc. ; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5 -Imidazoles such as hydroxymethylimidazole (imidazoles in which one or more hydrogen atoms are replaced by groups other than hydrogen atoms); organic phosphines such as tributylphosphine, diphenylphosphine, and triphenylphosphine (one or more) (Phosphine in which the hydrogen atom is substituted by an organic group); tetraphenyl boron salts such as tetraphenylphosphonium tetraphenylphosphonate, triphenylphosphine tetraphenylborate, etc.

The curing accelerator (C) contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When the hardening accelerator (C) is two or more types, these combinations and ratios can be arbitrarily selected.

When a curing accelerator (C) is used, the content of the curing accelerator (C) in the composition for forming a resin layer and the thermosetting resin film is 100 parts by mass relative to the content of the thermosetting component (B), It is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass. When the content of the hardening accelerator (C) is equal to or higher than the above lower limit, the effect achieved by using the hardening accelerator (C) becomes more remarkable.
In addition, when the content of the hardening accelerator (C) is equal to or less than the above upper limit, for example, the highly polar hardening accelerator (C) suppresses the adhesion between the adherend and the adherend in the thermosetting resin film under high temperature and high humidity conditions Then, the interface side moves and the effect of segregation becomes higher, and the reliability of the package obtained by using the first protective film forming sheet is further improved.

[Filling material (D)]
The composition for forming a resin layer and the thermosetting resin film may contain a filler (D). When the thermosetting resin film contains the filler (D), the first protective film obtained by curing the thermosetting resin film becomes easy to adjust the thermal expansion coefficient. Then, by optimizing the thermal expansion coefficient corresponding to the object to be formed of the first protective film, the reliability of the package obtained by using the first protective film forming sheet is improved. In addition, by containing the filler (D) in the thermosetting resin film, the moisture absorption rate of the first protective film can be reduced, and the heat release property can be improved.

The filler (D) may be either an organic filler or an inorganic filler, but an inorganic filler is preferred. Preferred inorganic fillers include, for example, powders such as silicon oxide, alumina, talc, calcium carbonate, titanium white, red lead, silicon carbide, and boron nitride; beads in which these inorganic fillers are spherical Particles; surface modified products of these inorganic fillers; single crystal fibers of these inorganic fillers; glass fibers, etc.
Among these, the inorganic filler is preferably silicon oxide or aluminum oxide.

The filler (D) contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind, or two or more kinds. When there are two or more fillers (D), these combinations and ratios can be arbitrarily selected.

The average particle diameter of the filler (D) is preferably 1 μm or less, more preferably 0.5 μm or less, and particularly preferably 0.1 μm or less. When the average particle diameter of the filler (D) is equal to or lower than the above upper limit, the minimum value of the shear viscosity at 90°C to 130°C when the thermosetting resin film before curing is heated at 10°C/min It becomes easy to adjust to 500Pa‧s or more. When the thermosetting resin film is attached to the bumped surface of the semiconductor wafer to thermally cure it, the effect of suppressing the shrinkage of the surface of the semiconductor wafer becomes more enhanced .
In addition, at the top of the bump, the effect of suppressing the residue of the first protective film becomes more enhanced.
In addition, in this specification, the "average particle diameter", unless otherwise specified, refers to the particle diameter at a cumulative value of 50% (D ₅₀ ) in the particle size distribution curve obtained by the laser diffraction scattering method Value.

The lower limit of the average particle diameter of the filler (D) is not particularly limited. For example, the average particle diameter of the filler (D) is preferably 0.01 μm or more from the viewpoint of easy availability of the filler (D).
The average particle diameter of the filler (D) is preferably 0.01 μm or more and 1 μm or less, more preferably 0.01 μm or more and 0.5 μm or less, and particularly preferably 0.01 μm or more and 0.1 μm or less.

When the filler (D) is used, in the composition for forming a resin layer, the ratio of the content of the filler (D) to the total content of all components other than the solvent (that is, the filler of the thermosetting resin film) (D) content), preferably 3 to 60% by mass, more preferably 3 to 55% by mass. With the content of the filler (D) in this range, when the thermosetting resin film before curing is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C becomes easy to adjust It is 500Pa‧s or more. When the thermosetting resin film is attached to the bumped surface of the semiconductor wafer and thermally cured, the shrinkage of the surface of the semiconductor wafer can be suppressed. In addition, at the top of the bump, the effect of suppressing the residue of the first protective film residue is further improved, and the adjustment of the above-described thermal expansion coefficient becomes easier.

[Coupling agent (E)]
The composition for forming a resin layer and the thermosetting resin film may contain a coupling agent (E). As the coupling agent (E), by using a functional group that can react with an inorganic compound or an organic compound, the adhesion and adhesion of the thermosetting resin film to the adherend can be improved. In addition, by using the coupling agent (E), the first protective film obtained by curing the thermosetting resin film does not impair heat resistance and can improve water resistance.

The coupling agent (E) is preferably a compound having a functional group that can react with a functional group possessed by the polymer component (A), thermosetting component (B), etc., and more preferably a silane coupling agent.
Preferred examples of the silane coupling agent include, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyl diethoxysilane, and 3-glycidyl. Oxypropyltriethoxysilane, 3-glycidoxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methylpropene Acyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethyl Amino)propylmethyl diethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane , 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl) tetrasulfide, methyltrimethoxysilane, methyl Triethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, imidazole silane, etc.

The coupling agent (E) contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When the coupling agent (E) is two or more types, these combinations and ratios can be arbitrarily selected.

When the coupling agent (E) is used, the content of the coupling agent (E) in the composition for forming a resin layer and the thermosetting resin film is different from that of the polymer component (A) and the thermosetting component (B) The total content is 100 parts by mass, 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.
When the content of the coupling agent (E) is more than the above lower limit, the dispersibility of the filler (D) to the resin is improved, the adhesion between the thermosetting resin film and the adherend is improved, etc., the coupling agent is used (E) The effect achieved is more significant. In addition, when the content of the coupling agent (E) is equal to or less than the above upper limit value, the occurrence of outgassing is further suppressed.

[Crosslinking agent (F)]
As the polymer component (A), when the acrylic resin and the like having functional groups such as vinyl groups, (meth)acryloyl groups, amine groups, hydroxyl groups, carboxyl groups, and isocyanate groups that can be bonded to other compounds are used, The composition for forming a resin layer and the thermosetting resin film may contain a crosslinking agent (F). The crosslinking agent (F) is a component for bonding and crosslinking the above functional groups in the polymer component (A) with other compounds, and by such crosslinking, the initial adhesion of the thermosetting resin film can be adjusted And cohesion.

Examples of the crosslinking agent (F) include organic polyvalent isocyanate compounds, polyvalent imine compounds, metal chelate crosslinkers (crosslinkers with metal chelate structure), and aziridine crosslinkers. Agent (crosslinking agent with aziridine group), etc.

Examples of the organic polyvalent isocyanate compound include, for example, aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, and alicyclic polyvalent isocyanate compounds (hereinafter, these compounds are sometimes collectively referred to as "aromatic polyvalent Isocyanate compounds, etc."); terpolymers, isocyanurates and adducts of the above-mentioned aromatic polyvalent isocyanate compounds, etc.; terminal isocyanate urethanes obtained by reaction of the above-mentioned aromatic polyvalent isocyanate compounds with polyol compounds Ethyl polymer, etc. The above-mentioned "adduct" means the above-mentioned aromatic polyvalent isocyanate compound, aliphatic polyvalent isocyanate compound or alicyclic polyvalent isocyanate compound and ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor Reaction products of low molecular weight active hydrogen-containing compounds such as sesame oil. Examples of the above-mentioned adducts include the following xylylene diisocyanate adducts of trimethylolpropane and the like. In addition, the so-called "terminal isocyanate urethane polymer" is as previously explained.

As the organic polyvalent isocyanate compound, more specifically, for example, 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 1,3-xylylene diisocyanate; 1,4- Xylylene diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene di Isocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; all or part of the hydroxyl groups in polyhydric alcohols such as trimethylolpropane , Add one or more than two kinds of toluene diisocyanate, hexamethylene diisocyanate and any one of the compounds of xylylene diisocyanate; diamine diisocyanate and so on.

Examples of the polyvalent imine compound include N,N′-diphenylmethane-4,4′-bis(1-aziridinecarboxamide) and trimethylolpropane-tri-β- Aziridine propionate, tetramethylolmethane-tri-β-aziridine propionate, N,N'-toluene-2,4-bis(1-aziridinecarboxamide) tris Ethyl melamine and so on.

When an organic polyvalent isocyanate compound is used as the crosslinking agent (F), it is preferred to use a polymer containing a hydroxyl group as the polymer component (A). When the cross-linking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, the cross-linking agent (F) and the polymer component (A) can be easily introduced into the thermosetting resin film through the reaction联结构。 Joint construction.

The crosslinking agent (F) contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When there are two or more crosslinking agents (F), these combinations and ratios can be arbitrarily selected.

When a crosslinking agent (F) is used, in the composition for forming a resin layer, the content of the crosslinking agent (F) relative to the content of the polymer component (A) is 100 parts by mass, preferably 0.01 to 20 parts by mass, It is more preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass. When the above-mentioned content of the cross-linking agent (F) is at least the above-mentioned lower limit, the effect achieved by using the cross-linking agent (F) becomes more remarkable. In addition, when the content of the crosslinking agent (F) is equal to or less than the above upper limit, the excessive use of the crosslinking agent (F) can be suppressed.

[Other ingredients]
The composition for forming a resin layer and the thermosetting resin film may contain the above-mentioned polymer component (A), thermosetting component (B), curing accelerator (C), and filler as long as the effect of the present invention is not impaired (D), other components than the coupling agent (E) and the crosslinking agent (F).
Examples of the other components mentioned above include energy ray-curable resins, photopolymerization initiators, colorants, and general-purpose additives. The above-mentioned general-purpose additives may be conventional ones, and can be arbitrarily selected according to the purpose, and are not particularly limited, but preferred ones include, for example, plasticizers, antistatic agents, antioxidants, colorants (dye, pigment) , Gettering agent, etc.

The other components contained in the composition for forming a resin layer and the thermosetting resin film may be only one kind or two or more kinds. When the above-mentioned other components are two or more types, these combinations and ratios can be arbitrarily selected.
The contents of the other components of the composition for forming a resin layer and the thermosetting resin film are not particularly limited, and may be appropriately selected according to the purpose.

The composition for forming a resin layer and the thermosetting resin film include a polymer component (A) and a thermosetting component (B), and a polyvinyl acetal as the polymer component (A), and a liquid The epoxy resin (B1) is preferred, and in addition to these components, those further containing a hardening accelerator (C) and a filler (D) are more preferred. Then, the filler (D) at this time preferably has the above-mentioned average particle diameter. By using such a composition for forming a resin layer and a thermosetting resin film, when the thermosetting resin film before curing is heated at 10°C/min, the minimum value of the shear viscosity at 90 to 130°C becomes It is easy to adjust to 500Pa‧s or more. When the thermosetting resin film is attached to the bumped surface of the semiconductor wafer to thermally cure it, the shrinkage of the surface of the semiconductor wafer can be suppressed. In addition, at the top of the bump, the effect of suppressing the residue of the first protective film becomes more enhanced.

The composition for forming a resin layer and the thermosetting resin film contain one or more kinds selected from polyvinyl formal, polyvinyl butyral, and acrylic resin as the polymer component (A), and a liquid One or more types of dicyclopentadiene-type epoxy resin and liquid bisphenol A-type epoxy resin are preferred as the epoxy resin (B1). In addition to these components, further selected from 2-phenyl- One or more types of 4-methylimidazole and 2-phenyl-4,5-dihydroxymethylimidazole are used as hardening accelerators (C), and one or more types selected from silica and alumina are used as fillers (D ) Is better.

[Solvent]
It is preferable that the composition for forming a resin layer further contains a solvent. The solvent-containing composition for forming a resin layer has good handleability.
The above solvent is not particularly limited, but preferred examples include hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, and isobutanol (also known as 2-methylpropane-1- Alcohol), alcohol such as 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides such as dimethylformamide and N-methylpyrrolidone (with Amide bond compound) etc.
The above-mentioned solvent contained in the composition for forming a resin layer may be only one kind, or two or more kinds. When the above-mentioned solvents are two or more types, these combinations and ratios can be arbitrarily selected.

The solvent contained in the composition for forming a resin layer is preferably methyl ethyl ketone or the like from the viewpoint that the components contained in the composition for forming a resin layer can be more uniformly mixed.

The content of the solvent in the composition for forming a resin layer is not particularly limited. For example, it may be appropriately selected according to the type of components other than the solvent.

<<Method for manufacturing composition for forming thermosetting resin film>>
The composition for thermosetting resin film formation, such as the composition for resin layer formation, can be obtained by mixing each component which comprises these.
When mixing each component, the order of addition is not particularly limited, and two or more components may be added simultaneously.
When a solvent is used, the solvent may be mixed with each formulation component other than the solvent, and these formulation components may be used after being diluted in advance, or each formulation component other than the solvent may not be diluted in advance, and the solvent may be mixed with these formulation components And use.
The method of mixing the components at the time of preparation is not particularly limited, and it can be appropriately selected from known methods such as a method of rotating and mixing a stirrer or a stirring blade, a method of mixing using a mixer, and a method of mixing by applying ultrasonic waves. can.
The temperature and time at the time of addition and mixing of each component are not particularly limited as long as they do not deteriorate each formulated component, and may be adjusted appropriately, but the temperature is preferably 15 to 30°C.

◎ First Support Sheet In the sheet 1 for forming the first protective film, as the first support sheet 101, a conventional person can be used. For example, the first support sheet 101 includes the first base material 11 and the buffer layer 13 formed on the first base material 11. In other words, the first protective film forming sheet 1 is formed by stacking in the thickness direction of the first base material 11, the buffer layer 13 and the thermosetting resin film 12 in this order.

◎ First base material The first base material is in the form of a sheet or a film, and its constituent materials include, for example, various resins.
Examples of the resins include polyethylenes such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE); polypropylene, polybutene, and polybutadiene Polyolefins other than polyethylene such as polymethylpentene and norbornene resin; ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymerization Vinyl copolymers (copolymers obtained using ethylene as a monomer); vinyl chloride resins such as polyvinyl chloride, vinyl chloride copolymers (using vinyl chloride) Resin obtained as a monomer); polystyrene; polycycloolefin; polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyisophthalate Polyesters such as ethylene formate, polyethylene-2,6-naphthalene dicarboxylate, fully aromatic polyesters having aromatic ring groups in all constituent units; copolymerization of two or more of the above polyesters Poly(meth)acrylate; Polyurethane; Polyurethane acrylate; Polyimide; Polyamide; Polycarbonate; Fluorine resin; Polyacetal; Modified polyphenylene ether; Polysulfide benzene; Polysulfone; Poly Ether ketone, etc.
In addition, examples of the resin include a polymer blend such as a mixture of the polyester and resins other than the above. The polymer blend of the above-mentioned polyester and resins other than it is preferably a smaller amount of resins other than polyester.
In addition, as the above-mentioned resin, for example, a cross-linked resin in which one or more of the above-mentioned resins exemplified above are cross-linked; and one or more of the above-mentioned resins exemplified above are used. Modified resins such as ionic polymers.

The resin constituting the first base material may be only one kind or two or more kinds. When the resin constituting the first base material is two or more types, these combinations and ratios can be arbitrarily selected.

The first substrate may be only one layer (single layer), or plural layers of more than two layers. When the first substrate is a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of the plurality of layers is not particularly limited.
Moreover, in this specification, not only the first substrate, the so-called "multiple layers may be the same or different from each other" means "may be all the layers are the same, or all the layers are different, or only a part of Same level". Furthermore, "the plural layers are different from each other" means that "at least one of the constituent materials and thickness of each layer is different from each other".

The thickness of the first substrate is preferably 5 to 1000 μm, more preferably 10 to 500 μm, further preferably 15 to 300 μm, and particularly preferably 20 to 150 μm.
Here, the "thickness of the first substrate" refers to the thickness of the entire first substrate, for example, the thickness of the first substrate composed of a plurality of layers refers to the thickness of all the layers constituting the first substrate Total thickness.

The first base material is preferably the one with high thickness accuracy, that is, the one where the variation in the thickness of any part is suppressed. Among the above-mentioned constituent materials, examples of materials that can be used to constitute such a first substrate with high thickness accuracy include, for example, polyethylene, polyolefins other than polyethylene, polyethylene terephthalate, and ethylene-acetic acid. Vinyl ester copolymer, etc.

In addition to the main constituent materials such as the above resins, the first base material may also contain conventional materials such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (also known as plasticizers). Of various additives.

The first substrate may be transparent or opaque, it may be colored according to the purpose, and other layers may be vapor-deposited.
When the thermosetting resin film is energy ray-curable, the first substrate is preferably one that can penetrate energy ray.

The first substrate can be manufactured by a conventional method. For example, the resin-containing first substrate can be manufactured by molding the resin composition containing the resin.

◎ Peeling film The peeling film mentioned above may be known in this field.
Examples of the above-mentioned peeling film include, for example, those on which at least one surface of a resin film such as polyethylene terephthalate is subjected to peeling treatment by silicone treatment or the like; at least one of the films The surface on the side becomes a peeling surface made of polyolefin or the like.
The thickness of the release film is preferably the same as the thickness of the first substrate.

◎Buffer layer The buffer layer 13 has a buffering effect on the force applied to the buffer layer 13 and the layer adjacent thereto. In this embodiment, the thermosetting resin film 12 is shown as a "layer adjacent to the buffer layer".

The buffer layer 13 is in the form of a sheet or a film, and preferably has energy beam curability. The energy ray-curable buffer layer 13 is cured by the energy ray, which makes it easier to peel from the thermosetting resin film 12 described below.

Examples of the constituent material of the buffer layer 13 include various adhesive resins. Examples of the adhesive resin include acrylic resins, urethane resins, rubber resins, silicone resins, epoxy resins, polyvinyl ether, and polycarbonate. Acrylic resin is preferred. When the buffer layer 13 is energy ray hardenable, as its constituent material, various components necessary for energy ray hardening can be cited.

Moreover, in the present invention, the so-called "adhesive resin" includes the concept of both adhesive resin and adhesive resin, for example, not only the resin itself is adhesive, but also includes additives and other A resin that exhibits adhesion by the combined use of components, or a resin that exhibits adhesion by the presence of triggers such as heat and water.

The buffer layer 13 may be only one layer (single layer), or plural layers of two or more layers. When the buffer layer 13 is 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 buffer layer 13 is preferably 30 to 500 μm.
Here, the "thickness of the buffer layer 13" refers to the thickness of the entire buffer layer 13, for example, the thickness of the buffer layer 13 composed of a plurality of layers refers to the total thickness of the layers constituting the entire buffer layer 13.

＜＜Adhesive resin composition＞＞
The buffer layer 13 can be formed using an adhesive resin composition containing an adhesive resin. For example, by applying an adhesive resin composition on the surface to be formed of the buffer layer 13 and drying it as necessary, the buffer layer 13 can be formed on the target site.

The application of the adhesive resin composition can be performed by a conventional method. For example, an air knife coater, a blade coater, a rod coater, a gravure coater, a roll coater, Roller coater, curtain coater, die coater, knife coater, screen coater, Mayer bar coater, stapling coater and other various coater methods.

The drying conditions of the adhesive resin composition are not particularly limited, but it is preferable to heat-dry the adhesive resin composition containing a solvent described below. For example, the adhesive resin composition containing a solvent is preferably dried at 70 to 130° C. for 10 seconds to 5 minutes.

When the buffer layer 13 is energy ray curable, the adhesive resin composition containing the energy ray curable adhesive, that is, the energy ray curable adhesive resin composition, for example, contains non-energy ray curable Adhesive resin composition (I-1a) (hereinafter, abbreviated as "adhesive resin (I-1a)") and an energy ray-curable compound (I-1); contained in non-energy ray-curable Adhesiveness of the energy-curable adhesive resin (I-2a) (hereinafter, abbreviated as "adhesive resin (I-2a)") in which the unsaturated resin is introduced into the side chain of the adhesive resin (1-1a) Resin composition (I-2); an adhesive resin composition (I-3) containing the above-mentioned adhesive resin (I-2a) and an energy ray-curable low molecular weight compound, etc.

As the adhesive resin composition, in addition to the energy ray-curable adhesive resin composition, a non-energy ray-curable adhesive resin composition can also be mentioned.
Examples of the non-energy ray-curable adhesive resin composition include, for example, acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, and polycarbonate The adhesive resin composition (I-4) containing a non-energy ray-curable adhesive resin (I-1a), such as an ester or an ester-based resin, is preferably an acrylic resin.

<<Method for producing adhesive resin composition>>
The above-mentioned adhesive resin composition such as the adhesive resin compositions (I-1) to (I-4) can be formed by combining the above-mentioned adhesive resin with components other than the above-mentioned adhesive resin as necessary Each component of the sexual resin composition is obtained by mixing.
When mixing each component, the order of addition is not particularly limited, and two or more components may be added simultaneously.
When a solvent is used, the solvent may be mixed with each formulation component other than the solvent, and the formulation component may be used after dilution in advance, or each formulation component other than the solvent may not be diluted in advance, and the solvent may be mixed with these formulation components. use.
The method of mixing the components at the time of preparation is not particularly limited, and it is appropriately selected from conventional methods such as a method of rotating and mixing a stirrer or a stirring wing, a method of mixing using a mixer, and a method of mixing by applying ultrasonic waves. can.
The temperature and time at the time of addition and mixing of the components are not particularly limited as long as they do not deteriorate the formulated components, and may be adjusted appropriately, but the temperature is preferably 15 to 30°C.

◇Manufacturing method of the first protective film forming sheet The first protective film forming sheet can be manufactured by layering sequentially so as to correspond to the positional relationship of the above layers. The formation method of each layer is as previously explained.

For example, a sheet for forming a first protective film formed by stacking a buffer layer and a thermosetting resin film in this order on the first base material in this thickness direction can be manufactured by the method shown below . That is, for the first base material, the buffer layer is laminated on the first base material by extrusion molding the adhesive resin composition for forming the buffer layer. In addition, by applying the composition for forming a thermosetting resin film on the peeling treatment surface of the peeling film, and drying it as necessary, the thermosetting resin film is laminated. Then, the thermosetting resin film on the release film is bonded to the buffer layer on the first substrate, whereby the buffer layer, the thermosetting resin film and the release film can be obtained on the first substrate in this order The layered sheet for forming the first protective film. The release film may be removed when the first protective film forming sheet is used.

The sheet for forming a first protective film provided with layers other than the above-mentioned layers can be appropriately added with the forming steps of the above-mentioned other layers in the above-mentioned manufacturing method so that the lamination position of the above-mentioned other layers becomes an appropriate position It is manufactured by either or both of the lamination steps.

For example, a sheet for forming a first protective film formed by stacking an adhesive layer, a buffer layer, and a thermosetting resin film in this order on the first base material in this thickness direction can be obtained as follows Method. That is, for the first base material, by co-extrusion molding the composition for forming an adhesive layer and the adhesive resin composition for forming a buffer layer, the adhesive layer and the buffer layer are formed on the first substrate Sequential stacking. Then, in the same manner as described above, a thermosetting resin film is additionally deposited on the release film. Next, the thermosetting resin film on this release film is bonded to the first substrate and the buffer layer on the adhesive layer, whereby the adhesive layer, the buffer layer, and the thermosetting property can be obtained on the first substrate The sheet for forming the first protective film formed by stacking the resin film and the release film in this order. The release film on the thermosetting resin film may be removed when the first protective film forming sheet is used.

◇How to use the first protective film forming sheet The first protective film forming sheet of the present invention can be used in the following manner, for example.
That is, first, the sheet for forming the first protective film is bonded to the bump forming surface of the semiconductor wafer by its thermosetting resin film. At this time, by bonding while heating the curable resin film, the thermosetting resin film is softened, so that the thermosetting resin film adheres to the bump forming surface.
Next, after grinding the surface opposite to the bump forming surface of the semiconductor wafer (that is, the back surface) as needed, a sheet for forming a protective film for protecting the back surface is attached to this back surface (in this specification) , Called "the second protective film forming sheet"). Examples of the second protective film-forming sheet include, for example, those provided with a second protective film-forming film that forms a second protective film for protecting the semiconductor wafer and the back surface of the semiconductor wafer by curing, or may be further Those who have wafer dicing sheets.

Next, of the first protective film forming sheet bonded to the bump forming surface of the semiconductor wafer, only the thermosetting resin film remains on the bump forming surface, and the other layers are peeled from the thermosetting resin film. Here, the “other peeled layer” refers to, for example, the first protective film forming sheet 1 shown in FIG. 1, the first base material 11 and the buffer layer 13.
Next, by curing the thermosetting resin film, a first protective film is formed on the bump forming surface of the semiconductor wafer.

In the following, it is possible to proceed until the manufacture of the semiconductor device by the same method as in the past. That is, the semiconductor wafer provided with the first protective film is diced to form a semiconductor wafer, and the semiconductor wafer provided with the first protective film is picked up. The second protective film forming film can be cured at an appropriate time according to its type to form the second protective film. The picked semiconductor wafer is flip-chip mounted on a wiring board, and finally constitutes a semiconductor device.

By using the first protective film forming sheet of the present invention, at the stage of bonding the sheet to the bump forming surface of the semiconductor wafer, at least the upper part of the bump protrudes through the thermosetting resin film, and The remaining of the thermosetting resin film on the upper part of the block is suppressed. As a result, at least the upper part of the bump penetrates the first protective film and protrudes. When a semiconductor wafer flip-chip provided with such a first protective film and bumps is mounted on a wiring board, the electrical connection between the semiconductor wafer and the wiring board becomes good.
Hereinafter, the process from the bonding of the first protective film forming sheet of the present invention to the bump forming surface of the semiconductor wafer to the formation of the first protective film will be described in detail with reference to the drawings.

FIG. 2 is a cross-sectional view illustrating an example of a method of using the first protective film forming sheet 1 shown in FIG. 1.
When using the first protective film-forming sheet 1, first, as shown in FIG. 2( a ), the first protective film-forming sheet 1 faces the bumps of the semiconductor wafer 9 with its thermosetting resin film 12. Arranged so as to form the surface 9a.

The height of the bump 91 is not particularly limited, but it is preferably 120-300 μm, more preferably 150-270 μm, and particularly preferably 180-240 μm. When the height of the bump 91 is more than the above lower limit, the function of the bump 91 can be further improved. In addition, when the height of the bump 91 is equal to or less than the above upper limit value, the effect of suppressing the remaining of the thermosetting resin film 12 on the upper portion of the bump 91 is further improved.
In addition, in this specification, the "height of the bump" refers to the height from the bump formation surface to the portion existing at the highest position among the bumps.

The width of the bump 91 is not particularly limited, but it is preferably 170 to 350 μm, more preferably 200 to 320 μm, and particularly preferably 230 to 290 μm. When the width of the bump 91 is equal to or greater than the above lower limit, the function of the bump 91 can be further improved. In addition, when the height of the bump 91 is equal to or less than the above upper limit value, the effect of suppressing the remaining of the thermosetting resin film 12 on the upper portion of the bump 91 is further improved.
Moreover, in this specification, the "bump width" means that when facing the bump forming surface and looking down at the bump from the vertical direction and looking up, the two different points on the bump surface are in a straight line The maximum value of the line segment obtained by joining.

The distance between adjacent bumps 91 is not particularly limited, but it is preferably 250-800 μm, more preferably 300-600 μm, and particularly preferably 350-500 μm. By the distance being above the lower limit, the function of the bump 91 can be further improved. In addition, when the distance is equal to or less than the upper limit value, the effect of suppressing the remaining of the thermosetting resin film 12 on the upper portion of the bump 91 is further improved.
In addition, in this specification, the "distance between adjacent bumps" refers to the minimum value of the distance between the surfaces of adjacent bumps.

Next, the thermosetting resin film 12 is brought into contact with the bump 91 on the semiconductor wafer 9, and the first protective film forming sheet 1 is pressed onto the semiconductor wafer 9. In this way, the first surface 12 a of the thermosetting resin film 12 is sequentially pressed against the surface 91 a of the bump 91 and the bump forming surface 9 a of the semiconductor wafer 9. At this time, by heating the thermosetting resin film 12, the thermosetting resin film 12 is softened, and diffuses between the bumps 91 so as to cover the bumps 91, and adheres to the bump forming surface 9 a while covering The surface 91a of the bump 91, particularly the surface 91a in the vicinity of the bump forming surface 9a, is embedded in the bump 91.
As described above, as shown in FIG. 2( b ), the thermosetting resin film 12 of the first protective film forming sheet 1 is bonded to the bump forming surface 9 a of the semiconductor wafer 9.

As described above, as a method of pressing the first protective film-forming sheet 1 on the semiconductor wafer 9, a known method in which various sheets are pressed on the object and attached can be applied, and examples include, for example, The method of using a lamination roll, etc.

The heating temperature of the sheet 1 for forming the first protective film when it is pressed against the semiconductor wafer 9 may be a temperature at which the curing of the thermosetting resin film 12 does not proceed at all or does not proceed excessively. ~100℃ is better, 85~95℃ is better.

The pressure when the first protective film forming sheet 1 is pressed against the semiconductor wafer 9 is not particularly limited, but it is preferably 0.1 to 1.5 MPa, and more preferably 0.3 to 1 MPa.

As described above, when the first protective film forming sheet 1 is pressed against the semiconductor wafer 9, the thermosetting resin film 12 and the buffer layer 13 in the first protective film forming sheet 1 are applied from the bump 91 At the initial stage, the first surface 12a of the thermosetting resin film 12 and the first surface 13a of the buffer layer 13 are deformed into a concave shape. Then, cracks occur on the thermosetting resin film 12 which is continuously subjected to the pressure applied from the bump 91. Finally, when the first surface 12 a of the thermosetting resin film 12 is pressed against the bump forming surface 9 a of the semiconductor wafer 9, the upper portion 910 of the bump 91 is in a state of protruding through the thermosetting resin film 12. Moreover, in this final stage, generally, the upper portion 910 of the bump 91 does not penetrate the buffer layer 13. This is because the buffer layer 13 has a buffer effect against the pressure applied from the bump 91.

As shown in FIG. 2( b ), when the first protective film forming sheet 1 is attached to the bump forming surface 9 a of the semiconductor wafer 9, on the upper portion 910 of the bump 91, the thermosetting resin film 12 is completely No or almost no residue. In addition, in this specification, "there is almost no thermosetting resin film remaining on the top of the bump", unless otherwise specified, it means that although there is a little thermosetting resin film remaining on the top of the bump, however, The remaining amount is the degree of electrical connection between the semiconductor wafer and the wiring substrate when the semiconductor wafer with these bumps is flip-chip mounted on the wiring substrate.

In this way, the upper portion 910 of the bump 91 is designed to suppress the remaining of the thermosetting resin film 12 in such a manner that when the thermosetting resin film 12 is deformed by the pressure applied from the bump 91 The thermosetting resin film 12 is particularly susceptible to cracking.

After the first protective film forming sheet 1 is attached to the bump forming surface 9a of the semiconductor wafer 9, as necessary, it is further performed on the surface (rear surface) 9b opposite to the bump forming surface 9a of the semiconductor wafer 9 After grinding, the second protective film forming sheet (not shown) is attached to the back surface 9b.
Next, as shown in FIG. 2( c ), the first base material 11 and the buffer layer 13 are peeled from the thermosetting resin film 12.
Next, by curing the thermosetting resin film 12, as shown in FIG. 2(d), the first protective film 12' is formed on the bump forming surface 9a.

When the thermosetting resin film 12 of the present invention and the sheet 1 for forming the first protective film are provided, and the first protective film 12' is formed on the bump forming surface 9a, the thermosetting property before thermosetting When the resin film 12 is heated at 10°C/min, the minimum value of the shear viscosity at 90°C to 130°C is 500 Pa‧s or more, as shown in Fig. 3(c) and Fig. 3(d) There is a doubt that the defects exposed on the exposed surface 9ao of the semiconductor wafer are caused by shrinkage.

An aspect of the present invention is a composition for forming a resin layer, which contains polyvinyl butyral (having structural units represented by the above formulas (i)-1, (i)-2, and (i)-3, content : 5 to 85% by mass, more preferably 5 to 50% by mass, and still more preferably 5 to 20% by mass relative to the total mass of the solid content of the composition for forming a resin layer) as a polymer component (A); Contains epoxy resin (B1) (liquid bisphenol A epoxy resin, epoxy equivalent 404 to 412 g/eq, content: 20 to 40% by mass relative to the total mass of the solid content of the resin layer forming composition , More preferably 25 to 35% by mass), thermosetting agent (B2) (phenolic phenol resin, content: relative to the total mass of the solid content of the resin layer forming composition, 10 to 20% by mass, more preferably 13 to 17% by mass) as a thermosetting component (B); containing 2-phenyl-4,5-dimethylolimidazole (content: relative to the total mass of the solid content of the resin layer forming composition, 0.05 ~2% by mass, more preferably 0.1~1% by mass) as a hardening accelerator (C); containing epoxy-modified spherical silica (average particle diameter 0.05 μm, content: relative to the composition for forming a resin layer The total mass of the solid content is 3 to 60% by mass, more preferably 3 to 55% by mass, and even more preferably 5 to 10% by mass) as the filler (D), (however, the total content of each component, It does not exceed 100% by mass relative to the total mass of the solid content of the composition for forming a resin layer.
Another aspect of the present invention is a composition for forming a resin layer, which contains polyvinyl butyral (having structural units represented by the above formulas (i)-1, (i)-2, and (i)-3, Content: 5 to 85% by mass, more preferably 5 to 50% by mass, further more preferably 5 to 20% by mass relative to the total mass of the solid content of the composition for forming a resin layer) as a polymer component (A) ; Contains epoxy resin (B1) (dicyclopentadiene type epoxy resin, epoxy equivalent 254~264g/eq, content: relative to the total mass of the solid content of the resin layer forming composition, is 10~30 mass %, more preferably 15-25% by mass), thermosetting agent (B2) (phenolic phenol resin, content: 10-20% by mass relative to the total mass of the solid content of the resin layer forming composition, more preferably 13 to 17% by mass) as a thermosetting component (B); containing 2-phenyl-4,5-dimethylolimidazole (content: relative to the total mass of the solid content of the composition for forming a resin layer, is 0.05~2% by mass, more preferably 0.1~1% by mass) as a hardening accelerator (C); contains spherical silica modified with epoxy groups (average particle diameter 0.05 μm, content: relative to the combination for resin layer formation The total mass of the solid content of the substance is preferably 3 to 60% by mass, more preferably 3 to 55% by mass, and even more preferably 5 to 10% by mass) as the filler (D), (however, the content of each component The total of does not exceed 100% by mass relative to the total mass of the solid content of the composition for forming a resin layer.
Still another aspect of the present invention is a composition for forming a resin layer, which contains polyvinyl butyral (having structural units represented by the above formulas (i)-1, (i)-2, and (i)-3, Content: 5 to 85% by mass, more preferably 5 to 50% by mass, further more preferably 5 to 20% by mass relative to the total mass of the solid content of the composition for forming a resin layer) as a polymer component (A) ; Contains epoxy resin (B1) (liquid bisphenol A epoxy resin (epoxy equivalent 404~412g/eq, content: relative to the total mass of the solid content of the resin layer forming composition, is 20~40 mass %, more preferably 25 to 35% by mass) and dicyclopentadiene type epoxy resin (epoxy equivalent 254 to 264g/eq, content: relative to the total mass of the solid content of the resin layer forming composition, 10 ~30% by mass, preferably 15-25% by mass)), thermosetting agent (B2) (phenolic phenol resin, content: relative to the total mass of the solid content of the resin layer forming composition, 10-20% %, more preferably 13 to 17% by mass) as a thermosetting component (B); containing 2-phenyl-4,5-dimethylolimidazole (content: relative to the solid content of the resin layer forming composition) The total mass is 0.05~2% by mass, more preferably 0.1~1% by mass) as a hardening accelerator (C); contains spherical silica modified with epoxy groups (average particle diameter 0.05μm, content: relative to resin The total mass of the solid content of the layer-forming composition is 3 to 60% by mass, more preferably 3 to 55% by mass, and even more preferably 5 to 10% by mass) as a filler (D), (however, each component The total of the content of R, does not exceed 100% by mass relative to the total mass of the solid content of the composition for forming a resin layer.

An aspect of the present invention is a thermosetting resin film (thickness: 1 to 100 μm, more preferably 5 to 75 μm, and particularly preferably 5 to 50 μm) formed from the composition for forming a resin layer.
Another aspect of the present invention includes a sheet for forming a first protective film provided with the above thermosetting resin film on the surface of one side of the first support sheet.
[Example]

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

The components used in the production of the thermosetting resin film forming composition are shown below.
‧Polymer composition (A)
Polymer component (A)-1: Polyvinyl butyral having structural units represented by the following formulas (i)-1, (i)-2 and (i)-3 (manufactured by Sekisui Chemical Industry Co., Ltd. "S-LEC" (Registered trademark) B BL-10", weight average molecular weight 25,000, glass transition temperature 59°C. In the formula, l ₁ is 68 to 74 mol%, m ₁ is 1 to 3 mol%, and n ₁ is about 28 mol%).

Polymer component (A)-2: Polyvinyl butyral having structural units represented by the following formulas (i)-1, (i)-2, and (i)-3 ("S-LEC" manufactured by Sekisui Chemical Co., Ltd. (Registered trademark) B BL-1", weight average molecular weight 30,000, glass transition temperature 66°C. In the formula, l ₁ is 60 to 66 mol%, m ₁ is 1 to 3 mol%, and n ₁ is about 36 mol%)

Polymer component (A)-3: Polyvinyl butyral having structural units represented by the following formulas (i)-1, (i)-2, and (i)-3 ("S-LEC" manufactured by Sekisui Chemical Industry Co., Ltd. (Registered trademark) SV-02", weight average molecular weight 50,000, glass transition temperature 59°C. In the formula, n ₁ is about 22 mol%)

Polymer component (A)-4: Polyvinyl butyral having structural units represented by the following formulas (i)-1, (i)-2 and (i)-3 (manufactured by Sekisui Chemical Industry Co., Ltd. "S-LEC" (Registered trademark) B BM-S", weight average molecular weight 66,000, glass transition temperature 60°C. In the formula, l ₁ is 70 to 76 mol%, m ₁ is 4 to 6 mol%, and n ₁ is about 22 mol%)

[Chem 2]

In the formula, l ₁ , m ₁ and n ₁ are the content ratio (mol%) of the constituent units.

‧Thermosetting component (B)
Epoxy resin (B1)-1: Liquid bisphenol A epoxy resin ("EPICLON (registered trademark) EXA-4850-1000" manufactured by DIC Corporation, epoxy equivalent 404~412g/eq)
Epoxy resin (B1)-2: Dicyclopentadiene type epoxy resin ("EPICLON (registered trademark) HP-7200" manufactured by DIC Corporation, epoxy equivalent 254~264g/eq)
Thermosetting agent (B2)-1: phenolic phenol resin ("Shonol (registered trademark) BRG-556" manufactured by Showa Denko Corporation)

‧Hardening accelerator (C)
Hardening accelerator (C)-1: 2-phenyl-4,5-dimethylolimidazole ("CUREZOL (registered trademark) 2PHZ" manufactured by Shikoku Chemical Industry Co., Ltd.)
‧Filling material (D)
Filler (D)-1: spherical silica modified with epoxy groups (Admatechs Inc. "ADMANANO (registered trademark) YA050C-MKK", average particle diameter 0.05 μm)

[Example 1]
<Manufacture of thermosetting resin film>
(Manufacture of thermosetting resin film forming composition)
(A)-1, epoxy resin (B1)-1, epoxy resin (B1)-2, thermosetting agent (B2)-1, curing accelerator (C)-1 and filler (D)-1 The ratio of these contents was dissolved or dispersed in methyl ethyl ketone so as to be the value shown in Table 1, and stirred at 23°C, whereby a composition for forming a resin layer having a solid content concentration of 55% by mass was obtained as The composition for thermosetting resin film formation. In addition, the description of "-" in the component-containing column in Table 1 means that the composition for forming a thermosetting resin film does not contain this component.

(Manufacture of thermosetting resin film)
For the peeling film (“SP-PET381031” manufactured by LINTEC Corporation, thickness 38 μm) on one side of the polyethylene terephthalate film which was peeled off by silicone treatment on one side, the above peeling treated surface was coated The thermosetting resin film forming composition obtained above was heated and dried at 120° C. for 2 minutes to obtain a thermosetting resin film with a thickness of 30 μm.
The thickness of the thermosetting resin film was measured using a contact thickness gauge (manufactured by Teclock, product name "PG-02").

<Evaluation of minimum shear viscosity of thermosetting resin film>
Next, by laminating a plurality of the thermosetting resin films, a thermosetting resin film having a thickness of 500 μm is formed. From this, a cylindrical sample for evaluation having a diameter of 25 mm and a thickness of 500 μm was prepared, and this sample was set in a shear viscosity measuring device. At this time, the sample is placed on the installation place of the measurement device, and pushed from the top of the sample to the measurement jig, whereby the sample is fixedly installed in the installation place.
The shear viscosity from room temperature to 150°C was measured every 1 second under the measurement conditions of frequency: 1 Hz, heating rate ‧10°C/min. The measurement results are shown in Fig. 4. Then, the minimum value of the shear viscosity at 90℃~130℃ is obtained.

<Manufacture of a sheet for forming the first protective film>
Next, using an adhesive tape ("E-8510HR" manufactured by LINTEC) as the first support sheet, the object layer to which the adhesive tape is attached is bonded to the thermosetting resin film on the above-mentioned peeling film. The first support sheet, the thermosetting resin film, and the release film are obtained in this order, and a sheet for forming a first protective film having a structure as shown in FIG.

<Evaluation of shrinkage>
On the first protective film forming sheet obtained above, the peeling film was removed, and the surface (exposed surface) of the thermosetting resin film exposed by this was pressed against the bump forming surface of the 8-inch φ bump wafer The first protective film forming sheet is attached to the bump forming surface of the semiconductor wafer. At this time, the first protective film forming sheet was attached by using an attaching device (roller laminator, "RAD-3510 F/12" manufactured by LINTEC), with a heating table temperature of 90°C and an attaching speed 2 mm/sec, with a pressure of 0.5 MPa, while heating the thermosetting resin film. As an 8-inch φ bump wafer, a bump height of 210 μm, a bump width of 250 μm, a distance between adjacent bumps of 400 μm, and a 0.4 mm pich BGA semiconductor wafer (WLP TEG M2 manufactured by Walts) are used. .
In the above manner, a laminated structure (1) can be obtained in which the first protective film forming sheet is attached to the bump formation surface of the semiconductor wafer.

After that, it was irradiated with ultraviolet rays, and the adhesive tape was peeled off (made by LINTEC, RAD-2700). The wafer with the thermosetting resin film attached was put in a pressure oven (RAD-9100 made by LINTEC) at a temperature : 130 ℃, time: 2h, furnace pressure: 0.5MPa heating conditions for heat treatment, so that the thermosetting resin film is thermally cured.
After thermal hardening, the bump surface was scanned with an electron microscope. Samples with visible spots on the surface of the semiconductor wafer were evaluated as having shrinkage. Samples with no visible spots on the surface of the semiconductor wafer were retracted. The evaluation is "none".

[Examples 2-8, Comparative Example 1]
<Manufacture and evaluation of thermosetting resin film>
In the production of the thermosetting resin film-forming composition, either or both of the types and content ratios of the components are as shown in Tables 1 and 2, except for the same method as in Example 1. , Manufacturing a sheet for forming a thermosetting resin film and a first protective film, and evaluating the minimum shear viscosity and shrinkage of the thermosetting resin film. The results are shown in Table 1, Table 2 and Figure 4.

[Table 1]

[Table 2]

From the results shown in Table 1 and Table 2, it can be seen that the minimum value of the shear viscosity at 90°C to 130°C is 500 Pa‧s or more, and the thermosetting resin films of Examples 1 to 8 did not occur on the semiconductor wafer The defects exposed on the exposed surface 9ao did not shrink.
[Industry availability]

The present invention can be used in a flip-chip mounting method, and can be used in the manufacture of semiconductor wafers having bumps at connection pads.

1‧‧‧ First protective film forming sheet

11‧‧‧The first substrate

11a‧‧‧First side of the first substrate

12‧‧‧thermosetting resin film

12a‧‧‧The first side of thermosetting resin film

12’‧‧‧First protective film

13‧‧‧buffer layer

13a‧‧‧The first side of the buffer layer

101‧‧‧ First support sheet

101a‧‧‧surface

9‧‧‧ semiconductor wafer

9a‧‧‧Surface bump formation surface of semiconductor wafer

9ao‧‧‧Exposed surface of semiconductor wafer

91‧‧‧Bump

91a‧‧‧Bump surface

910‧‧‧The upper part of the convex bump

1 is a cross-sectional view illustrating an embodiment of a sheet for forming a thermosetting resin film and a first protective film of the present invention.

2 is a cross-sectional view illustrating an example of a method of using the thermosetting resin film and the first protective film forming sheet shown in FIG. 1.

3 is a cross-sectional view illustrating an example of a method of using the thermosetting resin film and the first protective film forming sheet of the comparative example.

4 is a graph showing the measurement results of the shear viscosity of the thermosetting resin films of Examples and Comparative Examples.

Claims (4)

A thermosetting resin film is a thermosetting resin film attached to a surface of a semiconductor wafer having bumps, which is used to form a first protective film on the surface by thermally curing it. When the above thermosetting resin film is heated at 10°C/min, the minimum shear viscosity at 90°C to 130°C is 500 Pa‧s or more. The thermosetting resin film as described in item 1 of the patent application scope contains a polymer component (A) and a thermosetting component (B). The thermosetting resin film as described in item 1 or item 2 of the patent application scope contains polyvinyl acetal. A sheet for forming a first protective film includes a thermosetting resin film as described in any one of claims 1 to 3 on the surface of one side of the first support sheet.