Dicing and die bonding integrated film, die bonding film, and method for manufacturing semiconductor device

Abstract

To provide a dicing / die bonding integrated film with excellent heat dissipation.SOLUTION: An dicing / die bonding integrated film 100 has base material 40, a dicing tape 50 having a clinging layer 30 provided on the base material 40, and a die bonding film 10 disposed on the clinging layer 30 of the dicing tape 50. The die bonding film 10 contains silver-containing particles having an oxide layer on the surface and a fluxing agent. The content of the silver-containing particles is 75 mass% or more, based on the total amount of the die bonding film 10.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a dicing / die bonding integrated film, a die bonding film, and a method for manufacturing a semiconductor device. [Background technology]

[0002] Conventionally, semiconductor devices are manufactured through the following steps. First, a semiconductor wafer is attached to a dicing adhesive sheet, and in this state, the semiconductor wafer is diced into semiconductor chips (dicing step). Then, a pick-up step, a pressure bonding step, a die bonding step, etc. are performed. Patent Document 1 discloses an adhesive sheet (dicing die bonding sheet) that has both the function of fixing the semiconductor wafer in the dicing step and the function of adhering the semiconductor chip to a substrate in the die bonding step. In the dicing step, the semiconductor wafer and the adhesive layer are diced into individual chips with adhesive pieces attached.

[0003] In recent years, devices called power semiconductor devices that control electric power and the like have become widespread. Power semiconductor devices tend to generate heat due to the current supplied to them, and therefore require excellent heat dissipation. Patent Document 2 discloses a conductive film-like adhesive and a dicing tape with a film-like adhesive that have higher heat dissipation properties after curing than before curing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-218571 A [Patent Document 2] Patent No. 6396189 Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional dicing and die bonding integrated films do not have sufficient heat dissipation properties and there is still room for improvement.

[0006] Therefore, one aspect of the present disclosure aims to provide a dicing / die bonding integrated film having excellent heat dissipation properties. [Means for solving the problem]

[0007] The present inventors conducted intensive research to solve the above problems and found that when silver-containing particles have an oxide layer (oxide film) on the surface, the heat dissipation tends to be insufficient compared to particles that do not have an oxide layer (oxide film). After further research, the present inventors found that excellent heat dissipation can be achieved by adding a flux agent to the die bonding film, and thus completed the present invention.

[0008] One aspect of the present disclosure relates to a dicing-die bonding integrated film. The dicing-die bonding integrated film contains silver-containing particles having an oxide layer (oxide film) on the surface and a fluxing agent. The content of the silver-containing particles is 75 mass% or more based on the total amount of the die bonding film. Such a dicing-die bonding integrated film can have excellent heat dissipation properties. The reason why such an effect is exhibited is not necessarily clear, but it is thought that, for example, the fluxing agent sufficiently reduces and removes the oxide layer (oxide film) on the metal surface, and the state is further maintained.

[0009] The fluxing agent may be an aromatic carboxylic acid. In a dicing-die bonding integrated film having an adhesive layer and an adhesive layer, if the adhesive strength between the adhesive layer and the adhesive layer is not sufficiently reduced, a problem may occur in that the chip with the adhesive piece cannot be picked up from the adhesive layer in the subsequent pick-up process. By using an aromatic carboxylic acid as the fluxing agent, it is possible to sufficiently reduce the adhesive strength between the adhesive layer and the adhesive layer after ultraviolet irradiation.

[0010] The die bonding film may further contain a thermosetting resin, a curing agent, and an elastomer. The die bonding film containing these tends to have an easier adjustment of the surface roughness (Ra).

[0011] The thermosetting resin may contain an epoxy resin that is liquid at 25° C. When the thermosetting resin contains such an epoxy resin, a die bonding film with improved surface roughness (Ra) tends to be obtained.

[0012] Another aspect of the present disclosure relates to a method for manufacturing a semiconductor device. The method for manufacturing a semiconductor device includes a step of attaching the die bonding film of the dicing-die bonding integrated film described above to a semiconductor wafer, a step of singulating the semiconductor wafer and the die bonding film, a step of picking up the semiconductor chip to which the die bonding film piece is attached from the dicing tape, and a step of adhering the semiconductor chip to a support substrate via the die bonding film piece. The method for manufacturing a semiconductor device may further include a step of irradiating the adhesive layer with ultraviolet light after the step of singulating the semiconductor wafer and the die bonding film. According to such a method for manufacturing a semiconductor device, since the dicing-die bonding integrated film described above is used, it is possible to manufacture a semiconductor device having excellent heat dissipation properties.

[0013] Another aspect of the present disclosure relates to a die bonding film. The die bonding film contains silver-containing particles having an oxide layer on the surface and a fluxing agent. The content of the silver-containing particles is 75 mass% or more based on the total amount of the die bonding film. Effect of the Invention

[0014] According to the present disclosure, a dicing-die bonding integrated film having excellent heat dissipation properties is disclosed. The dicing-die bonding integrated film according to some embodiments can sufficiently reduce the adhesive strength between the adhesive layer and the adhesive layer after ultraviolet irradiation. In addition, according to the present disclosure, a method for manufacturing a semiconductor device using such a dicing-die bonding integrated film is provided. Furthermore, according to the present disclosure, a die bonding film suitable for use in such a dicing-die bonding integrated film is provided. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of a die bonding film. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing one embodiment of a dicing / die bonding integrated film. [Diagram 3] 3A, 3B, 3C, 3D, 3E, and 3F are schematic cross-sectional views showing one embodiment of a method for manufacturing a semiconductor device, in which (a), (b), (c), (d), (e), and (f) are schematic cross-sectional views showing each step. [Figure 4] FIG. 4 is a schematic cross-sectional view showing one embodiment of a semiconductor device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the embodiments of the present disclosure will be described with reference to the drawings as appropriate. However, the present disclosure is not limited to the following embodiments. In the following embodiments, the components (including steps, etc.) are not essential unless specifically stated. The size of the components in each figure is conceptual, and the relative relationship of the size between the components is not limited to that shown in each figure.

[0017] The same applies to the numerical values ​​and their ranges in this specification, and they do not limit the present disclosure. In this specification, a numerical range indicated using "~" indicates a range including the numerical values ​​before and after "~" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this specification, the upper limit or lower limit value described in one numerical range may be replaced with the upper limit or lower limit value of another numerical range described in stages. In addition, in the numerical ranges described in this specification, the upper limit or lower limit value of the numerical range may be replaced with a value shown in the examples.

[0018] In this specification, (meth)acrylate means acrylate or the corresponding methacrylate, and the same applies to other similar expressions such as (meth)acryloyl group, (meth)acrylic copolymer, etc.

[0019] [Die bonding film] Fig. 1 is a schematic cross-sectional view showing one embodiment of a die bonding film. The die bonding film 10 shown in Fig. 1 has a first surface 10A and a second surface 10B opposite to the first surface 10A. The first surface 10A can be a surface to be placed on an adhesive layer of a dicing tape, as described below. The die bonding film 10 can be provided on a support film 20, as shown in Fig. 1. The die bonding film 10 is thermosetting, and can be in a semi-cured (B stage) state and then in a completely cured (C stage) state after a curing process.

[0020] The die bonding film 10 contains (a) silver-containing particles having an oxide layer on the surface and (b) a fluxing agent, and may optionally further contain (c) a thermosetting resin, (d) a curing agent, and (f) an elastomer.

[0021] (a) Component: Silver-containing particles having an oxide layer on the surface The component (a) is a component used to enhance the heat dissipation in the die bonding film. The silver-containing particles may be, for example, silver particles made of silver or silver-coated metal particles (such as silver-coated copper particles) in which the surface of metal particles (such as copper particles) is coated with silver. The silver-containing particles may be silver particles made of silver.

[0022] Since silver in the silver-containing particles has a property of being easily oxidized, silver-containing particles that are not surface-treated with a protective material or the like usually tend to have an oxide layer (oxide film) on the surface. The component (a) is not particularly limited as long as it is a silver-containing particle having an oxide layer (oxide film) on the surface, but from the viewpoint of ease of availability, for example, it may be a silver-containing particle manufactured by an atomization method. Here, the atomization method is a method in which a molten metal or alloy is made to flow out from a small hole at the bottom of a crucible to form a thin stream, and high-speed air, nitrogen, argon, water, etc. are sprayed onto it to scatter the molten metal and rapidly cool and solidify it to obtain a powder (particles). The obtained powder is sintered to prevent agglomeration, so that an oxide layer (oxide film) tends to be formed on the surface by oxygen in the air. Examples of such silver-containing particles include Ag-HWQ series (trade name, manufactured by Fukuda Metal Foil and Powder Co., Ltd.), conductive atomized powder (trade name, manufactured by DOWA Electronics Co., Ltd.), etc.

[0023] The average particle size of the (a) component may be 0.01 to 10 μm. When the average particle size of the (a) component is 0.01 μm or more, the viscosity increase when the adhesive varnish is prepared can be prevented, a desired amount of the (a) component can be contained in the die bonding film, and the wettability of the die bonding film to the adherend can be ensured, tending to exhibit better adhesion. When the average particle size of the (a) component is 10 μm or less, the film formability is excellent, and the heat dissipation due to the addition of the (a) component tends to be improved. In addition, by setting the average particle size in this range, the thickness of the die bonding film can be made thinner, and the semiconductor chips can be highly laminated, and the occurrence of chip cracks due to the protrusion of conductive particles from the die bonding film tends to be prevented. The average particle size of the (a) component may be 0.1 μm or more, 0.5 μm or more, 1.0 μm or more, or 1.5 μm or more, and may be 8.0 μm or less, 7.0 μm or less, 6.0 μm or less, 5.0 μm or less, 4.0 μm or less, or 3.0 μm or less. When the average particle size of the (a) component is 5.0 μm or less, a die bonding film with improved surface roughness (Ra) tends to be obtained. The average particle size of the (a) component is the particle size (D) when the ratio (volume fraction) of the volume of the (a) component to the total volume is 50%. 50 (a) Average particle size of the component (D 50 ) can be determined by measuring a suspension of component (a) in water by a laser scattering method using a laser scattering type particle size measuring device (e.g., Microtrac).

[0024] It is preferable that component (a) be in the form of spherical particles with an average particle size of 5.0 μm or less.

[0025] The content of the (a) component is 75% by mass or more based on the total amount of the die bonding film. When the content of the (a) component is 75% by mass or more based on the total amount of the die bonding film, the thermal conductivity of the die bonding film can be improved, and as a result, the heat dissipation property can be improved. The content of the (a) component may be 77% by mass or more, 80% by mass or more, 83% by mass or more, or 85% by mass or more based on the total amount of the die bonding film. The upper limit of the content of the (a) component is not particularly limited, but may be 98% by mass or less, 96% by mass or less, or 95% by mass or less based on the total amount of the die bonding film.

[0026] (b) Fluxing agent The component (b) is a component for reducing and removing the oxide layer (oxide film) in the component (a). The component (b) may be, for example, a compound having a carboxy group (carboxylic acid). Examples of such a component (b) include aliphatic carboxylic acids and aromatic carboxylic acids. These may be used alone or in combination of two or more. The component (b) may be solid at 25°C.

[0027] Examples of the aliphatic carboxylic acid include succinic acid (melting point: 184°C), glutaric acid (melting point: 95 to 98°C), adipic acid (melting point: 152°C), pimelic acid (melting point: 103 to 105°C), suberic acid (melting point: 141 to 144°C), azelaic acid (melting point: 109°C), sebacic acid (melting point: 133 to 137°C), undecanedioic acid (melting point: 28 to 31°C), dodecanedioic acid (melting point: 127 to 129°C), etc. The aliphatic carboxylic acid may be, for example, glutaric acid.

[0028] Examples of aromatic carboxylic acids include diphenylacetic acid (melting point: 147 to 149°C), benzilic acid (melting point: 150 to 152°C), 4,4-bis(4-hydroxyphenyl)valeric acid (melting point: 147 to 177°C), 2,5-dihydroxybenzoic acid (melting point: 200 to 205°C), 3,4,5-trihydroxybenzoic acid (melting point: 250°C), 1,2,4-benzenetricarboxylic acid (melting point: 231°C), 1,3,5-benzenetricarboxylic acid (melting point: >300°C), and 2-[bis(4-hydroxyphenyl)methyl]benzoic acid (melting point: 126°C). The aromatic carboxylic acid may be, for example, benzilic acid.

[0029] From the viewpoint of sufficiently reducing the adhesive strength between the pressure-sensitive adhesive layer and the adhesive layer after ultraviolet irradiation, the component (b) may be a compound having a carboxy group (carboxylic acid) that satisfies one or more of the following conditions: Component (b) is an aromatic carboxylic acid. The melting point of component (b) is 100°C or higher, preferably 120°C or higher, and more preferably 140°C or higher, and is 200°C or lower, preferably 180°C or lower, and more preferably 160°C or lower. Component (b) is a carboxylic acid having a hydroxyl group.

[0030] Component (b) may be, for example, glutaric acid or benzilic acid, or may be benzilic acid.

[0031] The content of the (b) component may be 0.1 to 15% by mass based on the total amount of the die bonding film. When the content of the (b) component is 0.1% by mass or more based on the total amount of the die bonding film, the oxide layer in the (a) component can be sufficiently reduced and removed, and the heat dissipation property tends to be improved. When the content of the (b) component is 15% by mass or less based on the total amount of the die bonding film, the amount of other components (particularly, the (c), (d), and (e) components) can be sufficiently secured, the adherend of the die bonding film can be secured, and the film formability tends to be excellent. The content of the (b) component may be 0.2% by mass or more, 0.5% by mass or more, 0.8% by mass or more, 1% by mass or more, 1.2% by mass or more, or 1.5% by mass or more based on the total amount of the die bonding film, and may be 12% by mass or less, 10% by mass or less, 8% by mass or less, or 6% by mass or less.

[0032] (c) Component: Thermosetting resin Component (c) is a component that has the property of forming three-dimensional bonds between molecules and curing by heating or the like, and is a component that exhibits adhesive properties after curing. Component (c) may be an epoxy resin. Component (c) may contain an epoxy resin that is liquid at 25°C. The epoxy resin may be any epoxy resin that has an epoxy group in the molecule. The epoxy resin may have two or more epoxy groups in the molecule.

[0033] Examples of epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A novolac type epoxy resins, bisphenol F novolac type epoxy resins, stilbene type epoxy resins, triazine skeleton-containing epoxy resins, fluorene skeleton-containing epoxy resins, triphenol methane type epoxy resins, biphenyl type epoxy resins, xylylene type epoxy resins, biphenyl aralkyl type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene type epoxy resins, polyfunctional phenols, and diglycidyl ether compounds of polycyclic aromatics such as anthracene. These may be used alone or in combination of two or more. Among these, the epoxy resin may be a bisphenol type epoxy resin or a cresol novolac type epoxy resin from the viewpoint of heat resistance of the cured product.

[0034] The epoxy resin may contain an epoxy resin that is liquid at 25° C. By containing such an epoxy resin, a die bonding film with improved surface roughness (Ra) tends to be obtained. Examples of commercially available epoxy resins that are liquid at 25° C. include EXA-830CRP (trade name, manufactured by DIC Corporation) and YDF-8170C (trade name, manufactured by Nippon Steel Chemical & Material Co., Ltd.).

[0035] The epoxy equivalent of the epoxy resin is not particularly limited, but may be 90 to 300 g / eq, 110 to 290 g / eq, or 110 to 290 g / eq. When the epoxy equivalent of the (A) component is within such a range, the bulk strength of the die bonding film is maintained, and the flowability of the adhesive composition when forming the die bonding film tends to be easily ensured.

[0036] The content of the (c) component may be 0.1 mass% or more, 0.5 mass% or more, 1 mass% or more, or 1.5 mass% or more, based on the total amount of the die bonding film, and may be 15 mass% or less, 12 mass% or less, 10 mass% or less, 8 mass% or less, or 6 mass% or less.

[0037] When the (c) component contains an epoxy resin that is liquid at 25° C., the mass ratio of the epoxy resin to the (c) component (mass of the epoxy resin / total mass of the (c) component) may be, in percentage, 10 to 100%, 40 to 100%, 60% to 100%, or 80% to 100%. When the (c) component contains an epoxy resin that is liquid at 25° C., the content of the epoxy resin may be 0.1 mass% or more, 0.5 mass% or more, 1 mass% or more, or 1.5 mass% or more, and may be 15 mass% or less, 12 mass% or less, 10 mass% or less, 8 mass% or less, or 6 mass% or less, based on the total amount of the die bonding film.

[0038] (d) Component: Hardener The component (d) may be a phenolic resin that can be a curing agent for epoxy resins. Any phenolic resin can be used without particular limitation as long as it has a phenolic hydroxyl group in the molecule. Examples of phenolic resins include novolac-type phenolic resins obtained by condensing or co-condensing phenols such as phenol, cresol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol and / or naphthols such as α-naphthol, β-naphthol, and dihydroxynaphthalene with a compound having an aldehyde group such as formaldehyde under an acidic catalyst, allylated bisphenol A, allylated bisphenol F, allylated naphthalenediol, phenol novolac, and phenol aralkyl resins, naphthol aralkyl resins, biphenyl aralkyl-type phenolic resins, and phenyl aralkyl-type phenolic resins synthesized from phenols such as phenol and / or naphthols with dimethoxy-paraxylene or bis(methoxymethyl)biphenyl, and the like. These may be used alone or in combination of two or more.

[0039] The hydroxyl equivalent of the phenol resin may be 40 to 300 g / eq, 70 to 290 g / eq, or 100 to 280 g / eq. When the hydroxyl equivalent of the phenol resin is 40 g / eq or more, the storage modulus of the film tends to be improved, and when it is 300 g / eq or less, defects due to the generation of foaming, outgassing, etc. can be prevented.

[0040] The ratio of the epoxy equivalent of the epoxy resin (c) to the hydroxyl equivalent of the phenol resin (d) (epoxy equivalent of the epoxy resin (c) / hydroxyl equivalent of the phenol resin (d)) may be 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 from the viewpoint of curability. When the equivalent ratio is 0.30 / 0.70 or more, more sufficient curability tends to be obtained. When the equivalent ratio is 0.70 / 0.30 or less, it is possible to prevent the viscosity from becoming too high, and more sufficient fluidity can be obtained.

[0041] The content of the (d) component may be 0.1 mass% or more, 0.3 mass% or more, 0.5 mass% or more, or 1 mass% or more, based on the total amount of the die bonding film, and may be 12 mass% or less, 10 mass% or less, 8 mass% or less, 6 mass% or less, or 4 mass% or less.

[0042] (e) Component: Elastomer Examples of the (e) component include polyimide resin, acrylic resin, urethane resin, polyphenylene ether resin, polyetherimide resin, phenoxy resin, modified polyphenylene ether resin, etc. The (e) component may be any of these resins having a crosslinkable functional group, or may be an acrylic resin having a crosslinkable functional group. Here, the acrylic resin means a polymer containing a structural unit derived from a (meth)acrylic acid ester. The acrylic resin may be a polymer containing 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 carboxy group as a structural unit. The acrylic resin may also be an acrylic rubber such as a copolymer of a (meth)acrylic acid ester and an acrylonitrile. These may be used alone or in combination of two or more.

[0043] Commercially available acrylic resins include, for example, SG-70L, SG-708-6, WS-023 EK30, SG-280 EK23, HTR-860P-3, HTR-860P-3CSP, and HTR-860P-3CSP-3DB (all manufactured by Nagase ChemteX Corporation).

[0044] The glass transition temperature (Tg) of the (e) component may be -50 to 50°C or -30 to 20°C. When the Tg of the acrylic resin is -50°C or higher, the tackiness of the die bonding film tends to be reduced, leading to improved handleability. When the Tg of the acrylic resin is 50°C or lower, the fluidity of the adhesive composition when forming the die bonding film tends to be more sufficiently ensured. Here, the glass transition temperature (Tg) of the (e) component refers to a value measured using a DSC (differential scanning calorimeter) (for example, Thermo Plus 2, product name, manufactured by Rigaku Corporation).

[0045] The weight average molecular weight (Mw) of the (e) component may be 50,000 to 1.6 million, 100,000 to 1.4 million, or 300,000 to 1.2 million. When the weight average molecular weight of the (e) component is 50,000 or more, the film-forming property tends to be more excellent. When the weight average molecular weight of the (e) component is 1.6 million or less, the flowability of the adhesive composition when forming a die bonding film tends to be more excellent. The weight average molecular weight (Mw) is a value measured by gel permeation chromatography (GPC) and converted using a calibration curve of standard polystyrene.

[0046] The measurement device, measurement conditions, etc. for the weight average molecular weight (Mw) of the component (e) are, for example, as follows: Pump: L-6000 (manufactured by Hitachi, Ltd.) Column: A column consisting of Gelpack GL-R440 (Hitachi Chemical Co., Ltd.), Gelpack GL-R450 (Hitachi Chemical Co., Ltd.), and Gelpack GL-R400M (Hitachi Chemical Co., Ltd.) (each 10.7 mm (diameter) × 300 mm) connected in this order. Eluent: tetrahydrofuran (hereinafter referred to as "THF") Sample: 120 mg of sample dissolved in 5 mL of THF Flow rate: 1.75mL / min

[0047] The content of component (e) may be 0.1 mass% or more, 0.3 mass% or more, 0.5 mass% or more, or 0.8 mass% or more, based on the total amount of the die bonding film, and may be 10 mass% or less, 8 mass% or less, 5 mass% or less, or 3 mass% or less.

[0048] The die bonding film 10 may further contain (f) a curing accelerator.

[0049] (f) Component: Curing accelerator By containing the (f) component, the die bonding film tends to be able to achieve both adhesiveness and connection reliability. Examples of the (f) component include imidazoles and their derivatives, 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, the (f) component may be imidazoles and their derivatives from the viewpoint of reactivity.

[0050] Examples of imidazoles include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, etc. These may be used alone or in combination of two or more.

[0051] The content of the component (f) may be 0.001 to 1 mass % based on the total amount of the die bonding film. When the content of the component (f) is in this range, there is a tendency that both adhesiveness and connection reliability can be more effectively achieved.

[0052] The die bonding film 10 may further contain, as other components in addition to the components (a) to (f), a coupling agent, an antioxidant, a rheology control agent, a leveling agent, etc. Examples of coupling agents include γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, etc. The content of the other components may be 0.01 to 3 mass% based on the total amount of the die bonding film.

[0053] The die bonding film 10 shown in FIG. 1 can be produced by forming an adhesive composition containing the above-mentioned components (a) and (b), and, if necessary, components (c) to (f) and other components, into a film. Such a die bonding film 10 can be formed by applying the adhesive composition to a support film 20. The adhesive composition can be used as an adhesive varnish diluted with a solvent. When an adhesive varnish is used, the adhesive varnish is applied to the support film 20, and the solvent is removed by heating and drying, thereby forming the die bonding film 10.

[0054] The solvent is not particularly limited as long as it can dissolve components other than the component (a). Examples of the solvent include aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, and p-cymene; aliphatic hydrocarbons such as hexane and heptane; cyclic alkanes such as methylcyclohexane; cyclic ethers such as tetrahydrofuran and 1,4-dioxane; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and 4-hydroxy-4-methyl-2-pentanone; esters such as methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, and γ-butyrolactone; carbonates such as ethylene carbonate and propylene carbonate; and amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone. These may be used alone or in combination of two or more. Among these, the solvent may be toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, or cyclohexanone from the viewpoints of solubility and boiling point. The solid component concentration in the adhesive varnish may be 10 to 80% by mass based on the total mass of the adhesive varnish.

[0055] The adhesive varnish can be prepared by mixing and kneading the components (a) to (f), other components, and a solvent. The order of mixing and kneading the components is not particularly limited and can be set appropriately. Mixing and kneading can be performed by appropriately combining a dispersing machine such as a normal stirrer, a grinding machine, a triple roll, a ball mill, or a bead mill. After preparing the adhesive varnish, air bubbles in the varnish can be removed by vacuum deaeration or the like.

[0056] The support film 20 is not particularly limited, and examples thereof include films of polytetrafluoroethylene, polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate, polyimide, etc. The support film may be subjected to a release treatment. The thickness of the support film 20 may be, for example, 10 to 200 μm or 20 to 170 μm.

[0057] The adhesive varnish can be applied to the support film 20 by a known method, such as knife coating, roll coating, spray coating, gravure coating, bar coating, curtain coating, etc. The conditions for heat drying are not particularly limited as long as the solvent used is sufficiently volatilized, and may be, for example, at 50 to 200° C. for 0.1 to 90 minutes.

[0058] The thickness of the die bonding film 10 can be appropriately adjusted depending on the application, and may be, for example, 3 to 200 μm. When the thickness of the die bonding film 10 is 3 μm or more, the adhesive strength with the semiconductor wafer tends to be sufficient, and when it is 200 μm or less, the heat dissipation tends to be sufficient. The thickness of the die bonding film 10 may be 5 to 100 μm or 10 to 50 μm from the viewpoints of adhesive strength and thinning of the semiconductor device.

[0059] In the die bonding film 10, the surface roughness of the first surface 10A may be, for example, 1.0 μm or less. Here, the first surface 10A is the surface placed on the adhesive layer of the dicing tape (i.e., the surface opposite to the surface of the die bonding film 10 in contact with the support film 20). In this specification, the surface roughness means the arithmetic mean roughness Ra (JIS B 0601-2001), and the arithmetic mean roughness Ra means a value calculated by the method described in the examples. The measurement magnification may be 50 to 100 times.

[0060] The surface roughness of the first surface 10A may be, for example, 0.9 μm or less, 0.8 μm or less, 0.7 μm or less, or 0.6 μm or less, from the viewpoint of preventing a decrease in adhesiveness due to the surface roughness. The surface roughness of the first surface 10A may be, for example, 0.1 μm or more, 0.2 μm or more, or 0.3 μm or more, from the viewpoint of preventing a decrease in anchor effect due to an excessively high surface smoothness.

[0061] The die bonding film of the present disclosure is considered to have excellent heat dissipation properties because the (b) component sufficiently reduces and removes the oxide layer (oxide film) on the surface of the (a) component and maintains this state. Therefore, the die bonding film of the present disclosure can be suitably used as a dicing / die bonding integrated film in combination with a dicing tape having an adhesive layer.

[0062] [Dicing and die bonding integrated film] 2 is a schematic cross-sectional view showing one embodiment of a dicing-die bonding integrated film. The dicing-die bonding integrated film 100 shown in FIG. 2 includes a dicing tape 50 having a substrate 40 and an adhesive layer 30 provided on the substrate 40, and a die bonding film 10 arranged on the adhesive layer 30 of the dicing tape 50. The die bonding film 10 has a first surface 10A and a second surface 10B opposite to the first surface 10A. The dicing-die bonding integrated film 100 may include a support film 20 on the second surface 10B of the die bonding film 10.

[0063] Examples of the substrate 40 in the dicing tape 50 include plastic films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. Furthermore, the substrate 40 may be subjected to a surface treatment such as primer coating, UV treatment, corona discharge treatment, polishing treatment, and etching treatment, as necessary.

[0064] The adhesive layer 30 may be an adhesive layer made of an adhesive used in the field of dicing tapes, and may be an adhesive layer made of a pressure-sensitive adhesive or an adhesive layer made of an ultraviolet-curing adhesive. When the adhesive layer 30 is an adhesive layer made of an ultraviolet-curing adhesive, the adhesive layer 30 may have a property of decreasing adhesiveness by irradiation with ultraviolet rays.

[0065] The dicing / die bonding integrated film 100 can be produced by preparing a dicing tape 50 and a die bonding film 10 , and attaching the first surface 10 A of the die bonding film 10 to the adhesive layer 30 of the dicing tape 50 .

[0066] In the dicing / die bonding integrated film 100, the die bonding film 10 contains 75 mass % or more of the component (a) based on the total amount of the die bonding film. The dicing / die bonding integrated film having such an adhesive layer and an adhesive layer can have excellent heat dissipation properties.

[0067] [Manufacturing method for semiconductor device (semiconductor package)] 3A, 3B, 3C, 3D, 3E, and 3F are schematic cross-sectional views showing one embodiment of a method for manufacturing a semiconductor device, in which (a), (b), (c), (d), (e), and (f) are schematic cross-sectional views showing each step. The method for manufacturing a semiconductor device includes a step of attaching the die bonding film 10 (adhesive layer) (the second surface 10B) of the above-mentioned dicing-die bonding integrated film 100 to a semiconductor wafer W (wafer lamination step, see Figures 3(a) and (b)), a step of dividing the semiconductor wafer W and the die bonding film 10 (adhesive layer) (dicing step, see Figure 3(c)), a step of irradiating the adhesive layer 30 (through the substrate 40) with ultraviolet light as necessary (ultraviolet light irradiation step, see Figure 3(d)), a step of picking up the semiconductor chip Wa (semiconductor chip 60 with adhesive piece) to which the die bonding film piece 10a is attached from the adhesive layer 30a (pickup step, see Figure 3(e)), and a step of adhering the semiconductor chip 60 with adhesive piece to a support substrate 80 through the die bonding film piece 10a (semiconductor chip adhering step, see Figure 3(f)).

[0068] <Wafer lamination process> First, the dicing / die bonding integrated film 100 is placed in a predetermined device. Then, the second surface 10B of the die bonding film 10 (adhesive layer) of the dicing / die bonding integrated film 100 is attached to the surface Ws of the semiconductor wafer W (see FIGS. 3(a) and 3(b)). The circuit surface of the semiconductor wafer W is preferably provided on the surface opposite to the surface Ws.

[0069] <Dicing process> Next, the semiconductor wafer W and the die bonding film 10 (adhesive layer) are diced (see FIG. 3(c)). At this time, a part of the adhesive layer 30, or the entire adhesive layer 30 and a part of the base material 40 may be diced. In this manner, the dicing / die bonding integrated film 100 also functions as a dicing sheet.

[0070] <Ultraviolet irradiation process> Next, as necessary, the adhesive layer 30 is irradiated with ultraviolet light (through the substrate 40) (see FIG. 3(d)). This cures the adhesive layer 30, and the adhesive strength between the adhesive layer 30 and the die bonding film 10 (adhesive layer) can be sufficiently reduced. For ultraviolet light irradiation, it is preferable to use ultraviolet light with a wavelength of 200 to 400 nm. The ultraviolet light irradiation conditions are an illuminance and an irradiation amount of 30 to 240 mW / cm, respectively. 2 range and 50~500mJ / cm 2 It is preferable to adjust the range to be within the range of 100 to 200 mm.

[0071] <Pickup process> Next, the substrate 40 is expanded to separate the diced semiconductor chips 60 with adhesive pieces from each other, while the semiconductor chips 60 with adhesive pieces pushed up by the needles 72 from the substrate 40 side are sucked by the suction collet 74 to be picked up from the adhesive layer 30a (see FIG. 3(e)). The semiconductor chips 60 with adhesive pieces have a semiconductor chip Wa and a die bonding film piece 10a. The semiconductor chip Wa is obtained by dicing the semiconductor wafer W into individual pieces, and the die bonding film piece 10a is obtained by dicing the die bonding film 10 into individual pieces. The adhesive layer 30a is obtained by dicing the adhesive layer 30 into individual pieces. The adhesive layer 30a may remain on the substrate 40 when the semiconductor chips 60 with adhesive pieces are picked up. In the pick-up process, it is not necessarily necessary to expand the substrate 40, but by expanding the substrate 40, the pick-up property can be further improved.

[0072] The amount of push-up by the needle 72 can be set appropriately. Furthermore, from the viewpoint of ensuring sufficient pick-up performance even for an extremely thin wafer, for example, two-stage or three-stage push-up may be performed. Furthermore, the semiconductor chip 60 with the adhesive piece attached may be picked up by a method other than the method using the suction collet 74.

[0073] <Semiconductor chip bonding process> After picking up the semiconductor chip 60 with the adhesive piece, the semiconductor chip 60 with the adhesive piece is bonded to the support substrate 80 via the die bonding film piece 10a by thermocompression bonding (see FIG. 3(f)). A plurality of semiconductor chips 60 with adhesive pieces may be bonded to the support substrate 80.

[0074] The method for manufacturing a semiconductor device may further include, as necessary, a step of electrically connecting the semiconductor chip Wa and the support substrate 80 by wire bonding, and a step of resin-sealing the semiconductor chip Wa on the surface 80A of the support substrate 80 using a resin sealing material.

[0075] Fig. 4 is a schematic cross-sectional view showing one embodiment of a semiconductor device. The semiconductor device 200 shown in Fig. 4 can be manufactured through the above-mentioned steps. In the semiconductor device 200, the semiconductor chip Wa and the support substrate 80 may be electrically connected by wire bonds 70. In the semiconductor device 200, the semiconductor chip Wa may be resin-encapsulated on the front surface 80A of the support substrate 80 using a resin encapsulant 92. Solder balls 94 may be formed on the surface of the support substrate 80 opposite to the front surface 80A for electrical connection with an external substrate (motherboard). EXAMPLES

[0076] The present disclosure will be described below with reference to examples, but the present disclosure is not limited to these examples.

[0077] <Preparation of adhesive varnish> Cyclohexanone was added to (c) epoxy resin as a thermosetting resin, (d) phenolic resin as a curing agent, and (e) acrylic rubber as an elastomer, with the symbols and composition ratios (unit: parts by mass) shown in Table 1, and the mixture was stirred to obtain a mixture. After each component was dissolved, (a) silver-containing particles having an oxide layer on the surface were added to the mixture, and the mixture was stirred using a dispersing blade to disperse each component until it was uniform. Then, (f) a curing accelerator was added, and each component was dispersed until it was uniform, to obtain adhesive varnishes A to G with a solid content of 78% by mass.

[0078] The symbols for each component in Table 1 represent the following products.

[0079] (a) Silver-containing particles having an oxide layer on the surface Ag-HWQ1.5μm (product name, silver particles produced by atomization method, manufactured by Fukuda Metal Foil and Powder Co., Ltd., shape: spherical, average particle size (laser 50% particle size (D 50 )):1.0~2.0μm)

[0080] (b) Fluxing agent Glutaric acid (manufactured by Fujifilm Wako Pure Chemical Industries, molecular weight: 132.1) Benzilic acid (Tokyo Chemical Industry Co., Ltd., aromatic carboxylic acid, molecular weight: 228.3)

[0081] (c) Thermosetting resin EXA-830CRP (product name, manufactured by DIC Corporation, bisphenol type epoxy resin, epoxy equivalent: 159g / eq, liquid at 25℃)

[0082] (d) Hardener MEH-7800M (product name, manufactured by Meiwa Kasei Co., Ltd., phenolic resin, viscosity (150°C): 0.31-0.43 Pa·s (3.1-4.3 poise), hydroxyl equivalent: 175 g / eq)

[0083] (e) Elastomer HTR-860P-3CSP (product name, Nagase ChemteX Corporation, acrylic rubber, weight average molecular weight: 1 million, Tg: -7℃) SG-280 EK23 (product name, Nagase ChemteX Corporation, acrylic rubber, weight average molecular weight: 900,000, Tg: -29°C)

[0084] (f) Curing accelerator 2PZ-CN (product name, Shikoku Chemical Industry Co., Ltd., 1-cyanoethyl-2-phenylimidazole)

[0085] [Table 1]

[0086] Example 1 <Preparation of die bonding film> Adhesive varnish A was used to prepare the die bonding film. The adhesive varnish A, which had been vacuum degassed, was applied onto a polyethylene terephthalate (PET) film (thickness 38 μm) that had been subjected to a release treatment, which was a support film. The applied varnish was heated and dried in two stages, at 90° C. for 5 minutes and then at 130° C. for 5 minutes, to prepare a die bonding film of Example 1 having a thickness of 20 μm in a B-stage state on the support film.

[0087] <Measurement of thermal conductivity> (Preparation of film for measuring thermal conductivity) A laminated film having a thickness of 100 μm or more was prepared by laminating a plurality of the die bonding films of Example 1 with a rubber roll. The laminated film obtained was covered on both sides with PET films and heat cured at 110° C. for 1 hour and then at 170° C. for 3 hours to obtain a film for measuring thermal conductivity.

[0088] (Measurement of thermal conductivity) The thermal conductivity of the film for measuring thermal conductivity was calculated by the following formula. The results are shown in Table 2. Thermal conductivity (W / m K) = Thermal diffusivity α (mm 2 / s) × specific heat Cp (J / g K) × specific gravity (g / cm3 ) The thermal diffusivity α, specific heat Cp, and specific gravity were measured by the following methods. Higher thermal conductivity means better heat dissipation properties.

[0089] (Measurement of thermal diffusivity α) The thermal conductivity measurement film obtained above was cut into 10 mm squares. Blackguard spray (FC-153, Fine Chemical Japan Co., Ltd.) was applied to both sides of the cut thermal conductivity measurement film to prepare a measurement sample. A flash analyzer (LFA467 HyperFlash, Netsch Japan Co., Ltd.) was used to measure the thermal diffusivity α at 35°C.

[0090] (Measurement of specific heat Cp) Using a differential scanning calorimeter (DSC) (high sensitivity differential scanning calorimeter DSC8231 (manufactured by Rigaku Corporation)), measurements were taken at a temperature rise rate of 10°C / min at temperatures of 25°C to 70°C to calculate the specific heat Cp at 35°C.

[0091] (Measurement of specific gravity) The measurement was performed by the Archimedes method using an electronic specific gravity meter (EW-300SG, manufactured by Alpha Mirage Co., Ltd.).

[0092] <Production of integrated dicing and die bonding tape> A dicing tape having a substrate and an adhesive layer (product name: 6363-30, manufactured by Hitachi Chemical Co., Ltd.) was prepared, and the adhesive layer of the dicing tape was bonded to the die bonding film of Example 1 with a rubber roll to produce the integrated dicing and die bonding tape of Example 1 having the substrate, adhesive layer, and adhesive layer (die bonding film) in that order.

[0093] <Measurement of T-peel strength between adhesive layer and adhesive layer before and after UV irradiation> The integrated dicing and die bonding tape of Example 1 was prepared and used to measure the T-peel strength between the adhesive layer and the adhesive layer. An Autograph EZ-S 50N (manufactured by Shimadzu Corporation) was used for the measurement. An easy-cut tape (manufactured by Oji Tack Co., Ltd.) was attached to the adhesive layer (die bonding film) side of the integrated dicing and die bonding tape, and the integrated dicing and die bonding tape was cut into a size of 25 mm wide and 100 mm long to obtain a sample. Using this sample, the T-peel strength between the adhesive layer and the adhesive layer was measured before and after ultraviolet irradiation at a chuck distance of 50 mm and a speed of 300 mm / min. The ultraviolet irradiation was performed with a halogen lamp at 80 mW / cm. 2 , 200mJ / cm 2 The measurements were carried out three times before and three times after UV irradiation, and the average value of the three measurements was taken as the peel strength. The results are shown in Table 2.

[0094] Example 2 Except for using adhesive varnish B to prepare the die bonding film, the die bonding film and the integrated dicing / die bonding tape of Example 2 were obtained in the same manner as in Example 1. The thermal conductivity and the T-peel strength between the adhesive layer and the adhesive layer before and after ultraviolet irradiation were measured for the die bonding film and the integrated dicing / die bonding tape of Example 2 in the same manner as in Example 1. The results are shown in Table 2.

[0095] Example 3 Except for using adhesive varnish C to prepare the die bonding film, the die bonding film and the integrated dicing / die bonding tape of Example 3 were obtained in the same manner as in Example 1. The thermal conductivity and the T-peel strength between the adhesive layer and the adhesive layer before and after ultraviolet irradiation were measured for the die bonding film and the integrated dicing / die bonding tape of Example 3 in the same manner as in Example 1. The results are shown in Table 2.

[0096] Example 4 Except for using adhesive varnish D to prepare the die bonding film, the die bonding film and the integrated dicing / die bonding tape of Example 4 were obtained in the same manner as in Example 1. The thermal conductivity and the T-peel strength between the adhesive layer and the adhesive layer before and after ultraviolet irradiation were measured for the die bonding film and the integrated dicing / die bonding tape of Example 4 in the same manner as in Example 1. The results are shown in Table 2.

[0097] Example 5 Except for using adhesive varnish E to prepare the die bonding film, the die bonding film and the integrated dicing / die bonding tape of Example 5 were obtained in the same manner as in Example 1. The thermal conductivity and the T-peel strength between the adhesive layer and the adhesive layer before and after ultraviolet irradiation were measured for the die bonding film and the integrated dicing / die bonding tape of Example 5 in the same manner as in Example 1. The results are shown in Table 2.

[0098] Example 6 Except for using adhesive varnish F to prepare the die bonding film, the die bonding film and the integrated dicing / die bonding tape of Example 6 were obtained in the same manner as in Example 1. The thermal conductivity and the T-peel strength between the adhesive layer and the adhesive layer before and after ultraviolet irradiation were measured for the die bonding film and the integrated dicing / die bonding tape of Example 6 in the same manner as in Example 1. The results are shown in Table 2.

[0099] Comparative Example 1 A die bonding film and a dicing / die bonding integrated tape of Comparative Example 1 were obtained in the same manner as in Example 1, except that adhesive varnish G was used to prepare the die bonding film. The thermal conductivity of the die bonding film of Comparative Example 1 was measured in the same manner as in Example 1. The results are shown in Table 2. Note that, since the thermal conductivity of the die bonding film of Comparative Example 1 was insufficient, the T-peel strength between the adhesive layer and the adhesive layer of the dicing / die bonding integrated tape of Comparative Example 1 was not measured before and after ultraviolet irradiation. The results are shown in Table 2.

[0100] [Table 2]

[0101] As shown in Table 2, the integrated dicing and die bonding tapes of Examples 1 to 6, which contained a flux agent, had superior thermal conductivity compared to the integrated dicing and die bonding tape of Comparative Example 1, which did not contain a flux agent. It was also found that the integrated dicing and die bonding tapes of Examples 5 and 6, which contained benzilic acid, were able to reduce the T-peel strength after ultraviolet irradiation compared to the T-peel strength before ultraviolet irradiation. These results confirmed that the integrated dicing and die bonding film of the present disclosure has excellent heat dissipation properties. [Explanation of symbols]

[0102] 10...die bonding film, 10A...first surface, 10B...second surface, 10a...die bonding film piece, 20...support film, 30...adhesive layer, 40...substrate, 50...dicing tape, 60...semiconductor chip with adhesive piece, 70...wire bond, 72...needle, 74...suction collet, 80...support substrate, 92...resin encapsulant, 94...solder ball, 100...dicing and die bonding integrated film, 200...semiconductor device.

Claims

1. a dicing tape having a substrate and an adhesive layer provided on the substrate; a die bonding film disposed on the adhesive layer of the dicing tape; Equipped with The die bonding film contains silver-containing particles having an oxide layer on a surface thereof, a fluxing agent, a thermosetting resin, and an elastomer; The content of the silver-containing particles is 75 mass% or more based on the total amount of the die bonding film. Integrated dicing and die bonding film.

2. The fluxing agent is an aromatic carboxylic acid.

2. The dicing and die bonding integrated film according to claim 1.

3. The die bonding film further contains a curing agent.

3. The dicing and die bonding integrated film according to claim 1 or 2.

4. The thermosetting resin contains an epoxy resin that is liquid at 25°C. The dicing and die bonding integrated film according to claim 3 .

5. A step of attaching the die bonding film of the dicing and die bonding integrated film according to any one of claims 1 to 4 to a semiconductor wafer; singulating the semiconductor wafer and the die bonding film; picking up the semiconductor chip having the die bonding film piece attached thereto from the dicing tape; bonding the semiconductor chip to a support substrate via the die bonding film piece; Equipped with A method for manufacturing a semiconductor device.

6. The method further includes a step of irradiating the adhesive layer with ultraviolet light after the step of singulating the semiconductor wafer and the die bonding film. The method for manufacturing a semiconductor device according to claim 5 .

7. The present invention comprises silver-containing particles having an oxide layer on the surface thereof, a fluxing agent, a thermosetting resin, and an elastomer, The content of the silver-containing particles is 75 mass% or more based on the total amount of the die bonding film. Die bonding film.

8. The fluxing agent is an aromatic carboxylic acid. The die bonding film according to claim 7 .

9. Further containing a curing agent. The die bonding film according to claim 7 or 8.

10. The thermosetting resin contains an epoxy resin that is liquid at 25°C. The die bonding film according to claim 9 .

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