WO2020129996A1 - Adhésif sous forme de film, feuille adhésive, et dispositif à semi-conducteur et son procédé de fabrication - Google Patents

Adhésif sous forme de film, feuille adhésive, et dispositif à semi-conducteur et son procédé de fabrication Download PDF

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Publication number
WO2020129996A1
WO2020129996A1 PCT/JP2019/049478 JP2019049478W WO2020129996A1 WO 2020129996 A1 WO2020129996 A1 WO 2020129996A1 JP 2019049478 W JP2019049478 W JP 2019049478W WO 2020129996 A1 WO2020129996 A1 WO 2020129996A1
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WIPO (PCT)
Prior art keywords
adhesive
film
film adhesive
semiconductor element
semiconductor
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PCT/JP2019/049478
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English (en)
Japanese (ja)
Inventor
慎太郎 橋本
由衣 國土
奏美 中村
恒則 大平
紘平 谷口
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日立化成株式会社
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Publication of WO2020129996A1 publication Critical patent/WO2020129996A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
    • C09J11/02—Non-macromolecular additives
    • C09J11/04—Non-macromolecular additives inorganic
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
    • C09J11/08—Macromolecular additives
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J163/00—Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
    • C09J7/35—Heat-activated

Definitions

  • the present invention relates to a film adhesive, an adhesive sheet, a semiconductor device and a method for manufacturing the same.
  • stacked MCPs Multi Chip Packages
  • semiconductor elements semiconductor elements (semiconductor chips) are stacked in multiple stages
  • memory semiconductor packages for mobile phones and mobile audio devices.
  • higher speed, higher density, and higher integration of semiconductor packages are being promoted.
  • the speed has been increased by using copper as a wiring material for semiconductor chip circuits.
  • lead frames made of copper are being used.
  • the semiconductor package is electrically conductive. It tends to be difficult to secure the desired characteristics.
  • copper ions generated by corrosion move inside the adhesive, and electrical signal loss tends to occur within the semiconductor chip or between semiconductor chips/semiconductor chips.
  • Adhesives that capture copper ions generated in semiconductor packages are being studied from the viewpoint of preventing loss of electrical signals.
  • a thermoplastic resin having an epoxy group and not having a carboxyl group and a heterocyclic compound containing a tertiary nitrogen atom as a ring atom are formed, and a complex is formed with a cation.
  • an adhesive sheet for producing a semiconductor device which comprises the organic complex forming compound.
  • the present invention is mainly intended to provide a film-like adhesive that can sufficiently suppress the problems associated with the movement of copper ions in the adhesive and that is excellent in the adhesiveness and embedding property with the substrate.
  • One aspect of the present invention provides a film adhesive for adhering a semiconductor element and a supporting member on which the semiconductor element is mounted.
  • the film adhesive contains an epoxy resin having an epoxy equivalent of 140 to 220 g/eq, a phenol resin having a hydroxyl equivalent of 90 to 130 g/eq, and a thermoplastic resin, and the content of the thermoplastic resin is , 55 to 75 mass% based on the total amount of the film adhesive.
  • the crosslink density of the cured product of the film adhesive tends to increase.
  • the adhesiveness with the substrate is improved, and further, it is possible to suppress the incorporation of copper ions and the like from the outside, and as a result, the adhesive It is possible to sufficiently suppress the problems associated with the movement of copper ions inside.
  • the film adhesive can improve the embedding property even after undergoing a thermal history by containing a specific content of the thermoplastic resin, resulting in peeling at the adhesive interface and insufficient embedding property of the substrate. It is possible to suppress defects.
  • the thermoplastic resin may be an acrylic resin.
  • the acrylic resin may contain a specific acrylic resin.
  • P CO the height of the absorption peak derived from the stretching vibration of the carbonyl group
  • P CN the height of the peak derived from the stretching vibration of the nitrile group
  • the acrylic resin may satisfy the condition of the following formula (1). P CN /P CO ⁇ 0.100 (1)
  • the film adhesive may further contain an inorganic filler.
  • the thickness of the film adhesive may be 50 ⁇ m or less.
  • the adhesive sheet includes a base material and the above film adhesive provided on one surface of the base material.
  • the substrate may be a dicing tape.
  • the semiconductor device includes a semiconductor element, a support member on which the semiconductor element is mounted, and an adhesive member that is provided between the semiconductor element and the support member and adheres the semiconductor element and the support member, and the adhesive member is the above-mentioned member. It is a cured product of a film adhesive.
  • the support member may include a member made of copper.
  • Another aspect of the present invention provides a method for manufacturing a semiconductor device.
  • One aspect of a method for manufacturing a semiconductor device includes a step of adhering a semiconductor element and a supporting member using the above film adhesive.
  • Another aspect of a method for manufacturing a semiconductor device is to attach a plurality of pieces of a plurality of pieces by cutting the semiconductor wafer on which the film-like adhesive of the above-mentioned adhesive sheet is attached to the semiconductor wafer and the step of attaching the film-like adhesive.
  • the method includes a step of producing a semiconductor element with a film-like adhesive and a step of adhering the semiconductor element with a film-like adhesive to a support member.
  • the method for manufacturing the semiconductor device may further include a step of heating the semiconductor element with the film adhesive attached to the support member using a reflow oven.
  • a film-like adhesive that can sufficiently suppress defects caused by the movement of copper ions in the adhesive, and that is excellent in adhesiveness and embeddability with a substrate.
  • an adhesive sheet and a semiconductor device using such a film adhesive are provided.
  • a method for manufacturing a semiconductor device using a film adhesive or an adhesive sheet is provided.
  • the numerical range indicated by using “to” indicates the range including the numerical values before and after “to” as the minimum value and the maximum value, respectively.
  • the upper limit or the lower limit described in one numerical range may be replaced with the upper limit or the lower limit of the numerical range described in other stages. Good.
  • the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
  • (meth)acrylate means acrylate or corresponding methacrylate.
  • the film adhesive is a film adhesive for adhering a semiconductor element and a supporting member on which the semiconductor element is mounted, and is (A) an epoxy resin having an epoxy equivalent of 140 to 220 g/eq. (Hereinafter, sometimes referred to as "specific epoxy resin"), and (B) a phenol resin having a hydroxyl equivalent of 90 to 130 g/eq (hereinafter sometimes referred to as "specific phenol resin"), and ( C) and a thermoplastic resin.
  • the content of the thermoplastic resin is 55 to 75 mass% based on the total amount of the film adhesive.
  • the film adhesive can be obtained by molding an adhesive composition containing (A) a specific epoxy resin, (B) a specific phenol resin, and (C) a thermoplastic resin into a film. it can.
  • the film adhesive and the adhesive composition may be those that can go through a semi-cured (B stage) state and then a fully cured (C stage) state after the curing treatment.
  • Component (A) Epoxy resin having an epoxy equivalent of 140 to 220 g/eq.
  • the component (A) is not particularly limited as long as it has an epoxy equivalent of 140 to 220 g/eq and has an epoxy group in the molecule. Can be used.
  • Examples of such component (A) include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol.
  • F novolac type epoxy resin stilbene type epoxy resin, triazine skeleton containing epoxy resin, fluorene skeleton containing epoxy resin, triphenol methane type epoxy resin, biphenyl type epoxy resin, xylylene type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin , Polyfunctional phenols, diglycidyl ether compounds of polycyclic aromatic compounds such as anthracene, and the like. These may be used alone or in combination of two or more.
  • the component (A) may be a cresol novolac type epoxy resin, a phenol novolac type epoxy resin, a bisphenol F type epoxy resin, or a bisphenol A type epoxy resin from the viewpoint of tackiness and flexibility of the film. Good.
  • the epoxy equivalent of the epoxy resin is 140 to 220 g/eq.
  • the epoxy equivalent of the epoxy resin may be 145 to 215 g/eq or 150 to 210 g/eq.
  • the epoxy equivalent of the epoxy resin is in such a range, when it is combined with a specific phenol resin, the cured product of the obtained film adhesive tends to have a high crosslinking density.
  • Component (B) Phenolic resin having a hydroxyl equivalent of 90 to 130 g/eq.
  • Component (B) can be a curing agent for epoxy resins.
  • Component (B) can be used without particular limitation as long as it has a hydroxyl equivalent of 90 to 130 g/eq and has a phenolic hydroxyl group in the molecule.
  • examples of the component (B) include phenols such as phenol, cresol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol and aminophenol, and/or ⁇ -naphthol, ⁇ -naphthol, dihydroxynaphthalene and the like.
  • novolac type phenol resins obtained by condensation or cocondensation of naphthols and a compound having an aldehyde group such as formaldehyde under an acidic catalyst. These may be used alone or in combination of two or more.
  • the component (B) may be a phenol novolac type phenol resin or a naphthol aralkyl resin.
  • the hydroxyl equivalent of the phenol resin is 90 to 130 g/eq.
  • the hydroxyl equivalent of the phenol resin may be 95 to 125 g/eq or 100 to 120 g/eq. If the hydroxyl equivalent of the phenolic resin is 70 g/eq or more, the crosslink density of the cured product of the obtained film adhesive tends to be high when combined with a specific epoxy resin.
  • the ratio of the epoxy equivalent of the component (A) to the hydroxyl equivalent of the component (B) is 0.30/0.70. ⁇ 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 It may be 0.55/0.45.
  • the equivalent ratio is 0.30/0.70 or more, more sufficient curability tends to be obtained.
  • the equivalent ratio is 0.70/0.30 or less, it is possible to prevent the viscosity from becoming too high, and it is possible to obtain more sufficient fluidity.
  • the total content of the components (A) and (B) may be 5 to 45% by mass, 10 to 40% by mass, or 15 to 30% by mass based on the total amount of the film adhesive.
  • the elastic modulus tends to be improved by crosslinking.
  • the total content of the component (A) and the component (B) is 45% by mass or less based on the total amount of the film adhesive, the film handleability tends to be maintained.
  • Thermoplastic Resin examples include acrylic resins, polyester resins, polyamide resins, polyimide resins, silicone resins, butadiene resins; and modified products thereof. These may be used alone or in combination of two or more.
  • the component (C) may be an acrylic resin from the viewpoint of having few ionic impurities, high heat resistance, and ensuring the reliability of the semiconductor element.
  • the acrylic resin means a polymer having a structural unit derived from a (meth)acrylic acid ester.
  • the acrylic resin 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, and a carboxyl group.
  • the acrylic resin may be an acrylic rubber having a structural unit derived from a (meth)acrylic acid ester as a main component.
  • the content of the structural unit derived from the (meth)acrylic acid ester in the acrylic rubber 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 unit.
  • the 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, and a carboxyl group.
  • the acrylic resin is capable of further suppressing the movement of copper ions in the adhesive by reducing the nitrile group contained in the acrylic resin, and also has an embedding property. Tends to be better. Therefore, the acrylic resin may contain an acrylic resin having a low proportion of nitrile groups, or may contain an acrylic resin containing no nitrile groups (that is, an acrylic resin containing no structural unit derived from acrylonitrile). ..
  • the acrylic resin has the following formula (1), where P CO is the height of the absorption peak derived from the stretching vibration of the carbonyl group and P CN is the height of the peak derived from the stretching vibration of the nitrile group. ) Acrylic resin satisfying the condition of 1) may be included. P CN /P CO ⁇ 0.100 (1)
  • the carbonyl group is mainly derived from the structural unit (meth)acrylic acid ester
  • the nitrile group is mainly derived from the structural unit acrylonitrile.
  • the height of the absorption peak derived from the stretching vibration of the carbonyl group (P CO ) and the height of the peak derived from the stretching vibration of the nitrile group (P CN ) are defined in the examples.
  • a small P CN /P CO means that the acrylic resin has a small number of structural units derived from acrylonitrile. Therefore, an acrylic resin that does not include a structural unit derived from acrylonitrile theoretically has a numerical value of P CN /P CO close to 0 and can satisfy the condition of the formula (1).
  • P CN / P CO may be 0.100 or less, 0.095 or less, 0.090 or less, 0.085 or less, 0.080 or less, 0.075 or less, 0.070 or less, 0.065 or less , 0.060 or less, 0.055 or less, 0.050 or less, 0.040 or less, 0.030 or less, 0.020 or less, or 0.010 or less.
  • P CN /P CO 0.100 or less, it may be possible to sufficiently suppress the movement (permeation) of copper ions in the adhesive. Further, it is possible as the value of P CN / P CO decreases, more sufficiently suppressed migration of copper ions in the adhesive (transparent). Also, as the value of P CN / P CO is reduced, to lower the cohesive force of the acrylic resin tends to be buried resistance more excellent.
  • the acrylic resin two or more kinds of acrylic resins satisfying such requirements may be used in combination.
  • the glass transition temperature (Tg) of the component (C) may be -50 to 50°C or -30 to 30°C.
  • Tg of the component (C) is ⁇ 50° C. or higher, it tends to be possible to prevent the flexibility of the adhesive from becoming too high. As a result, the film adhesive can be easily cut during wafer dicing, and burrs can be prevented from occurring.
  • the Tg of the component (C) is 50° C. or less, the flexibility of the adhesive tends to be suppressed from decreasing. This tends to make it easier to fill voids when the film adhesive is attached to the wafer. In addition, it becomes possible to prevent chipping at the time of dicing due to deterioration of the adhesiveness of the wafer.
  • the glass transition temperature (Tg) means a value measured using DSC (Thermal Differential Scanning Calorimeter) (for example, Thermo Plus 2 manufactured by Rigaku Corporation).
  • the weight average molecular weight (Mw) of the component (C) may be 100,000 to 3,000,000 or 200,000 to 2,000,000.
  • Mw means a value measured by gel permeation chromatography (GPC) and converted using a calibration curve based on standard polystyrene.
  • Examples of commercially available products of the component (C) (acrylic rubber) include SG-P3, SG-80H, HTR-860P-3CSP (all manufactured by Nagase ChemteX Corporation).
  • Examples of commercially available products of component (C) (acrylic rubber) that does not contain a structural unit derived from acrylonitrile include KH-CT-865 (manufactured by Hitachi Chemical Co., Ltd.).
  • the content of the component (C) is 55 to 75 mass% based on the total amount of the film adhesive, and may be 57 mass% or more or 60 mass% or more, and 73 mass% or less or 70 mass% or less. You can When the content of the component (C) is 55% by mass or more based on the total amount of the film adhesive, the embedding property after the heat history is applied tends to be improved. When the content of the component (C) is 75% by mass or less based on the total amount of the film adhesive, sufficient adhesiveness tends to be secured.
  • Component (D) Inorganic filler
  • the film adhesive may further contain (D) an inorganic filler.
  • the component (D) include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, and boron nitride. , Silica and the like. These may be used alone or in combination of two or more. These may be surface-treated with a surface treatment agent such as a silane coupling agent. Among these, the component (D) may be silica from the viewpoint of adjusting the melt viscosity.
  • the shape of the component (D) is not particularly limited, but may be spherical.
  • the average particle size of the component (D) may be 0.01 to 1 ⁇ m, 0.01 to 0.08 ⁇ m, or 0.03 to 0.06 ⁇ m from the viewpoint of fluidity.
  • the average particle diameter means a value obtained by converting from the BET specific surface area.
  • the content of the component (D) may be 0.1 to 50% by mass, 0.1 to 30% by mass, or 0.1 to 20% by mass based on the total amount of the film adhesive.
  • the film adhesive may further contain (E) a coupling agent, (F) a curing accelerator and the like.
  • the component (E) may be a silane coupling agent.
  • the silane coupling agent include ⁇ -ureidopropyltriethoxysilane, ⁇ -mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, and 3-(2-aminoethyl)aminopropyltrimethoxysilane. To be These may be used alone or in combination of two or more.
  • Component (F) Curing Accelerator
  • the component (F) is not particularly limited, and those generally used can be used.
  • Examples of the component (F) 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.
  • the component (F) may be an imidazole or a derivative thereof from the viewpoint of reactivity.
  • imidazoles examples include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole and the like. These may be used alone or in combination of two or more.
  • the film adhesive may further contain other components.
  • Other components include, for example, pigments, ion scavengers, antioxidants and the like.
  • the content of the component (E), the component (F), and other components may be 0 to 30 mass% based on the total amount of the film adhesive.
  • FIG. 1 is a schematic cross-sectional view showing an embodiment of a film adhesive.
  • the film adhesive 1 (adhesive film) shown in FIG. 1 is obtained by molding an adhesive composition into a film.
  • the film adhesive 1 may be in a semi-cured (B stage) state.
  • Such a film adhesive 1 can be formed by applying an adhesive composition to a support film.
  • the varnish of the adhesive composition adheresive varnish
  • the components (A) and (B), and other components that are added as necessary are mixed in a solvent, and the mixed liquid is mixed or kneaded.
  • the adhesive varnish is prepared, the adhesive varnish is applied to the support film, and the solvent is heated and dried to remove the adhesive to form the film adhesive 1.
  • the support film is not particularly limited as long as it can withstand the above heat drying, for example, polyester film, polypropylene film, polyethylene terephthalate film, polyimide film, polyetherimide film, polyether naphthalate film, polymethylpentene film, etc. May be
  • the base material 2 may be a multilayer film in which two or more kinds are combined, and the surface thereof may be treated with a release agent such as a silicone-based or silica-based release agent.
  • the thickness of the support film may be, for example, 10 to 200 ⁇ m or 20 to 170 ⁇ m.
  • Mixing or kneading can be performed using a disperser such as an ordinary stirrer, raider, triple roll, ball mill and the like. You may combine these suitably.
  • a disperser such as an ordinary stirrer, raider, triple roll, ball mill and the like. You may combine these suitably.
  • 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.
  • a solvent include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, toluene, xylene, and the like.
  • the solvent may be methyl ethyl ketone, cyclohexanone or the like in terms of drying speed and price.
  • a known method can be used, and examples thereof include a knife coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, and a curtain coating method.
  • the heating and drying conditions are not particularly limited as long as the solvent used is sufficiently volatilized, but heating and drying can be performed at 50 to 150° C. for 1 to 30 minutes.
  • the thickness of the film adhesive may be 50 ⁇ m or less.
  • the thickness of the film adhesive may be 40 ⁇ m or less, 30 ⁇ m or less, 20 ⁇ m or less, or 15 ⁇ m or less.
  • the lower limit of the thickness of the film adhesive 1 is not particularly limited, but can be, for example, 1 ⁇ m or more.
  • FIG. 2 is a schematic cross-sectional view showing an embodiment of the adhesive sheet.
  • the adhesive sheet 100 shown in FIG. 2 includes a base material 2 and a film adhesive 1 provided on the base material 2.
  • FIG. 3 is a schematic cross-sectional view showing another embodiment of the adhesive sheet.
  • the adhesive sheet 110 shown in FIG. 3 includes a base material 2, a film adhesive 1 provided on the base material 2, and a cover film provided on the surface of the film adhesive 1 opposite to the base material 2. 3 and 3.
  • the base material 2 is not particularly limited, but may be a base material film.
  • the base film may be similar to the support film described above.
  • the cover film 3 is used to prevent damage or contamination of the film adhesive, and may be, for example, a polyethylene film, a polypropylene film, a surface release agent-treated film, or the like.
  • the thickness of the cover film 3 may be, for example, 15 to 200 ⁇ m or 70 to 170 ⁇ m.
  • the adhesive sheets 100 and 110 can be formed by applying an adhesive composition to a base film, similarly to the method of forming a film adhesive described above.
  • the method of applying the adhesive composition to the substrate 2 may be the same as the method of applying the adhesive composition to the support film.
  • the adhesive sheet 110 can be obtained by further laminating the cover film 3 on the film adhesive 1.
  • the adhesive sheets 100 and 110 may be formed by using a film-shaped adhesive agent prepared in advance.
  • the adhesive sheet 100 can be formed by laminating under a predetermined condition (for example, room temperature (20° C.) or a heated state) using a roll laminator, a vacuum laminator, or the like. Since the adhesive sheet 100 can be continuously manufactured and is excellent in efficiency, it may be formed using a roll laminator in a heated state.
  • the adhesive sheet is a dicing/die bonding integrated adhesive sheet in which the base material 2 is a dicing tape.
  • the process of laminating on the semiconductor wafer is performed once, so that the work efficiency can be improved.
  • the dicing tape examples include plastic films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film and polyimide film.
  • the dicing tape may be subjected to surface treatment such as primer coating, UV treatment, corona discharge treatment, polishing treatment, and etching treatment, if necessary.
  • the dicing tape may have adhesiveness.
  • Such a dicing tape may be one in which the above-mentioned plastic film is provided with tackiness, or one in which the above-mentioned plastic film is provided with an adhesive layer.
  • the pressure-sensitive adhesive layer may be either a pressure-sensitive type or a radiation-curable type, has a sufficient adhesive force so that the semiconductor element does not scatter during dicing, and does not damage the semiconductor element in the subsequent semiconductor element pickup step.
  • a pressure-sensitive type or a radiation-curable type
  • has a sufficient adhesive force so that the semiconductor element does not scatter during dicing, and does not damage the semiconductor element in the subsequent semiconductor element pickup step.
  • the thickness of the dicing tape may be 60 to 150 ⁇ m or 70 to 130 ⁇ m from the viewpoints of economy and handleability of the film.
  • FIG. 4 is a schematic cross-sectional view showing another embodiment of the adhesive sheet.
  • FIG. 5 is a schematic cross-sectional view showing another embodiment of the adhesive sheet.
  • the adhesive sheet 120 shown in FIG. 4 includes the dicing tape 7, the adhesive layer 6, and the film adhesive 1 in this order.
  • the adhesive sheet 130 shown in FIG. 5 includes the dicing tape 7 and the film adhesive 1 provided on the dicing tape 7.
  • the adhesive sheet 120 can be obtained, for example, by providing the pressure-sensitive adhesive layer 6 on the dicing tape 7 and further laminating the film adhesive 1 on the pressure-sensitive adhesive layer 6.
  • the adhesive sheet 130 can be obtained, for example, by bonding the dicing tape 7 and the film adhesive 1 together.
  • the film-like adhesive and the adhesive sheet may be used for manufacturing a semiconductor device, and the film-like adhesive and the dicing tape may be applied to a semiconductor wafer or a semiconductor element (semiconductor chip) that has already been cut into small pieces at 0° C. After bonding at 90° C., a semiconductor element with a film adhesive is obtained by cutting with a rotary blade, a laser or stretching, and then the semiconductor element with the film adhesive is applied to an organic substrate, a lead frame, or another semiconductor element. It may be used in the manufacture of a semiconductor device including a step of adhering on.
  • semiconductor wafers include single crystal silicon, polycrystalline silicon, various ceramics, and compound semiconductors such as gallium arsenide.
  • the film adhesive and the adhesive sheet include semiconductor elements such as IC and LSI, lead frames such as 42 alloy lead frame and copper lead frame; plastic films such as polyimide resin and epoxy resin; It can be used as a die-bonding adhesive for bonding a plastic impregnated and cured with an epoxy resin or the like; a semiconductor mounting support member such as ceramics such as alumina or the like.
  • the film adhesive and the adhesive sheet are also suitably used as an adhesive for adhering semiconductor elements to each other in a Stacked-PKG having a structure in which a plurality of semiconductor elements are stacked.
  • one semiconductor element serves as a support member on which the semiconductor element is mounted.
  • the film adhesive and the adhesive sheet are, for example, a protective sheet for protecting the back surface of the semiconductor element of the flip-chip type semiconductor device, and a material for sealing between the surface of the semiconductor element of the flip-chip type semiconductor device and the adherend. It can also be used as a sealing sheet or the like.
  • a semiconductor device manufactured using a film adhesive will be specifically described with reference to the drawings. Note that semiconductor devices having various structures have been proposed in recent years, and the application of the film adhesive according to the present embodiment is not limited to the semiconductor device having the structure described below.
  • FIG. 6 is a schematic sectional view showing an embodiment of a semiconductor device.
  • the semiconductor device 200 shown in FIG. 6 is provided between the semiconductor element 9, the supporting member 10 on which the semiconductor element 9 is mounted, the semiconductor element 9 and the supporting member 10, and is an adhesive for bonding the semiconductor element 9 and the supporting member 10. And a member (cured product 1c of film adhesive).
  • a connection terminal (not shown) of the semiconductor element 9 is electrically connected to an external connection terminal (not shown) via a wire 11 and sealed by a sealing material 12.
  • FIG. 7 is a schematic cross-sectional view showing another embodiment of the semiconductor device.
  • the first-stage semiconductor element 9a is bonded to the support member 10 on which the terminals 13 are formed by an adhesive member (cured material 1c of film adhesive), and the first-stage semiconductor element 9a.
  • the semiconductor element 9b of the second stage is further adhered to the top by an adhesive member (cured product 1c of film adhesive).
  • the connection terminals (not shown) of the semiconductor element 9 a in the first stage and the semiconductor element 9 b in the second stage are electrically connected to the external connection terminals via the wires 11 and sealed by the sealing material 12.
  • the film adhesive according to the present embodiment can be suitably used for a semiconductor device having a structure in which a plurality of semiconductor elements are stacked.
  • the semiconductor device (semiconductor package) shown in FIGS. 6 and 7 has, for example, a film adhesive interposed between the semiconductor element and the support member or between the semiconductor element and the two by heat-pressing them. Are bonded, and then, if necessary, a wire bonding step, a sealing step with a sealing material, a heating and melting step including reflow with solder, and the like.
  • the heating temperature in the thermocompression bonding step is usually 20 to 250° C.
  • the load is usually 0.1 to 200 N
  • the heating time is usually 0.1 to 300 seconds.
  • the supporting member or It may be a method of attaching to a semiconductor element.
  • the support member may include a member made of copper.
  • a member made of copper is used as a constituent member of the semiconductor device.
  • the member made of copper for example, a lead frame, a wiring, a wire, a heat dissipating material, etc. can be mentioned, but even if copper is used for any member, the influence of copper ions can be reduced. Is.
  • the method of manufacturing a semiconductor device using the dicing/die-bonding integrated adhesive sheet is not limited to the method of manufacturing a semiconductor device described below.
  • a semiconductor wafer is pressure-bonded to the film-like adhesive 1 on the adhesive sheet 120 (adhesive sheet with integrated dicing and die bonding), and this is adhesively held and fixed (mounting step).
  • This step may be performed while pressing with a pressing means such as a pressure roll.
  • the semiconductor wafer is diced.
  • the semiconductor wafer is cut into a predetermined size, and a plurality of individual semiconductor elements (semiconductor chips) with a film-like adhesive are manufactured.
  • the dicing can be performed, for example, from the circuit surface side of the semiconductor wafer according to a conventional method.
  • a cutting method called full-cut in which a dicing tape is cut a method in which a semiconductor wafer is cut into half and cut by cooling and pulling, a laser cutting method, and the like can be employed.
  • the dicing device used in this step is not particularly limited, and a conventionally known device can be used.
  • the pickup method is not particularly limited, and various conventionally known methods can be adopted. For example, there is a method in which individual semiconductor elements are pushed up by a needle from the side of an adhesive sheet integrated with dicing and die bonding, and the pushed up semiconductor elements are picked up by a pickup device.
  • the pressure-sensitive adhesive layer is radiation (for example, ultraviolet ray) curable, pick up is performed after the pressure-sensitive adhesive layer is irradiated with radiation. As a result, the adhesive strength of the pressure-sensitive adhesive layer to the film adhesive is reduced, and the semiconductor element can be easily peeled off. As a result, the pickup can be performed without damaging the semiconductor element.
  • radiation for example, ultraviolet ray
  • the semiconductor element with a film adhesive formed by dicing is adhered to the support member for mounting the semiconductor element via the film adhesive.
  • Bonding may be done by crimping.
  • the conditions for die bonding are not particularly limited, and can be set appropriately as needed. Specifically, for example, the die bond temperature may be 80 to 160° C., the bonding load may be 5 to 15 N, and the bonding time may be 1 to 10 seconds.
  • thermosetting the film adhesive may be provided.
  • thermosetting the film-like adhesive that bonds the support member and the semiconductor element in the bonding step it is possible to more firmly bond and fix.
  • pressure may be applied simultaneously to cure.
  • the heating temperature in this step can be appropriately changed depending on the constituents of the film adhesive.
  • the heating temperature may be, for example, 60 to 200°C.
  • the temperature or pressure may be changed stepwise.
  • a wire bonding process is performed to electrically connect the tip of the terminal portion (inner lead) of the support member and the electrode pad on the semiconductor element with a bonding wire.
  • a bonding wire for example, a gold wire, an aluminum wire, a copper wire or the like is used.
  • the temperature for wire bonding may be in the range of 80 to 250°C or 80 to 220°C.
  • the heating time may be several seconds to several minutes.
  • the connection may be performed by using the vibration energy of ultrasonic waves and the compression energy of applied pressure together while being heated within the above temperature range.
  • a sealing process is performed to seal the semiconductor element with the sealing resin.
  • This step is performed to protect the semiconductor element or the bonding wire mounted on the support member.
  • This step is performed by molding the resin for sealing with a mold.
  • the sealing resin may be, for example, an epoxy resin. The substrate and the residue are embedded by heat and pressure at the time of sealing, and peeling due to bubbles at the adhesive interface can be prevented.
  • the sealing resin that is insufficiently cured in the sealing process is completely cured. Even if the film adhesive is not cured by heat in the sealing step, the film adhesive can be cured by heat as well as the curing of the sealing resin in this step, so that the adhesive fixation can be achieved.
  • the heating temperature in this step can be appropriately set depending on the type of the sealing resin, and may be, for example, in the range of 165 to 185° C., and the heating time may be about 0.5 to 8 hours.
  • the semiconductor element with the film adhesive adhered to the support member is heated using a reflow oven.
  • a resin-sealed semiconductor device may be surface-mounted on the support member.
  • the surface mounting method include reflow soldering in which solder is supplied in advance on a printed wiring board and then heated and melted by hot air or the like to perform soldering.
  • the heating method include hot air reflow and infrared reflow.
  • the heating method may be a method of heating the whole or a method of heating a local portion.
  • the heating temperature may be, for example, in the range of 240 to 280°C.
  • the film adhesive according to the present embodiment tends to have lower cohesive force and improved embedding property by using a specific acrylic rubber. Therefore, it is difficult for air bubbles to be caught in the semiconductor device, the air bubbles can be easily diffused in the sealing step, and peeling due to the air bubbles at the adhesive interface can be prevented.
  • A Specific epoxy resin (A1) YDCN-700-10 (trade name, Nippon Steel & Sumikin Chemical Co., Ltd., o-cresol novolac type epoxy resin, epoxy equivalent: 209 g/eq)
  • A3) EXA-830CRP (trade name, manufactured by DIC Corporation, BPF type epoxy resin, epoxy equivalent: 155 to 163 g/eq)
  • Epoxy resin other than the specific epoxy resin epoxy resin having an epoxy equivalent outside the range of 140 to 220 g/eq
  • A1 NC-3000 trade name, manufactured by Nippon Kayaku Co., Ltd., biphenylaralkyl-type epoxy resin, epoxy equivalent: 265 to 285 g/eq
  • A2 NC-2000-L trade name, manufactured by Nippon Kayaku Co., Ltd., phenylaralkyl type epoxy resin, epoxy equivalent: 229 to 244 g/eq
  • Phenolic resin other than the specific phenolic resin phenolic resin having a hydroxyl equivalent outside the range of 90 to 130 g/eq
  • B1 HE-100C-30 trade name, manufactured by Air Water Co., phenylaralkyl-type phenol resin, hydroxyl group equivalent: 174 g/eq
  • B2 MEH-7851H trade name, manufactured by Meiwa Kasei Co., Ltd., biphenylaralkyl-type phenol resin, hydroxyl equivalent: 216 g/eq
  • KH-CT-865 trade name, manufactured by Hitachi Chemical Co., Ltd., acrylic rubber containing no constitutional unit derived from acrylonitrile, weight average molecular weight: 480,000, Tg: 7° C.
  • P CN / P CO of (C3) since it does not contain a constituent unit derived from acrylonitrile, (C2) equal to or a value of P CN / P CO of less (i.e., P CN / P CO It is estimated that ⁇ 0.001).
  • the highest absorbance peak was a peak point between the two points between 1670 cm -1 and 1860 cm -1. 1670cm and -1 and a linear baseline between the two points between 1860 cm -1, and a baseline point that it is the same wave number and the peak point on the base line, the difference in absorbance of the baseline point and the peak point.
  • the height (P CO ) of the absorption peak derived from the stretching vibration of the carbonyl group was used.
  • D Inorganic filler (D1) R972 (trade name, manufactured by Nippon Aerosil Co., Ltd., silica, average particle size: 0.016 ⁇ m)
  • D2 Silica filler dispersion liquid (average particle size: 0.050 ⁇ m) in which the silica filler in YA050C (trade name, manufactured by Admatechs Co., Ltd., silica filler dispersion liquid) is surface-treated with a vinylsilane coupling agent and an alkylsilane coupling agent. )
  • D3 SC2050-HLG trade name, manufactured by Admatechs Co., Ltd., silica filler dispersion, average particle size 0.50 ⁇ m
  • E Coupling agent (E1) A-189 (trade name, manufactured by Nippon Unicar Co., Ltd., ⁇ -mercaptopropyltrimethoxysilane) (E2) A-1160 (trade name, ⁇ -ureidopropyltriethoxysilane manufactured by Nippon Unicar Co., Ltd.)
  • the produced adhesive varnish was filtered with a 100-mesh filter and vacuum degassed.
  • a polyethylene terephthalate (PET) film having a thickness of 38 ⁇ m and subjected to a release treatment was prepared, and the adhesive varnish after vacuum defoaming was applied on the PET film.
  • the applied adhesive varnish is heated and dried in two stages of 90° C. for 5 minutes and 130° C. for 5 minutes to obtain the film adhesives of Examples 1 to 4 and Comparative Examples 1 to 9 in the B stage state. Obtained.
  • the film adhesive was adjusted to have a thickness of 10 ⁇ m depending on the coating amount of the adhesive varnish.
  • NMP N-methyl-2-pyrrolidone
  • the film adhesives of Examples 1 to 4 and Comparative Examples 1 to 9 in the B stage state were further dried by heating at 170° C. for 1 hour, and the film adhesives of Examples 1 to 4 and Comparative Examples 1 to 9 in the C stage state.
  • a film adhesive was prepared.
  • the film-like adhesives (thickness: 10 ⁇ m) of Examples 1 to 4 and Comparative Examples 1 to 9 in the C stage state were cut out into circles each having a diameter of about 3 cm.
  • two silicon packing sheets having a thickness of 1.5 mm, an outer diameter of about 3 cm and an inner diameter of 1.8 cm were prepared.
  • the film adhesive cut out in a circular shape was sandwiched between two silicon packing sheets, sandwiched between the flange portions of two glass cells having a volume of 50 mL, and fixed with a rubber band.
  • a voltage was applied at an applied voltage of 24.0 V at room temperature, and measurement of the current value was started after the voltage was applied. The measurement is performed until the current value exceeds 5 ⁇ A, and the time when the current value becomes 1 ⁇ A is the copper ion permeation time.
  • the copper ion permeation time is 200 minutes or more, “A”, and the copper ion permeation time is 140 minutes. If it is less than 200 minutes, it is designated as "B”, if the copper ion permeation time is 80 minutes or more and less than 140 minutes, it is designated as "C”, and if the copper ion permeation time is less than 80 minutes, it is designated as "D”. did.
  • the obtained dicing sample was cut using Full Auto Dicer DFD-6361 (manufactured by Disco Corporation).
  • the cutting was performed by a step cut method using two blades, and a dicing blade ZH05-SD3500-N1-xx-DD and ZH05-SD4000-N1-xx-BB (both manufactured by Disco Corporation) were used.
  • the cutting conditions were a blade rotation speed of 4000 rpm, a cutting speed of 50 mm/sec, and a chip size of 7.5 mm ⁇ 7.5 mm.
  • the cutting was performed in the first step so that the semiconductor wafer remained about 30 ⁇ m, and then in the second step so that a cut of about 20 ⁇ m was formed in the dicing tape.
  • the resin-sealed semiconductor device was analyzed by an ultrasonic imaging device (SAT) (manufactured by Hitachi Construction Machinery Co., Ltd., HYE-FOCUS), and the limit time (0 hours, 1 hour, 2 hours) in which no void was generated. , Or 3 hours) was evaluated as embedding property. "A” when the limit time was 3 hours, "B” when the limit time was 2 hours, "C” when the limit time was 1 hour, and 0 hours. The case was designated as "D”. The results are shown in Table 1, Table 2 and Table 3. In this evaluation, it can be said that the longer the limit time in which voids do not occur, the better the embeddability because the embedding is possible even if a thermal history is given.
  • SAT ultrasonic imaging device
  • the die shear strength after curing was measured using the semiconductor element (semiconductor chip) with the film adhesive.
  • the semiconductor chip was thermocompression bonded onto a solder resist (Taiyo Holdings Co., Ltd., trade name: AUS-308).
  • the pressure bonding conditions were a temperature of 120° C., a time of 1 second, and a pressure of 0.1 MPa. Then, the sample obtained by pressure bonding was put into a dryer and cured at 170° C. for 1 hour.
  • the film-like adhesives of Examples 1 to 4 were all B or more in terms of copper ion permeation time, embeddability, and adhesiveness. It was superior to the film adhesives of Examples 1 to 9.
  • the film-like adhesive of the present invention was able to sufficiently suppress the defects caused by the movement of copper ions in the adhesive, and further was excellent in the adhesiveness to the substrate and the embedding property.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Adhesive Tapes (AREA)
  • Adhesives Or Adhesive Processes (AREA)
  • Dicing (AREA)

Abstract

L'invention concerne un adhésif sous forme de film pour lier un élément semi-conducteur et un élément de support pour monter l'élément semi-conducteur. Cet adhésif sous forme de film contient une résine époxy ayant une quantité équivalente d'époxy de 140-220 g/éq, une résine phénolique ayant une quantité équivalente de groupe hydroxyle de 90-130 g/éq. et une résine thermoplastique. La teneur de la résine thermoplastique est de 55 à 75 % en masse sur la base de la quantité totale de l'adhésif sous forme de film.
PCT/JP2019/049478 2018-12-19 2019-12-17 Adhésif sous forme de film, feuille adhésive, et dispositif à semi-conducteur et son procédé de fabrication WO2020129996A1 (fr)

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JP2018-237451 2018-12-19
JP2018237451A JP2022033064A (ja) 2018-12-19 2018-12-19 フィルム状接着剤、接着シート、並びに半導体装置及びその製造方法

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009030043A (ja) * 2007-06-28 2009-02-12 Lintec Corp 粘接着剤組成物、粘接着シートおよび半導体装置の製造方法
JP2009161588A (ja) * 2007-12-28 2009-07-23 Lintec Corp 粘接着剤組成物、粘接着シートおよび半導体装置の製造方法
JP2010132807A (ja) * 2008-12-05 2010-06-17 Lintec Corp 接着剤組成物、接着シートおよび半導体装置の製造方法
WO2015016352A1 (fr) * 2013-08-02 2015-02-05 リンテック株式会社 Composition adhésive, feuille adhésive, et procédé de production d'un dispositif semi-conducteur

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009030043A (ja) * 2007-06-28 2009-02-12 Lintec Corp 粘接着剤組成物、粘接着シートおよび半導体装置の製造方法
JP2009161588A (ja) * 2007-12-28 2009-07-23 Lintec Corp 粘接着剤組成物、粘接着シートおよび半導体装置の製造方法
JP2010132807A (ja) * 2008-12-05 2010-06-17 Lintec Corp 接着剤組成物、接着シートおよび半導体装置の製造方法
WO2015016352A1 (fr) * 2013-08-02 2015-02-05 リンテック株式会社 Composition adhésive, feuille adhésive, et procédé de production d'un dispositif semi-conducteur

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JP2022033064A (ja) 2022-02-28

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