JP2023142901A - Adhesive film for semiconductor, integration-type film for dicing and die bonding, and method for manufacturing semiconductor device - Google Patents

Abstract

To provide an adhesive film for semiconductor, which enables the suppression of bleeding in burying a semiconductor chip or wire, and which has a satisfactory fracture strength even after being cured.SOLUTION: Disclosed is an adhesive film for semiconductor, which comprises a thermosetting component, an elastomer, a first inorganic filler and a second inorganic filler. In the adhesive film for semiconductor, the first inorganic filler is 300-1000 nm in average particle size, the second inorganic filler has an average particle size which is 0.05-0.70 times that of the first inorganic filler, and the total content of the first inorganic filler and the second inorganic filler is 30-60 mass% to a total mass of the adhesive film for semiconductor.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to an adhesive film for semiconductors, an integrated dicing/die bonding film, and a method for manufacturing a semiconductor device.

Stacked MCPs (Multi Chip Packages), which have increased capacity by stacking semiconductor chips in multiple stages, have become popular. Examples of stacked MCPs include wire-embedded and chip-embedded semiconductor packages. The structure of a semiconductor package in which wires are embedded with an adhesive film is sometimes referred to as FOW (Film Over Wire). A structure of a semiconductor package in which a semiconductor chip is embedded with an adhesive film is sometimes referred to as FOD (Film Over Die). An example of a semiconductor package employing FOD is one that has a controller chip placed at the bottom and an adhesive film embedding the controller chip (see Patent Document 1). In the production of semiconductor packages with FOD or FOW structures, it is required that the semiconductor chips or wires be fully embedded by the adhesive film.

Japanese Patent Application Publication No. 2014-175459

However, the conventional adhesive film has a high flowability from the viewpoint of improving the embedding property of the controller chip, and the resin tends to bleed from the edge of the chip, so there is still room for improvement. In addition, from the viewpoint of reliability of semiconductor packages, the properties of the adhesive film after curing are required to be able to suppress defects such as the occurrence of cracks. In order to prevent such problems, the adhesive film after curing needs to have sufficient breaking strength.

Therefore, the main object of the present disclosure is to provide an adhesive film for semiconductors that can suppress bleeding when embedding a semiconductor chip or wire and has sufficient breaking strength after curing.

According to the studies conducted by the present inventors, by combining certain inorganic fillers, it is possible to suppress bleeding when embedding semiconductor chips or wires, and furthermore, it is possible to improve the breaking strength after curing. They have found that it is possible and have completed the invention of the present disclosure.

One aspect of the present disclosure relates to adhesive films for semiconductors. The adhesive film for semiconductors (hereinafter sometimes simply referred to as "adhesive film") contains a thermosetting component, an elastomer, a first inorganic filler, and a second inorganic filler. The first inorganic filler and the second inorganic filler satisfy all of the following conditions.
- The average particle size of the first inorganic filler is 300 to 1000 nm.
- The average particle size of the second inorganic filler is 0.05 to 0.70 times the average particle size of the first inorganic filler.
- The total content of the first inorganic filler and the second inorganic filler is 30 to 60% by mass based on the total amount of the adhesive film.

One embodiment of the adhesive film may have a thickness of 60-150 μm. In this case, the adhesive film may be an FOD adhesive film used to adhere a semiconductor chip to a substrate while embedding another semiconductor chip.

Other embodiments of the adhesive film may have a thickness of 25-80 μm. In this case, the adhesive film may be an FOW adhesive film used for bonding to another semiconductor chip while embedding part or all of the wires connected to the other semiconductor chip.

The content of elastomer may be 15 to 35% by weight, based on the total amount of the adhesive film.

The content of the thermosetting component may be 10 to 40% by mass based on the total amount of the adhesive film.

The thermosetting component may include a liquid epoxy resin that is liquid at 30°C. At this time, the content of the liquid epoxy resin may be 5 to 20% by mass based on the total amount of the adhesive film.

Another aspect of the present disclosure relates to an integrated dicing and die bonding film. The dicing/die bonding integrated film includes a dicing film and the above adhesive film provided on the dicing film.

Another aspect of the present disclosure relates to a method of manufacturing a semiconductor device. One embodiment of the method for manufacturing a semiconductor device includes bonding a second semiconductor chip to a substrate on which a first semiconductor chip is mounted using the adhesive film described above. In this case, the first semiconductor chip is embedded with an adhesive film.

Another aspect of the method for manufacturing a semiconductor device includes bonding a second semiconductor chip to the first semiconductor chip using the adhesive film described above. In this case, part or all of the wire is embedded with an adhesive film.

In one embodiment or another embodiment of the method for manufacturing a semiconductor device, the first semiconductor chip may be a controller chip.

According to the present disclosure, there is provided an adhesive film for semiconductors that can suppress bleeding when embedding a semiconductor chip or wire and has sufficient breaking strength after curing. Further, according to the present disclosure, a dicing/die bonding integrated film including such a semiconductor adhesive film is provided. Furthermore, according to the present disclosure, a method for manufacturing a semiconductor device using these adhesive films for semiconductors or integrated dicing and die bonding films is provided.

FIG. 1 is a schematic cross-sectional view showing one embodiment of an adhesive film. FIG. 2 is a schematic cross-sectional view showing one embodiment of a laminate including an adhesive film. FIG. 3 is a schematic cross-sectional view showing one embodiment of a laminate including an adhesive film. FIG. 4 is a schematic cross-sectional view showing one embodiment of a semiconductor device. FIG. 5 is a process diagram showing an embodiment of a method for manufacturing a semiconductor device. FIG. 6 is a process diagram showing one embodiment of a method for manufacturing a semiconductor device. FIG. 7 is a process diagram showing an embodiment of a method for manufacturing a semiconductor device. FIG. 8 is a process diagram showing an embodiment of a method for manufacturing a semiconductor device. FIG. 9 is a process diagram showing an embodiment of a method for manufacturing a semiconductor device. FIG. 10 is a schematic cross-sectional view showing another embodiment of the semiconductor device. FIG. 11 is a schematic cross-sectional view showing another embodiment of the semiconductor device.

This disclosure is not limited to the following examples. In the examples below, the components (including steps, etc.) are not essential unless explicitly stated. The sizes of the components in each figure are conceptual, and the relative size relationships between the components are not limited to those shown in each figure. The numerical values exemplified below and their ranges also do not limit the present disclosure.

In this specification, a numerical range indicated using "-" indicates a range that includes the numerical values written before and after "-" as the minimum and maximum values, respectively. In the numerical ranges described step by step in this specification, the upper limit value or lower limit value described in one numerical range may be replaced with the upper limit value or lower limit value of another numerical range described step by step. good. In the numerical ranges described in this specification, the upper limit or lower limit of the numerical range may be replaced with the value shown in the Examples.

As used herein, (meth)acrylate means acrylate or the corresponding methacrylate. The same applies to other similar expressions such as (meth)acrylic acid ester, (meth)acryloyl group, and (meth)acrylic copolymer.

The materials exemplified below may be used alone or in combination of two or more, unless otherwise specified. When a plurality of substances corresponding to each component are present in the composition, the content of each component in the composition means the total amount of the plurality of substances present in the composition, unless otherwise specified.

[Adhesive film for semiconductors (adhesive film)]
FIG. 1 is a schematic cross-sectional view showing one embodiment of an adhesive film. The adhesive film 10 shown in FIG. It contains one inorganic filler (hereinafter sometimes referred to as "component (C1)") and a second inorganic filler (hereinafter sometimes referred to as "component (C2)"). In addition to components (A), (B), (C1), and (C2), the adhesive film 10 contains a curing accelerator (hereinafter sometimes referred to as "component (D)"), and a coupling agent. (hereinafter sometimes referred to as "component (E)"), other components, etc. The adhesive film 10 may be a film formed from a thermosetting adhesive containing components (A), (B), (C1), (C2), and the like. The adhesive film 10 may be in a semi-cured (B stage) state. The adhesive film 10 may be in a cured (C-stage) state after the curing process.

(A) Component: Thermosetting component (A) Component may contain (A1) a thermosetting resin, which is a compound having a functional group that forms a crosslinked structure through a thermosetting reaction, and may contain a thermosetting resin. It may further contain a reactive curing agent (A2). From the viewpoint of adhesive properties, the thermosetting resin may contain an epoxy resin, which is a compound having an epoxy group. In that case, the curing agent may contain a phenolic resin, which is a compound having a phenolic hydroxyl group.

Epoxy resins used as thermosetting resins include, for example, bisphenol A epoxy resin; bisphenol F epoxy resin; bisphenol S epoxy resin; phenol novolac epoxy resin; cresol novolac epoxy resin; bisphenol A novolac epoxy resin. ; Bisphenol F novolak type epoxy resin; Stilbene type epoxy resin; Triazine skeleton-containing epoxy resin; Fluorene skeleton-containing epoxy resin; Triphenolmethane type epoxy resin; Biphenyl type epoxy resin; Xylylene type epoxy resin; Biphenylaralkyl type epoxy resin; Naphthalene type Epoxy resins include diglycidyl ether compounds of polyfunctional phenols and polycyclic aromatics such as anthracene. These may be used alone or in combination of two or more. Among these, the epoxy resin may include a cresol novolac type epoxy resin, a bisphenol F type epoxy resin, a bisphenol A type epoxy resin, or a combination thereof from the viewpoint of film tackiness, flexibility, etc.

The epoxy resin may include a liquid epoxy resin that is liquid at 30°C (an epoxy resin whose softening point is 40°C or lower). That is, the epoxy resin may be a combination of a liquid epoxy resin and a solid epoxy resin that is solid at 30°C (an epoxy resin whose softening point exceeds 40°C). In this specification, the softening point refers to a value measured by the ring and ball method in accordance with JIS K7234. The content of the liquid epoxy resin may be 3 to 20% by mass based on the total amount of the adhesive film. When the thermosetting resin contains a liquid epoxy resin, the flexibility of the adhesive film tends to improve. Further, by combining a liquid epoxy resin and a solid epoxy resin, the embeddability of semiconductor chips and wires tends to be excellent.

Commercially available liquid epoxy resins include, for example, EXA-830CRP (trade name, manufactured by DIC Corporation, liquid at 30°C), YDF-8170C (trade name, manufactured by Nippon Steel Chemical & Materials Co., Ltd., liquid at 30°C). , EP-4088S (trade name, manufactured by ADEKA Co., Ltd., liquid at 30°C), etc.

The epoxy equivalent of the epoxy resin is not particularly limited, but may be 90 to 300 g/eq or 110 to 290 g/eq. When the epoxy equivalent of the epoxy resin is within such a range, it tends to maintain the bulk strength of the adhesive film while ensuring fluidity of the thermosetting adhesive when forming the adhesive film.

Examples of the phenolic resin used as a curing agent include phenols such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol, and/or naphthols such as α-naphthol, β-naphthol, and dihydroxynaphthalene. and a compound having an aldehyde group such as formaldehyde under an acidic catalyst to condense or co-condense the novolac type phenol resin, allylated bisphenol A, allylated bisphenol F, allylated naphthalene diol, phenol novolak, phenol such as phenol. and/or naphthols and dimethoxyparaxylene or bis(methoxymethyl)biphenyl, and naphthol aralkyl resins. These may be used alone or in combination of two or more. The phenolic resin may include a phenylaralkyl type phenolic resin, a phenolic novolac resin, or a combination thereof.

The hydroxyl equivalent of the phenol resin may be 70 g/eq or more, or 70 to 300 g/eq. When the hydroxyl equivalent of the phenol resin is 70 g/eq or more, the storage modulus of the adhesive film tends to increase further. When the hydroxyl equivalent of the phenol resin is 300 g/eq or less, foaming and outgas generation can be further suppressed.

Commercially available phenolic resins include, for example, PSM-4326 (trade name, manufactured by Gunei Chemical Co., Ltd., softening point: 120°C), J-DPP-140 (trade name, manufactured by JFE Chemical Co., Ltd., softening point: 140℃), GPH-103 (trade name, manufactured by Nippon Kayaku Co., Ltd., softening point: 99-106℃), MEH-7800M (trade name, manufactured by Meiwa Kasei Co., Ltd., softening point: 80℃), J-DPP -85 (trade name, manufactured by JFE Chemical Co., Ltd., softening point: 85°C), MEH-5100-5S (trade name, manufactured by Meiwa Kasei Co., Ltd., softening point: 65°C), and the like.

When the thermosetting resin contains an epoxy resin and the curing agent contains a phenolic resin, the ratio of the epoxy equivalent of the epoxy resin to the hydroxyl equivalent of the phenol resin (epoxy equivalent: hydroxyl equivalent) is 0. 30/0.70 to 0.70/0.30, 0.35/0.65 to 0.65/0.35, 0.40/0.60 to 0.60/0.40, or 0.45 /0.55 to 0.55/0.45. When the ratio is 0.30/0.70 or more, more sufficient curability tends to be obtained. When the ratio is 0.70/0.30 or less, the viscosity can be prevented from becoming too high, and more sufficient fluidity can be obtained.

The softening point of the curing agent may be 50-200°C or 60-150°C. A curing agent having a softening point of 200° C. or lower tends to have good compatibility with a thermosetting resin.

The content of component (A) (total content of thermosetting resin and curing agent) may be 10 to 40% by mass based on the total amount of the adhesive film. When the content of component (A) is 10% by mass or more based on the total amount of the adhesive film, the breaking strength of the adhesive film after curing tends to be further improved, and when it is 40% by mass or less, the semiconductor chip Alternatively, it tends to be possible to further suppress bleeding when embedding the wire. The content of component (A) (total content of thermosetting resin and curing agent) may be 15% by mass or more, 20% by mass or more, or 25% by mass or more based on the total amount of the adhesive film. , 38% by weight or less, 35% by weight or less, or 32% by weight or less.

(B) Component: Elastomer Examples of the (B) component include acrylic resins, polyester resins, polyamide resins, polyimide resins, silicone resins, butadiene resins; modified products of these resins, and the like. These may be used alone or in combination of two or more. Among these, component (B) is derived from (meth)acrylic acid ester because it has less ionic impurities and has better heat resistance, makes it easier to ensure connection reliability of semiconductor devices, and has better fluidity. It may be an acrylic resin (acrylic rubber) having a structural unit as a main component. The content of the structural unit derived from the (meth)acrylic acid ester in component (B) may be, for example, 70% by mass or more, 80% by mass or more, or 90% by mass or more, based on the total amount of the structural units. The acrylic resin (acrylic rubber) may contain a structural unit derived from a (meth)acrylic acid ester having a crosslinkable functional group such as an epoxy group, an alcoholic or phenolic hydroxyl group, or a carboxyl group.

The glass transition temperature (Tg) of component (B) may be -50 to 50°C or -30 to 30°C. When the Tg of component (B) is -50°C or higher, it tends to be possible to prevent the adhesive film from becoming too flexible. This makes it easier to cut the adhesive film during wafer dicing, making it possible to prevent the occurrence of burrs. When the Tg of component (B) is 50° C. or lower, it tends to be possible to suppress a decrease in flexibility of the adhesive film. This tends to make it easier to fill in voids sufficiently when attaching the adhesive film to a semiconductor wafer. Furthermore, it is possible to prevent chipping during dicing due to a decrease in the adhesion of the semiconductor wafer. Here, the glass transition temperature (Tg) means a value measured using a DSC (thermal differential scanning calorimeter) (for example, "Thermo Plus 2" manufactured by Rigaku Co., Ltd.). The Tg of component (B) is the type and content of the structural units that constitute component (B) (if component (B) is an acrylic resin (acrylic rubber), the structural unit derived from (meth)acrylic ester). can be adjusted to a desired range by adjusting .

The weight average molecular weight (Mw) of component (B) may be from 100,000 to 3,000,000 or from 200,000 to 1,000,000. When the Mw of component (B) is within this range, film formability, film strength, flexibility, tackiness, etc. can be appropriately controlled, and reflowability is excellent and embeddability is improved. I can do it. Here, Mw means a value measured by gel permeation chromatography (GPC) and converted using a standard polystyrene calibration curve. In addition, when a plurality of peaks are observed in GPC, the weight average molecular weight resulting from the peak with the highest peak intensity is defined as the weight average molecular weight in this specification.

Commercial products of component (B) include SG-70L, SG-708-6, WS-023 EK30, SG-P3, SG-280 EK23, SG-80H, HTR-860P, HTR-860P-3, HTR- Examples include 860P-3CSP, HTR-860P-3CSP-3DB, and HTR-860P-30B (all manufactured by Nagase ChemteX Corporation).

The content of component (B) may be 15 to 35% by mass based on the total amount of the adhesive film. When the content of component (B) is 15% by mass or more based on the total amount of the adhesive film, the embeddability tends to be further improved, and when it is 40% by mass or less, the adhesive strength of the adhesive film is improved. There is a tendency. The content of component (B) may be 18% by mass or more, 20% by mass or more, or 32% by mass or less, 30% by mass or less, or 28% by mass or less, based on the total amount of the adhesive film. good.

(C1) component: first inorganic filler (C2) component: second inorganic filler The adhesive film contains the (C1) component and the (C2) component. The component (C1) and the component (C2) satisfy all of the following conditions. By containing the components (C1) and (C2), it becomes possible to suppress bleeding when embedding a semiconductor chip or wire, and furthermore, it becomes possible to improve the breaking strength after curing.
- The average particle size of component (C1) is 300 to 1000 nm.
- The average particle size of component (C2) is 0.05 to 0.70 times the average particle size of component (C1).
- The total content of component (C1) and component (C2) is 30 to 60% by mass based on the total amount of the adhesive film.

Component (C1) and component (C2) are, for example, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate. The material may be at least one selected from whiskers, boron nitride, and silica. From the viewpoint of adjusting the melt viscosity, the component (C1) and the component (C2) may contain silica.

The average particle size of the component (C1) is 300 to 1000 nm, and may be 350 nm or more, 400 nm or more, or 450 nm or more, and may be 900 nm or less, 800 nm or less, 700 nm or less, or 600 nm or less.

The average particle size of component (C2) may be less than 300 nm, and may be 250 nm or less, 220 nm or less, or 200 nm or less. The average particle size of the component (C2) may be, for example, 10 nm or more, 50 nm or more, or 100 nm or more.

In this specification, these average particle diameters mean particle diameters with a cumulative frequency of 50% in the particle size distribution determined by laser diffraction/scattering method. Note that the average particle diameter of the (C1) component and the (C2) component can also be determined by using an adhesive film containing the (C1) component and the (C2) component. In this case, the residue obtained by heating the adhesive film to decompose the resin component is dispersed in a solvent to prepare a dispersion liquid, and from the particle size distribution obtained by applying laser diffraction/scattering method to this, it is found that The value of the peak in the range of 1000 nm can be taken as the average particle size of the component (C1), and the value of the peak in the range of less than 300 nm can be taken as the average particle size of the component (C2).

The average particle size of component (C2) is 0.05 to 0.70 times the average particle size of component (C1). The average particle size of the component (C2) may be 0.10 times or more, 0.20 times or more, or 0.30 times or more, and 0.60 times the average particle size of the component (C1). Below, it may be 0.50 times or less, or 0.40 times or less.

The content of the component (C1) may be 5 to 40% by mass, based on the total amount of the adhesive film, and may be 6% by mass or more, 8% by mass or more, or 10% by mass or more, and 35% by mass. Below, it may be 32% by mass or less, or 30% by mass or less.

The content of the component (C2) may be 10 to 50% by mass, and may be 15% by mass or more, 18% by mass or more, or 20% by mass or more, and 45% by mass, based on the total amount of the adhesive film. Below, it may be 42% by mass or less, or 40% by mass or less.

The total content of component (C1) and component (C2) is 30 to 60% by mass, based on the total amount of the adhesive film, and may be 35% by mass or more, 40% by mass or more, or 45% by mass or more. Often, it may be 55% by weight or less, 52% by weight or less, or 50% by weight or less.

The mass ratio of component (C1) to the total of components (C1) and (C2) may be 10 to 70% by mass, and may be 15% by mass or more, 18% by mass or more, or 20% by mass or more. Often, it may be 65% by weight or less, 62% by weight or less, or 60% by weight or less.

The mass ratio of component (C2) to the total of components (C1) and (C2) may be 30 to 90% by mass, and may be 35% by mass or more, 38% by mass or more, or 40% by mass or more. It may be 85% by weight or less, 82% by weight or less, or 80% by weight or less.

Component (D): Curing accelerator Examples of the component (D) include imidazoles and derivatives thereof, organic phosphorus compounds, secondary amines, tertiary amines, and quaternary ammonium salts. These may be used alone or in combination of two or more. Among these, from the viewpoint of reactivity, component (D) may be imidazoles and derivatives thereof.

Examples of imidazoles include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-methylimidazole. These may be used alone or in combination of two or more.

Component (E): Coupling agent Component (E) may be a silane coupling agent. Examples of the silane coupling agent include γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, and 3-(2-aminoethyl)aminopropyltrimethoxysilane. It will be done. These may be used alone or in combination of two or more.

The adhesive film may further contain other components. Examples of other components include pigments, ion scavengers, antioxidants, and the like.

The total content of component (D), component (E), and other components is 0.1% by mass or more, 0.3% by mass or more, or 0.5% by mass or more based on the total amount of the adhesive film. It may be 30% by mass or less, 20% by mass or less, 10% by mass or less, or 5% by mass or less.

The adhesive film 10 can be formed, for example, by applying a thermosetting adhesive to a support film. In forming the adhesive film 10, a thermosetting adhesive varnish (adhesive varnish) may be used. When using an adhesive varnish, the (A) component, (B) component, (C1) component, and (C2) component, and optionally added components are mixed or kneaded in a solvent to create the adhesive varnish. The adhesive film 10 can be obtained by preparing the adhesive varnish, applying the obtained adhesive varnish to a support film, and removing the solvent by heating and drying.

The support film is not particularly limited as long as it can withstand the above heat drying, but examples include polyester film, polypropylene film, polyethylene terephthalate film, polyimide film, polyetherimide film, polyethylene naphthalate film, polymethylpentene film, etc. It's good. The support film may be a multilayer film made of a combination of two or more types, or the surface may be treated with a silicone-based, silica-based, or the like release agent. The thickness of the support film may be, for example, 10-200 μm or 20-170 μm.

Mixing or kneading can be carried out using a dispersing machine such as an ordinary stirrer, a sieve machine, a three-roll mill, a ball mill, etc., or by appropriately combining these dispersing machines.

The solvent used for preparing the adhesive varnish is not limited as long as it can uniformly dissolve, knead, or disperse each component, and conventionally known solvents can be used. Examples of such solvents include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, dimethyl formamide, dimethyl acetamide, N-methyl pyrrolidone, toluene, and xylene. The solvent may be methyl ethyl ketone or cyclohexanone from the viewpoint of drying speed and cost.

As a method for applying the adhesive varnish to the support film, a known method can be used, such as a knife coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, a curtain coating method, etc. be able to. The heating drying conditions are not particularly limited as long as the solvent used is sufficiently volatilized, but may be, for example, 50 to 150° C. for 1 to 30 minutes.

The thickness of the adhesive film 10 may be, for example, 1 μm or more, 3 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, 50 μm or more, 60 μm or more, 70 μm or more, or 80 μm or more, and 200 μm or less. , 150 μm or less, 120 μm or less, 100 μm or less, 80 μm or less, or 60 μm or less. When the adhesive film 10 is an adhesive film for FOD, the thickness of the adhesive film 10 is, for example, 40 to 200 μm, 60 to 150 μm, or 80 to 80 μm, in order to properly embed the entire semiconductor chip (for example, a controller chip). It may be 120 μm. When the adhesive film 10 is an FOW adhesive film, the thickness of the adhesive film 10 is, for example, 20 to 120 μm, 25 to 80 μm, or 30 to 60 μm in order to embed the wire so that the wire does not contact the semiconductor chip. It's good.

According to the findings of the present inventors, the shear viscosity of the adhesive film 10 in the range of 60 to 150° C., particularly at a frequency of 4.4 Hz, is related to the degree of bleeding of the adhesive film 10. FOD or The embeddability in FOW tends to be improved.

At 60 to 150° C., the minimum value of shear viscosity at a frequency of 4.4 Hz exhibited by the adhesive film 10 may be 3200 Pa·s or more or 3500 Pa·s or more from the viewpoint of suppressing bleeding.

At 60 to 150° C., the maximum value of shear viscosity at a frequency of 4.4 Hz exhibited by the adhesive film 10 is 180,000 Pa.s or less, 175,000 Pa.s or less, 170,000 Pa.s or less, or 165,000 Pa. - May be less than s.

The adhesive film 10 produced on the support film may be provided with a cover film on the side of the adhesive film opposite to the support film from the viewpoint of preventing damage or contamination. Examples of the cover film include polyethylene film, polypropylene film, and film treated with a surface release agent. The thickness of the cover film may be, for example, 15-200 μm or 30-170 μm.

The adhesive film 10 is, for example, a protective sheet for protecting the back side of a semiconductor element (semiconductor chip) of a flip-chip type semiconductor device, or a protective sheet for protecting the surface of a semiconductor element (semiconductor chip) of a flip-chip type semiconductor device and an adherend. It can be used as a sealing sheet for sealing between spaces.

[Dicing/die bonding integrated film]
2 and 3 are schematic cross-sectional views showing one embodiment of a laminate including an adhesive film. The adhesive film 10 may be supplied in the form of a laminate shown in FIG. 2 or 3. The laminate 100 shown in FIG. 2 includes a base layer 20 and an adhesive film 10 provided on the base layer 20. The laminate 110 shown in FIG. 3 further includes a protective film 30 provided on the surface of the adhesive film 10 opposite to the base layer 20 with respect to the laminate 100.

The base layer 20 may be a resin film similar to the support film. The thickness of the base material layer 20 may be, for example, 10 to 200 μm or 20 to 170 μm.

The base material layer 20 may be a dicing film. A laminate in which the base material layer 20 is a dicing film can be used as a dicing/die bonding integrated film. The dicing/die bonding integrated film may be in the form of a film, a sheet, or a tape.

Examples of the dicing film include resin films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. The dicing film may be a resin film that has been surface-treated by primer coating, UV treatment, corona discharge treatment, polishing treatment, or etching treatment, as necessary. The dicing film may have adhesive properties. The dicing film having adhesiveness may be, for example, a resin film imparted with adhesiveness, or a laminated film having a resin film and an adhesive layer provided on one side thereof. The adhesive layer can be formed from a pressure-sensitive or ultraviolet curing adhesive. A pressure-sensitive adhesive is an adhesive that exhibits a certain level of tackiness when pressure is applied for a short period of time. An ultraviolet curable adhesive is an adhesive whose adhesive property decreases when irradiated with ultraviolet rays. The thickness of the adhesive layer can be set as appropriate depending on the shape and dimensions of the semiconductor device, and may be, for example, 1 to 100 μm, 5 to 70 μm, or 10 to 40 μm. The thickness of the base material layer 20, which is a dicing film, may be 60 to 150 μm or 70 to 130 μm from the viewpoint of economical efficiency and ease of handling the film.

The protective film 30 may be a resin film similar to the cover film. The thickness of the protective film 30 may be, for example, 15 to 200 μm or 30 to 170 μm.

[Semiconductor device and its manufacturing method]
FIG. 4 is a schematic cross-sectional view showing one embodiment of a semiconductor device, and shows an example of a semiconductor device manufactured using an adhesive film. The semiconductor device 200 shown in FIG. 4 mainly includes a substrate 14, a first semiconductor chip Wa and a second semiconductor chip Waa mounted on the substrate 14, and a sealing layer that seals the second semiconductor chip Waa. 42, and an adhesive film 10 that adheres the second semiconductor chip Waa to the substrate 14. The substrate 14 includes an organic substrate 90 and circuit patterns 84 and 94 provided on the organic substrate 90. The first semiconductor chip Wa is bonded to the substrate 14 with an adhesive 41. A first wire 88 is connected to the first semiconductor chip Wa, and the first semiconductor chip Wa is electrically connected to the circuit pattern 84 via the first wire 88. The entire first semiconductor chip Wa and the entire first wire 88 are embedded in the adhesive film 10. A second wire 98 is connected to the second semiconductor chip Waa, and the second semiconductor chip Waa is electrically connected to the circuit pattern 84 via the second wire 98. The entire second semiconductor chip Waa and the entire second wire 98 are embedded in the sealing layer 42.

5, FIG. 6, FIG. 7, FIG. 8, and FIG. 9 are process diagrams showing one embodiment of a method for manufacturing a semiconductor device, and are process diagrams showing an example of a method for manufacturing the semiconductor device 200 shown in FIG. It is. The method shown in FIGS. 5 to 9 includes bonding the first semiconductor chip Wa to the substrate 14 via the adhesive 41, and connecting the first semiconductor chip Wa and the substrate 14 (circuit pattern 84). Providing the first wire 88; preparing a chip with an adhesive having the second semiconductor chip Wbb and the adhesive film 10 attached thereto; and pressing the chip with the adhesive onto the substrate 14; bonding the second semiconductor chip Waa to the substrate 14 so that the first semiconductor chip Wa and the first wire 88 are embedded in the adhesive film 10; and bonding the second semiconductor chip Waa and the substrate 14 (circuit pattern 84); and providing a second wire 98 connecting the two. Thereafter, by forming the sealing layer 44, the semiconductor device 200 shown in FIG. 4 can be obtained.

The thickness of the first semiconductor chip Wa may be 10 to 170 μm. The first semiconductor chip Wa may be a controller chip for driving the semiconductor device 200. The first semiconductor chip Wa may be a flip chip type chip. The size of the first semiconductor chip Wa is usually smaller than the size of the second semiconductor chip Waa. The adhesive 41 interposed between the first semiconductor chip Wa and the substrate 14 may be a known semiconductor adhesive used in the field.

As shown in FIG. 5, the substrate 14 (circuit pattern 84) and the first semiconductor chip Wa are electrically connected via the first wire 88. The first wire 88 connecting the first semiconductor chip Wa and the substrate 14 (circuit pattern 84) may be, for example, a gold wire, an aluminum wire, or a copper wire. The heating temperature for the connection of the first wire 88 may be in the range of 80-250°C or 80-220°C. The heating time for connecting the first wire 88 may be from several seconds to several minutes. For connection of the first wire 88, vibration energy by ultrasonic waves and compression energy by applied pressure may be applied.

The adhesive-attached chip consisting of the second semiconductor chip Waa and the adhesive film 10 can be prepared using, for example, a dicing/die bonding integrated film having the same configuration as the laminate 100 shown in FIG. 2. In this case, for example, the laminate 100 (dicing/die bonding integrated film) is attached to one side of the semiconductor wafer with the adhesive film 10 in contact with the semiconductor wafer. The surface to which the adhesive film 10 is attached may be the circuit surface of the semiconductor wafer, or may be the opposite back surface. By dividing the semiconductor wafer to which the laminate 100 (integrated dicing/die bonding film) is attached by dicing, second semiconductor chips Waa are formed into individual pieces. Examples of dicing include blade dicing using a rotary blade, stealth dicing in which a modified region is created in a semiconductor wafer using a laser, and a base material layer is expanded. The second semiconductor chip Waa is picked up together with the divided adhesive film 10. If the adhesive layer of the dicing film is made of an ultraviolet curable adhesive, the adhesive layer may be irradiated with ultraviolet rays to remove the adhesive before picking up the second semiconductor chip Waa. The adhesion of the layer may also be reduced.

The second semiconductor chip Waa may have a width of 20 mm or less. The width (or length of one side) of the second semiconductor chip Waa may be 3 to 15 mm or 5 to 10 mm.

The semiconductor wafer used to form the second semiconductor chip Waa may be a thin semiconductor wafer having a thickness of 10 to 100 μm, for example. In addition to single crystal silicon, the semiconductor wafer may be a wafer of polycrystalline silicon, various ceramics, or compound semiconductors such as gallium arsenide. The second semiconductor chip Waa may also be formed from a similar semiconductor wafer.

As shown in FIG. 7, an adhesive-attached chip consisting of an adhesive film 10 and a second semiconductor chip Waa is placed so that the adhesive film 10 covers the first wire 88 and the first semiconductor chip Wa. . Next, as shown in FIG. 8, the second semiconductor chip Waa is fixed to the substrate 14 by pressing the second semiconductor chip Waa onto the substrate 14. The heating temperature for compression bonding may be 50 to 200°C or 100 to 150°C. If the heating temperature for pressure bonding is high, the adhesive film 10 becomes soft and embeddability tends to improve. The crimping time may be 0.5 to 20 seconds or 1 to 5 seconds. The pressure for crimping may be 0.01-5 MPa or 0.02-2 MPa.

After crimping, the structure including the adhesive film 10 may be further heated, thereby curing the adhesive film 10. The temperature and time for curing can be appropriately set depending on the curing temperature of the adhesive film 10 and the like. The temperature may be changed stepwise. The heating temperature may be, for example, 40-300°C or 60-200°C. The heating time may be, for example, 30 to 300 minutes.

As shown in FIG. 9, the substrate 14 and the second semiconductor chip Waa are electrically connected via the second wire 98. The type and connection method of the second wire 98 may be the same as that of the first wire 88.

Thereafter, the sealing layer 42 that seals the circuit pattern 84, the second wire 98, and the second semiconductor chip Waa is formed using a sealing material. The sealing layer 42 can be formed, for example, by a conventional method using a mold. After the sealing layer 42 is formed, the adhesive film 10 and the sealing layer 42 may be further thermally cured by heating. The heating temperature for this may be, for example, 165 to 185° C., and the heating time may be about 0.5 to 8 hours.

FIG. 10 is a schematic cross-sectional view showing another embodiment of the semiconductor device. The semiconductor device 201 mainly includes a substrate 14, a first semiconductor chip Wa and a second semiconductor chip Waa mounted on the substrate 14, and a seal that seals the first semiconductor chip Wa and the second semiconductor chip Waa. It is composed of a stop layer 42 and an adhesive film 10 that adheres the second semiconductor chip Waa to the first semiconductor chip Wa. The substrate 14 includes an organic substrate 90, circuit patterns 84, 94 provided on the organic substrate 90, and connection terminals 95 provided on the surface of the organic substrate 90 opposite to the circuit patterns 84, 94. . The first semiconductor chip Wa is bonded to the substrate 14 with an adhesive 41. A first wire 88 is connected to the first semiconductor chip Wa, and the first semiconductor chip Wa is electrically connected to the circuit pattern 84 via the first wire 88. A portion of the first wire 88 is embedded in the adhesive film 10. A second wire 98 is connected to the second semiconductor chip Waa, and the second semiconductor chip Waa is electrically connected to the circuit pattern 84 via the second wire 98.

The semiconductor device 201 shown in FIG. 10 can be manufactured by the same method as the manufacturing method of the semiconductor device 200, which includes bonding the second semiconductor chip Waa to the first semiconductor chip Wa using the adhesive film 10. .

FIG. 11 is a schematic cross-sectional view showing another embodiment of the semiconductor device. The semiconductor device 202 mainly includes a substrate 14 (organic substrate 90), a first semiconductor chip Wa and a second semiconductor chip Waa mounted on the substrate 14, and a first semiconductor chip Wa and a second semiconductor chip Waa. and an adhesive film 10 that adheres the second semiconductor chip Waa to the substrate 14 while embedding the entire first semiconductor chip Wa. The first semiconductor chip Wa is a flip-chip type chip, and is electrically connected to the substrate 14 via a plurality of electrodes 96. An underfill 50 is filled between the first semiconductor chip Wa and the substrate 14.

The present disclosure will be specifically described below based on Examples, but the present disclosure is not limited thereto.

[Preparation of adhesive film]
(Examples 1 to 3 and Comparative Examples 1 to 5)
<Preparation of adhesive varnish>
Cyclohexanone was added to a composition consisting of component (A), component (C1), and component (C2) with the product name and composition ratio (unit: parts by mass) shown in Table 1, and the mixture was stirred. To this, the (B) component shown in Table 1 was added and stirred, and the (D) component and (E) component shown in Table 1 were further added and stirred until each component became uniform. Adhesive varnishes of No. 3 and Comparative Examples 1 to 5 were prepared. Note that the numerical values of component (B), component (C1), and component (C2) shown in Table 1 mean parts by mass of solid content.

(A) Component: Thermosetting resin component (A1) Component: Thermosetting resin (A1-1) N-500P-10 (trade name, manufactured by DIC Corporation, o-cresol novolac type epoxy resin, epoxy equivalent: 204 g /eq, softening point: 75-85℃)
(A1-2) EXA-830CRP (product name, manufactured by DIC Corporation, liquid bisphenol F type epoxy resin, epoxy equivalent: 159 g/eq)

(A2) Component: Curing agent (A2-1) MEH-7800M (trade name, manufactured by Meiwa Chemical Co., Ltd., phenylaralkyl type phenol resin, hydroxyl equivalent: 174 g/eq, softening point: 80°C)
(A2-2) PSM-4326 (trade name, manufactured by Gunei Chemical Co., Ltd., phenol novolac resin, hydroxyl equivalent: 105 g/eq, softening point: 120°C)

(B) Component: Elastomer (B-1) Acrylic resin A (HTR-860P-3CSP (trade name), Nagase ChemteX Co., Ltd., acrylic resin, weight average molecular weight: 800,000, Tg: 12°C)
(B-2) Acrylic resin B (acrylic resin which is a copolymer of butyl acrylate/ethyl acrylate/ethyl methacrylate/glycidyl methacrylate/styrene, weight average molecular weight: 400,000, Tg: 5°C)

(C1) Component: First inorganic filler (C1-1) Silica filler A (SC2050-HLG (trade name), manufactured by Admatex Co., Ltd., silica filler dispersion, average particle size: 500 nm)
(C2) Component: Second inorganic filler (C2-1) Silica filler B (silica filler dispersion, average particle size: 180 nm)

(D) Curing accelerator (D-1) 2PZ-CN (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd., 1-cyanoethyl-2-phenylimidazole)

(E) Component: Coupling agent (E-1) A-189 (trade name, manufactured by Nippon Unicar Co., Ltd., γ-mercaptopropyltrimethoxysilane)
(E-2) A-1160 (trade name, manufactured by Nippon Unicar Co., Ltd., γ-ureidopropyltriethoxysilane)

<Preparation of adhesive film>
The produced adhesive varnish was filtered through a 100 mesh filter and degassed under vacuum. As a base material layer, a polyethylene terephthalate (PET) film having a thickness of 38 μm and subjected to a mold release treatment was prepared, and an adhesive varnish after vacuum defoaming was applied onto the PET film. The applied adhesive varnish was heated and dried in two steps: at 90°C for 5 minutes and then at 140°C for 5 minutes, and the adhesive films of Examples 1 to 3 and Comparative Examples 1, 2, and 5 in the B-stage state were dried. Obtained. In addition, when the adhesive varnishes of Comparative Examples 3 and 4 were used, the film forming properties were not sufficient and an adhesive film could not be obtained. In the adhesive films of Examples 1 to 3 and Comparative Examples 1, 2, and 5, the thickness was adjusted to 60 μm depending on the amount of adhesive varnish applied. Two sheets of the obtained adhesive film with a thickness of 60 μm were prepared and bonded together at 70° C. to produce an adhesive film with a thickness of 120 μm.

[Evaluation of adhesive film]
<Measurement of shear viscosity>
The shear viscosity was measured by the following method. That is, a plurality of adhesive films of Examples 1 to 3 and Comparative Examples 1, 2, and 5 were each laminated to a thickness of about 1000 μm, and a sample for measurement was obtained by punching out a circle with a diameter of 9 mm. A circular aluminum plate jig with a diameter of 8 mm was set in a dynamic viscoelasticity device ARES (trade name, manufactured by TA Instruments), and a sample was further set on the jig. Thereafter, the shear viscosity was measured under the following measurement conditions, and the minimum value of the shear viscosity within the range of 60 to 150° C. was read from the measurement results. The results are shown in Table 1. The larger the minimum value of the shear viscosity (for example, 3000 Pa·s or more) tends to suppress bleeding when embedding a semiconductor chip or wire.
(Measurement condition)
・Measurement temperature: 35-160℃
・Heating rate: 5℃/min ・Strain: 5%
・Frequency: 4.4Hz
・Initial load: 10g

<Evaluation of embeddability>
(Production of semiconductor chip with adhesive film)
A semiconductor wafer (thickness 40 μm) was pasted. It was cut by dicing using a fully automatic dicer DFD-6361 (manufactured by DISCO Co., Ltd.) to form a semiconductor chip (controller chip) having a size of 1.6 mm x 4 mm. A semiconductor chip with an adhesive film consisting of a controller chip and an adhesive film attached thereto was picked up to obtain a first semiconductor chip. Next, a dicing film (manufactured by Showa Denko Materials Co., Ltd., thickness 100 μm) having a resin film and an adhesive layer was prepared, and the adhesive films of Examples 1 to 3 and Comparative Examples 1, 2, and 5 (thickness 120 μm) to produce a dicing/die bonding integrated film including a dicing film and an adhesive film provided on one surface of the dicing film. Next, a semiconductor wafer (thickness: 90 μm) was attached to the adhesive film side of the dicing/die bonding integrated film at a stage temperature of 70° C. It was cut by dicing using a fully automatic dicer DFD-6361 (manufactured by DISCO Co., Ltd.) to form a semiconductor chip having a size of 6 mm x 12 mm. A semiconductor chip with an adhesive film made of a semiconductor chip and an adhesive film attached thereto was picked up to obtain a second semiconductor chip.

(Preparation of laminate for evaluation)
An organic substrate for pressure-bonding the first semiconductor chip and the second semiconductor chip was prepared. A first semiconductor chip was crimped onto this substrate via an adhesive film using a crimping machine (die bonder manufactured by Besi, trade name: Esec 2100sD PPPplus) under conditions of 120° C., 20 N, and 1.5 seconds. Next, a second semiconductor chip was pressure-bonded via the adhesive film to be evaluated under conditions of 120° C., 20 N, and 1.5 seconds so as to cover the first semiconductor chip. At this time, the positions of the first semiconductor chip and the second semiconductor chip, which were press-bonded earlier, were aligned so that their center positions coincided in a plan view. Thereafter, the adhesive film was cured by heating at 130° C. for 1 hour at a temperature increase rate of 15° C./min to obtain a laminate for evaluation.

(Observation of voids)
The obtained evaluation laminate was analyzed using an ultrasonic imaging device (SAT) (trade name: IS-350, manufactured by Insight Co., Ltd.) to evaluate the presence or absence of voids. The case where the generation of voids was not confirmed was evaluated as "A" as being excellent in terms of embeddability, and the case where the generation of voids was confirmed at least partially was evaluated as "B". The results are shown in Table 1.

<Evaluation of bleeding amount>
Regarding the above evaluation laminate, the top surface of the second semiconductor chip was observed using a microscope (trade name: VHX-5000, manufactured by Keyence Corporation). Starting from the end of the second semiconductor chip, the protruding width of the adhesive film from the end was measured. The measurement was performed multiple times, and the maximum value of the protrusion width was taken as the amount of bleed (μm). When the amount of bleeding was less than 100 μm, it was evaluated as “A” as being excellent in suppressing the amount of bleeding, and when the amount of bleeding was 100 μm or more, it was evaluated as “B”. The results are shown in Table 1.

<Measurement of breaking strength>
(Preparation of cured product)
Samples for measurement of breaking strength were obtained by cutting the adhesive films (120 μm thick) of Examples 1 to 3 and Comparative Examples 1, 2, and 5 into strips with a width of 10 mm and a length of 60 mm, and heating and curing them at 175° C. for 5 hours. As a result, a cured adhesive film (thickness: 120 μm) was obtained.

(Measurement of breaking strength)
The breaking strength of the produced cured adhesive film at 125° C. was measured using a tensile tester (UTM-III-500, manufactured by TOYO BALDWIN). The breaking strength of the above cured adhesive film was measured based on JIS K7161 under conditions of a distance between chucks of 40 mm and a tensile speed of 300 mm/min. The results are shown in Table 1. The larger the value of the breaking strength (for example, 12 MPa or more), the more likely it is that defects such as cracking can be suppressed.

As shown in Table 1, the adhesive films of Examples 1 to 3 in which a predetermined inorganic filler was combined were superior to the adhesive films of Comparative Examples 1 to 5 in which a predetermined inorganic filler was not combined. It was also excellent in terms of breaking strength after curing. From these results, it was confirmed that the adhesive film for semiconductors of the present disclosure can suppress bleeding when embedding a semiconductor chip or wire, and has sufficient breaking strength after curing.

DESCRIPTION OF SYMBOLS 10... Adhesive film, 14... Substrate, 20... Base material layer (dicing film), 30... Protective film, 41... Adhesive, 42... Sealing layer, 84, 94... Circuit pattern, 88... First wire, 90 ...Organic substrate, 98...Second wire, 100, 110...Laminated body, 200...Semiconductor device, Wa...First semiconductor chip, Waa...Second semiconductor chip.

Claims (12)

An adhesive film for semiconductors containing a thermosetting component, an elastomer, a first inorganic filler, and a second inorganic filler,
The average particle size of the first inorganic filler is 300 to 1000 nm,
The average particle size of the second inorganic filler is 0.05 to 0.70 times the average particle size of the first inorganic filler,
The total content of the first inorganic filler and the second inorganic filler is 30 to 60% by mass based on the total amount of the semiconductor adhesive film.
Adhesive film for semiconductors. having a thickness of 60 to 150 μm,
The adhesive film for semiconductors according to claim 1. The adhesive film for semiconductors according to claim 1 or 2, which is used for adhering a semiconductor chip to a substrate while embedding another semiconductor chip. having a thickness of 25 to 80 μm,
The adhesive film for semiconductors according to claim 1. Used for bonding a semiconductor chip to another semiconductor chip while embedding part or all of the wires connected to the other semiconductor chip.
The adhesive film for semiconductors according to claim 1 or 4. The content of the elastomer is 15 to 35% by mass based on the total amount of the semiconductor adhesive film,
The adhesive film for semiconductors according to any one of claims 1 to 5. The content of the thermosetting component is 10 to 40% by mass based on the total amount of the semiconductor adhesive film.
The adhesive film for semiconductors according to any one of claims 1 to 6. The thermosetting component includes a liquid epoxy resin that is liquid at 30°C,
The content of the liquid epoxy resin is 5 to 20% by mass based on the total amount of the semiconductor adhesive film.
The adhesive film for semiconductors according to any one of claims 1 to 7. dicing film and
The adhesive film for semiconductor according to any one of claims 1 to 8 provided on the dicing film,
Equipped with
Integrated dicing and die bonding film. Adhering a second semiconductor chip to the substrate on which the first semiconductor chip is mounted, using the semiconductor adhesive film according to claim 1 or 2,
the first semiconductor chip is embedded by the adhesive film;
A method for manufacturing a semiconductor device. bonding a second semiconductor chip to the first semiconductor chip using the semiconductor adhesive film according to claim 1 or 4;
A wire is connected to the first semiconductor chip,
Part or all of the wire is embedded by the adhesive film.
A method for manufacturing a semiconductor device. the first semiconductor chip is a controller chip;
The method for manufacturing a semiconductor device according to claim 10 or 11.

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