JPWO2013157567A1 - Adhesive composition, adhesive sheet, and method for manufacturing semiconductor device - Google Patents

Abstract

Adhesive composition that can be used in the manufacture of multi-stage packages, exhibits excellent chip-to-chip bond strength after curing, and can achieve high package reliability, particularly in semiconductor devices, and single-layer adhesion comprising the adhesive composition Provided are a film, an adhesive sheet having an adhesive layer made of the adhesive composition, and a method for producing a semiconductor device using the adhesive sheet. The adhesive composition according to the present invention includes an acrylic polymer (A) having a functional group capable of reacting with an isocyanate group, an epoxy resin (B), a thermosetting agent (C), and a coupling agent (D) having an isocyanate group. including.

Description

  The present invention relates to an adhesive composition particularly suitable for use in a process of dicing a silicon wafer or the like, and bonding (die bonding) the obtained semiconductor chip to an organic substrate, a lead frame or another semiconductor chip. The present invention relates to an adhesive sheet having an adhesive layer made of an adhesive composition and a method for manufacturing a semiconductor device using the adhesive sheet.

  A semiconductor wafer made of silicon, gallium arsenide or the like is manufactured in a large diameter state, and this wafer is cut and separated (diced) into element pieces (semiconductor chips) and then transferred to the next mounting step. At this time, the semiconductor wafer is subjected to dicing, cleaning, drying, expanding, and pick-up processes in a state where the semiconductor wafer is previously adhered to the adhesive sheet, and then transferred to the next bonding process.

  In order to simplify the processes of the pick-up process and the bonding process among these processes, various dicing / die-bonding adhesive sheets having both a wafer fixing function and a die bonding function have been proposed (Patent Document 1, etc.) ). The adhesive sheet disclosed in Patent Document 1 enables so-called direct die bonding, and the application process of the die bonding adhesive can be omitted. This adhesive contains an acrylic polymer, an unsaturated hydrocarbon group-containing epoxy resin, and a thermosetting agent, and optionally contains a coupling agent such as a silane coupling agent.

  The required physical properties of semiconductor devices in recent years have become very strict. For example, in the connection of electronic components, a surface mounting method (reflow) is performed in which the entire package is exposed to a high temperature equal to or higher than the solder melting point. Furthermore, in recent years, the mounting temperature has increased to about 260 ° C. due to the shift to lead-free solder. For this reason, the stress generated inside the semiconductor package at the time of mounting becomes larger than before, and there is a high possibility of causing problems such as peeling at the adhesive interface and package cracks. Therefore, in the above-mentioned Patent Document 1, as an epoxy resin, an unsaturated hydrocarbon group-containing epoxy resin is used, and the compatibility of the acrylic polymer with the epoxy resin is improved, thereby improving the adhesion reliability. .

  For high-density mounting, a package structure in which chips are stacked in multiple stages has been proposed. In this package structure, not only the connection between the substrate and the chip but also the adhesion between the chip and the chip is required. In a multistage package, a chip is stacked on the chip via an adhesive layer, and after the adhesive layer is cured, wire bonding is performed, and further, chip stacking, curing of the adhesive layer, and Y-bonding are sequentially performed, and the chip is mounted. Laminate. However, in this method, the adhesive layer is cured each time the chips are stacked. Therefore, when the number of stacked chips increases, the number of manufacturing steps increases and improvement in production efficiency is required.

  Therefore, without hardening the adhesive layer when stacking chips, stacking and wire bonding are performed with the adhesive layer uncured or semi-cured, and after stacking all the chips, the mold sealing process is performed. It has been studied to fully cure the adhesive layer in a lump by using exposure to high temperature for a long time. However, when this manufacturing method is employed, the adhesive layer is in an uncured or semi-cured state during wire bonding. Since a high temperature of 150 ° C. or higher is required during wire bonding, the adhesive layer may be partially cured. In this undesired curing, no pressure is applied, so when the adhesive layer is cured, the adhesive force is simply lost, leading to a decrease in adhesive strength. In view of such circumstances, an adhesive layer that has excellent adhesion between chips and can improve reliability is desired.

JP 2008-133330 A

  Therefore, the present invention provides an adhesive composition that can be used in the manufacture of multistage packages, exhibits excellent chip-to-chip adhesive strength after curing, and can achieve high package reliability, particularly in a semiconductor device, and the adhesive composition It is an object of the present invention to provide a single-layer adhesive film made of a product, an adhesive sheet having an adhesive layer made of the adhesive composition, and a method for manufacturing a semiconductor device using the adhesive sheet.

The present invention for solving the above problems includes the following gist.
[1] An adhesive composition comprising an acrylic polymer (A) having a functional group capable of reacting with an isocyanate group, an epoxy resin (B), a thermosetting agent (C), and a coupling agent (D) having an isocyanate group.

[2] The adhesive composition according to [1], wherein the functional group is a hydroxyl group.

[3] A single-layer adhesive film comprising the adhesive composition according to [1] or [2].

[4] An adhesive sheet in which an adhesive layer made of the adhesive composition according to [1] or [2] is formed on a support so as to be peelable.

[5] The adhesive sheet according to [4], wherein the support is a resin film.

[6] The adhesive sheet according to [4], wherein the support is a pressure-sensitive adhesive sheet including a pressure-sensitive adhesive layer.

[7] A semiconductor wafer is attached to the adhesive layer of the adhesive sheet according to any one of [4] to [6], and the semiconductor wafer and the adhesive layer are diced to form a semiconductor chip, and the semiconductor chip is bonded to the semiconductor chip. A method of manufacturing a semiconductor device, comprising a step of leaving an adhesive layer to remain and peeling from a support, and bonding the semiconductor chip onto a die pad portion or another semiconductor chip via the adhesive layer.

  According to the present invention, chips or a chip and a substrate are bonded to each other, and particularly, the adhesiveness between chips is excellent. For this reason, even in the case of adopting the process of collectively curing the adhesive layer when manufacturing a multistage package, it is possible to bond a semiconductor chip to another semiconductor chip or a substrate with excellent adhesive strength, under a severe environment. In this case, a semiconductor device having high package reliability can be obtained.

  Hereinafter, the adhesive composition of the present invention, the adhesive sheet, and a method for producing a semiconductor device using the sheet will be described more specifically.

(Adhesive composition)
The adhesive composition according to the present invention is an acrylic polymer (A) having a functional group capable of reacting with an isocyanate group (hereinafter also referred to as “component (A)”. The same applies to other components), an epoxy resin. (B), a thermosetting agent (C), and a coupling agent (D) having an isocyanate group are included as essential components, and other components may be included as necessary in order to improve various physical properties. Hereinafter, each of these components will be described in detail.

(A) Acrylic polymer The acrylic polymer (A) has a functional group capable of reacting with an isocyanate group (hereinafter sometimes referred to as “reactive functional group”). Since the acrylic polymer (A) has a reactive functional group, the acrylic polymer (A) is bonded to an isocyanate group of a coupling agent (D) described later via the reactive functional group. Moreover, since the coupling agent (D) has a functional group capable of reacting with an inorganic substance in addition to an isocyanate group, an adherend (semiconductor wafer, semiconductor chip) adhered to an adhesive layer made of the adhesive composition. And substrate). For this reason, the acrylic polymer (A) is bonded to the adherend via the coupling agent (D), and the adherends are firmly bonded to each other. As a result, the reliability of the semiconductor device can be improved. Moreover, when an organic polyvalent isocyanate compound is used as a crosslinking agent described later, the reactive functional group also reacts with the organic polyvalent isocyanate compound to form a crosslinked structure.

  Examples of the reactive functional group include a hydroxyl group, a carboxyl group, and an amino group, and a hydroxyl group is preferable. The acrylic polymer having a hydroxyl group has good compatibility with the epoxy resin (B) described later.

As a monomer constituting the acrylic polymer (A), a monomer having a reactive functional group is used. Examples of the monomer having a hydroxyl group include a (meth) acrylic acid ester having a hydroxyl group.
Examples of the (meth) acrylic acid ester having a hydroxyl group include hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate.
Examples of the monomer having a hydroxyl group other than the (meth) acrylic acid ester having a hydroxyl group include vinyl alcohol and N-methylolacrylamide. Examples of the monomer having a carboxyl group include (meth) acrylic acid, maleic acid, and fumaric acid.

  The acrylic polymer (A) has at least an alkyl group such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate as another monomer constituting the acrylic polymer (A). (Meth) acrylic acid alkyl ester; (meth) acrylic acid cycloalkyl ester, (meth) acrylic acid benzyl ester, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclo 1 type or more of (meth) acrylic acid ester which does not have reactive functional groups, such as (meth) acrylic acid ester which has cyclic skeletons, such as pentenyl oxyethyl (meth) acrylate and imide (meth) acrylate, is included. These may be used alone or in combination of two or more.

  In the acrylic polymer (A), the structural unit derived from the monomer having a reactive functional group is preferably contained in the range of 1 to 50% by mass, and contained in the range of 2 to 25% by mass. More preferred. When the adhesive composition of the present invention contains an organic polyvalent isocyanate compound as a crosslinking agent, the structural unit derived from the monomer having a reactive functional group in the acrylic polymer (A) is in the above range. By doing so, the reactive functional group and the functional group (isocyanate group) of the crosslinking agent (G) react to form a three-dimensional network structure, and the crosslinking density of the acrylic polymer (A) can be increased. As a result, an adhesive composition having excellent shear strength can be obtained. Further, since the water absorption of the adhesive composition is reduced, a semiconductor device having excellent package reliability can be obtained.

  In the acrylic polymer (A), the structural unit derived from the (meth) acrylic acid ester having no reactive functional group is usually contained in the range of 50 to 99% by mass, and contained in the range of 70 to 90% by mass. It is preferable that

  In addition to the monomer having the reactive functional group and the (meth) acrylic acid ester not having the reactive functional group, vinyl acetate, acrylonitrile, styrene, etc. You may use as a monomer which comprises a coalescence (A).

  The weight average molecular weight (Mw) of the acrylic polymer (A) is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. If the weight average molecular weight of the acrylic polymer (A) is too low, the adhesive force between the adhesive layer and the support becomes high, and chip pick-up failure may occur. If the weight average molecular weight of the acrylic polymer (A) is too high, the adhesive layer may not be able to follow the unevenness of the adherend, which may cause generation of voids and the like. The weight average molecular weight of the acrylic polymer (A) is a polystyrene equivalent value measured by a gel permeation chromatography (GPC) method.

  The glass transition temperature (Tg) of the acrylic polymer (A) is preferably -60 to 70 ° C, more preferably -30 to 50 ° C, and further preferably 0 to 30 ° C. If the Tg of the acrylic polymer (A) is too low, the peeling force between the adhesive layer and the support may be increased, resulting in chip pickup failure. If the Tg of the acrylic polymer (A) is too high, the adhesive force for fixing the wafer may be insufficient.

  The acrylic polymer (A) is preferably contained in a proportion of 50% by mass or more in the total mass of the adhesive composition. By adopting such a configuration, it becomes a preferable property when used in a process of collectively curing the adhesive layer. This is because when such a process is employed, the adhesive layer is in an uncured or semi-cured state during wire bonding. For this reason, the chips vibrate and displace during wire bonding, and particularly when the chips are stacked together, the adhesion between the chips may decrease, and as a result, the reliability of the semiconductor device may decrease. When the acrylic polymer (A) is contained in the adhesive composition in the above ratio, the adhesive layer has appropriate elasticity and vibration and displacement tend to be suppressed. Thus, when content of an acrylic polymer (A) is increased in order to ensure process suitability, the amount of curable components (epoxy resin (B) and thermosetting agent (C)) is relatively reduced. . For this reason, curing may be insufficient, but the adhesive composition of the present invention solves such a problem of insufficient curing because the acrylic polymer (A) and the coupling agent (D) are bonded. it can. In addition, an increase in the abundance of the acrylic polymer (A) in the adhesive composition also means an increase in the abundance of reactive functional groups in the adhesive composition. Therefore, the density of the bond between the acrylic polymer (A) and the coupling agent (D) can be increased. The acrylic polymer (A) is more preferably contained in a proportion of 60 to 90% by mass and more preferably 65 to 80% by mass in the total mass of the adhesive composition. .

  A reactive double bond group may be added to the acrylic polymer (A). In the acrylic polymer having a reactive double bond group, the reactive double bond group is bonded by ultraviolet irradiation to form a crosslinked structure. The reactive double bond group is preferably a reactive vinyl group, allyl group or (meth) acryloyl group, and the reactive double bond group can be introduced into the acrylic polymer (A) by a conventional method. By having such a reactive double bond group in the acrylic polymer (A), for example, the adhesive sheet of the present invention is used as a dicing die bonding sheet, and after being attached to a wafer, an energy ray such as ultraviolet rays is applied before the dicing process. By irradiation, the acrylic polymer (A) having a reactive double bond group can be reacted and pre-cured. By pre-curing, the adhesive layer is relatively soft before curing, so it has good adhesion to the wafer, and has an appropriate hardness during dicing, and adhesion of the adhesive to the dicing blade and other problems Can be prevented. Further, it becomes possible to control the peelability at the interface between the support (resin film or dicing tape) and the adhesive layer. Furthermore, since the hardness is higher in the precured state than in the uncured state, stability during wire bonding is improved. In addition, the effect obtained by such preliminary curing is obtained when an epoxy resin having a reactive double bond group, a thermosetting agent having a reactive double bond group, or an energy beam polymerizable compound (I) described later is blended. Can be obtained as well.

(B) Epoxy Resin As the epoxy resin (B), conventionally known various epoxy resins can be used. Epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, triphenolmethane. Type epoxy resin, heterocyclic type epoxy resin, stilbene type epoxy resin, fused ring aromatic hydrocarbon modified epoxy resin, and epoxy resins containing two or more functional groups in the structural unit It is done. These epoxy resins may be used alone or in combination of two or more.

  The epoxy resin (B) is used in an amount of 3 to 50% by mass, more preferably 5 to 40% by mass, and particularly preferably 5 to 35% by mass in 100% by mass of the adhesive composition. When the proportion of the epoxy resin (B) is less than 3% by mass, an adhesive layer having sufficient adhesive strength may not be obtained. On the other hand, if the proportion of the epoxy resin (B) exceeds 50% by mass, the film forming property is lost, and the adhesive layer cannot be formed into a sheet shape, which may make it difficult to produce a dicing die bonding sheet.

  As described above, by making the ratio of the acrylic polymer (A) in the total mass of the adhesive composition a predetermined value or more, the effect of improving the wire bonding suitability of the adhesive layer, the acrylic polymer (A) and the cup An effect of increasing the density of the bond of the ring agent (D) may be obtained. The design guideline of the adhesive composition for obtaining such an effect is blended in the adhesive composition of the acrylic polymer (A) and the epoxy resin (B) which are usually employed as the main components of the adhesive composition. From the viewpoint of mass ratio, the ratio (A: B) is preferably 50:50 to 95: 5, more preferably 65:35 to 90:10, and 70:30 to Particularly preferred is 85:15.

  The epoxy resin (B) may have the following skeleton.

In the formula, Xs may be the same or different and are represented by —O— (ether), —COO— (ester), —OCO— (ester), —OCH (CH ₃ ) O— (acetal). A divalent group selected, preferably —O— or —OCH (CH ₃ ) O—.

R is a divalent group selected from alkylene, polyether skeleton, polybutadiene skeleton, polyisoprene skeleton, which may be the same or different, and each of alkylene and polyether skeleton has a side chain. It may also be a structure containing a cycloalkane skeleton. The divalent radical R is, preferably, for example, _{- (CH 2 CH 2) -} (OCH 2 CH 2) m - _{or, - (CH (CH 3)} CH 2) - (OCH (CH 3) CH 2) m -An alkylene or ether skeleton having the structural formula (m is 0 to 5), specifically, alkylene of ethylene or propylene, ethyleneoxyethyl group, di (ethyleneoxy) ethyl group, tri (ethyleneoxy) Polyether skeletons such as ethyl group, propyleneoxypropyl group, di (propyleneoxy) propyl group, and tri (propyleneoxy) propyl group are listed.

  In the adhesive composition of the present invention, it is preferable to use an epoxy resin having a reactive double bond group as the epoxy resin (B). Since the epoxy resin (B) has a reactive double bond group, the acrylic polymer (A) and a coupling agent (D) described later are compared with an epoxy resin having no reactive double bond group. High compatibility with. Further, when such an epoxy resin is used, the reliability tends to be improved as compared with an adhesive composition containing only an epoxy resin having no reactive double bond group.

  Examples of the reactive double bond group include the same ones that can be added to the acrylic polymer (A) described above. Further, the epoxy resin having a reactive double bond group can be polymerized and cured by irradiation with energy rays such as ultraviolet rays and electron beams in the same manner as the acrylic polymer having a reactive double bond group.

(C) Thermosetting agent The thermosetting agent (C) functions as a curing agent for the epoxy resin (B). Examples of the thermosetting agent (C) include compounds having two or more functional groups capable of reacting with an epoxy group in the molecule, such as phenolic hydroxyl groups, alcoholic hydroxyl groups, amino groups, carboxyl groups, acids. An anhydride group etc. are mentioned. In these, a phenolic hydroxyl group, an amino group, and an acid anhydride group are preferable, and a phenolic hydroxyl group and an amino group are more preferable. An adhesive layer containing a thermosetting agent having an amino group (amine-based thermosetting agent) has higher hygroscopicity than an adhesive layer containing a thermosetting agent having a phenolic hydroxyl group (phenolic thermosetting agent). Therefore, the adhesive layer has a large decrease in adhesiveness after the introduction of wet heat conditions, but the adhesive layer containing a phenolic thermosetting agent has high moist heat resistance. Is small. Therefore, as the thermosetting agent (C), a compound having two or more phenolic hydroxyl groups capable of reacting with an epoxy group in the molecule is particularly preferable.

  Specific examples of the thermosetting agent (C) include phenolic thermosetting agents such as polyfunctional phenolic resins, biphenols, novolac type phenolic resins, dicyclopentadiene type phenolic resins, triphenolmethane type phenolic resins, and aralkylphenolic resins; An amine thermosetting agent such as DICY (dicyandiamide) can be used. A thermosetting agent (C) may be used individually by 1 type, and may use 2 or more types together.

  A thermosetting agent having a reactive double bond group may be used as the thermosetting agent (C). As the thermosetting agent having a reactive double bond group, for example, a compound obtained by substituting a part of the hydroxyl group of the phenol resin with a group containing a reactive double bond group or an aromatic ring of the phenol resin is reactive. Examples thereof include compounds in which a group containing a double bond group is directly bonded. Examples of the reactive double bond group include the same ones that can be added to the acrylic polymer (A) described above. The thermosetting agent (C) having a reactive double bond group can be polymerized and cured by irradiation with energy rays such as ultraviolet rays and electron beams in the same manner as the acrylic polymer having a reactive double bond group. it can.

  In the adhesive composition of the present invention, the content of the thermosetting agent (C) is usually 0.1 to 500 parts by mass, preferably 1 to 200 parts by mass with respect to 100 parts by mass of the epoxy resin (B). is there. When content of a thermosetting agent (C) is less than the said range, the sclerosis | hardenability of adhesive composition may be insufficient and the adhesive bond layer which has sufficient adhesive force may not be obtained. When the content of the thermosetting agent (C) exceeds the above range, the moisture absorption rate of the adhesive composition may increase, and the reliability of the semiconductor package may decrease.

(D) Coupling agent The coupling agent (D) has an isocyanate group. Examples of the coupling agent having an isocyanate group include 3-isocyanatopropyltriethoxysilane, isocyanatemethylmethyldibutoxysilane, and isocyanatemethyltriethoxysilane. Examples of these commercially available products include 3-isocyanatopropyltriethoxysilane (KBE-9007 manufactured by Shin-Etsu Chemical Co., Ltd.). Since the adhesive composition contains the coupling agent (D), the isocyanate group is bonded to the reactive functional group of the acrylic polymer (A), while the functional group capable of bonding to an inorganic substance such as an alkoxy group is formed. In order to bond to the adherend surface, the effect of the present invention that improves the adhesiveness between the adhesive layer composition and the adherend is exhibited, and the package reliability can be improved.

  The coupling agent is preferably 0.001 to 10 parts by mass, more preferably 0.005 to 100 parts by mass in total of the acrylic polymer (A), the epoxy resin (B) and the thermosetting agent (C). It is contained in an amount of 10 parts by mass, particularly preferably 0.01 to 5 parts by mass. Moreover, it is preferably 0.1 to 2 parts by mass, more preferably 0.3 to 1.5 parts by mass, and further preferably 0.4 to 1.3 parts by mass with respect to 100 parts by mass of the acrylic polymer (A). Included in range. If the amount of the coupling agent is too large, the coupling agent volatilizes when the adhesive composition is heated, which may cause voids. On the other hand, if the amount of the coupling agent is too small, the effect of adding the coupling agent may not be sufficiently exhibited. By setting the amount of the coupling agent (D) within the above range, the effect of the present invention that improves the adhesiveness between the adhesive layer composition and the adherend is more exhibited, and the package reliability can be further improved. it can.

The other component adhesive composition may contain the following components in addition to the above components.

(E) It is preferable that a photoinitiator adhesive composition contains a photoinitiator. The adhesive composition is an acrylic polymer having a reactive double bond group as the acrylic polymer (A), an epoxy resin having a reactive double bond group as the epoxy resin (B), and a thermosetting agent (C). As a thermosetting agent having a reactive double bond group, or an energy beam polymerizable compound (I) described later (hereinafter also referred to as “acrylic polymer having a reactive double bond group (A)”). .)), By containing a photopolymerization initiator, polymerization of these components by energy beam irradiation is more efficiently performed.

  Specific examples of the photopolymerization initiator (E) include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, benzoin dimethyl ketal, 2, 4-diethylthioxanthone, α-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 1,2-diphenylmethane, 2-hydroxy-2-methyl -1- [4- (1-Methylvinyl) phenyl] propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and β-chloran Examples include suraquinone. A photoinitiator (E) can be used individually by 1 type or in combination of 2 or more types.

  When the photopolymerization initiator (E) is used, the blending ratio thereof includes the acrylic polymer having the reactive double bond group, the epoxy resin having the reactive double bond group, and the heat having the reactive double bond group. What is necessary is just to set suitably based on the quantity of the reactive double bond group which a hardening | curing agent and energy-beam polymeric compound (I) have. Although not limited at all, for example, an acrylic polymer having a reactive double bond group, an epoxy resin having a reactive double bond group, a thermosetting agent having a reactive double bond group, and energy beam polymerization The amount is usually 0.1 to 10 parts by mass, preferably 1 to 5 parts by mass with respect to 100 parts by mass of the total amount of the functional compound (I). If the content of the photopolymerization initiator (E) is lower than the above range, a satisfactory reaction may not be obtained due to insufficient photopolymerization, and if it exceeds the above range, a residue that does not contribute to photopolymerization is generated, and the adhesive. The curability of the composition may be insufficient.

(F) Curing accelerator The curing accelerator (F) is used to adjust the curing rate of the adhesive composition. Preferred curing accelerators include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl- Imidazoles such as 4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole; Organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine; And tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphinetetraphenylborate. These can be used individually by 1 type or in mixture of 2 or more types.

  When using a hardening accelerator (F), a hardening accelerator (F) becomes like this. Preferably it is 0.01-10 mass parts with respect to 100 mass parts of epoxy resins (B), More preferably, it is 0.1-1 mass part. Included in the amount of. By containing the curing accelerator (F) in an amount within the above range, it has excellent adhesive properties even when exposed to high temperatures and high humidity, and high package reliability even when exposed to severe reflow conditions. Sex can be achieved. If the content of the curing accelerator (F) is small, sufficient adhesive properties cannot be obtained due to insufficient curing, and if it is excessive, the curing accelerator having high polarity will pass through the adhesive layer under high temperature and high humidity. The reliability of the package is lowered by segregation and segregation.

(G) A crosslinking agent (G) can be added to the crosslinking agent adhesive composition in order to adjust the initial adhesive force and cohesive strength of the adhesive layer. In addition, when mix | blending a crosslinking agent, the functional group which reacts with a crosslinking agent is contained in the said acrylic polymer (A).
Examples of the crosslinking agent (G) include organic polyvalent isocyanate compounds and organic polyvalent imine compounds.
When the crosslinking agent (G) is an organic polyvalent isocyanate compound, the reactive functional group of the acrylic polymer (A) also serves as a functional group that reacts with the crosslinking agent.

  Examples of the organic polyvalent isocyanate compound include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, alicyclic polyvalent isocyanate compounds, trimers of these organic polyvalent isocyanate compounds, and these organic polyvalent isocyanate compounds. And a terminal isocyanate urethane prepolymer obtained by reacting a polyol compound with a polyol compound.

  Examples of organic polyvalent isocyanate compounds include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane-4,4′-diisocyanate, diphenylmethane. -2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, and their polyhydric alcohol adducts, As well as lysine isocyanate.

  Since the acrylic polymer (A) in the present invention has a functional group capable of reacting with an isocyanate group, it is preferable to use an isocyanate-based crosslinking agent. Thereby, reaction with a crosslinking agent and an acrylic polymer (A) occurs, and a crosslinked structure can be simply introduced into the adhesive.

  Examples of the organic polyvalent imine compound include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri -Β-aziridinylpropionate and N, N′-toluene-2,4-bis (1-aziridinecarboxyamide) triethylenemelamine can be exemplified.

  When the acrylic polymer (A) has a carboxyl group as a reactive functional group, it reacts with the carboxyl group by using an organic imine compound as a crosslinking agent. That is, the carboxyl group also functions as a functional group that reacts with the crosslinking agent. Thereby, a crosslinked structure can be introduced into the adhesive.

  When using a crosslinking agent (G), a crosslinking agent (G) is 0.01-20 mass parts normally with respect to 100 mass parts of acrylic polymers (A), Preferably it is 0.1-10 mass parts, More preferably, it is 0. Used at a ratio of 5 to 5 parts by mass.

(H) The filler adhesive composition may contain a filler in order to adjust the hardness of the adhesive layer after curing. The filler may be either a so-called inorganic filler or an organic filler, but an inorganic filler is preferably used from the viewpoint of heat resistance.

  Examples of the material for the filler include silica, alumina, calcium carbonate, calcium silicate, magnesium hydroxide, aluminum hydroxide, titanium oxide, carbon black, talc, mica, and clay. Of these, silica is preferable.

  The average particle diameter of the filler is preferably in the range of 0.005 to 2 μm. When the average particle diameter of the filler is in the above range, the adhesiveness can be exhibited without impairing the sticking property with the semiconductor wafer. The “average particle diameter” indicates a volume average diameter measured by a laser diffraction / scattering method.

  It is preferable that the said filler is contained in 5-100 mass parts with respect to a total of 100 mass parts of an acrylic polymer (A), an epoxy resin (B), and a thermosetting agent (C). If the amount of the filler is too large, adhesion to the wafer and adhesion to the substrate may be deteriorated. If the amount of the filler particles is too small, the effect of filler addition may not be sufficiently exhibited.

  When the adhesive layer contains the filler (H) in such a range, the adhesive layer can easily obtain an elastic modulus enough to withstand vibration during wire bonding even in an uncured or semi-cured state. For this reason, it is suppressed that a chip | tip vibrates and displaces at the time of wire bonding, and there exists a tendency which can implement wire bonding stably.

  In addition, since the adhesive composition of the present invention contains the coupling agent (D), the functional group capable of binding to the inorganic substance of the coupling agent (D) binds to the surface of the filler (D), thereby The coalescence (A) and the filler may be combined. In this case, the cohesiveness of the adhesive layer after curing is improved.

(I) The energy beam polymerizable compound may be blended in the energy beam polymerizable compound adhesive composition. The energy beam polymerizable compound (I) contains a reactive double bond group, and is polymerized and cured when irradiated with energy rays such as ultraviolet rays and electron beams. Specific examples of the energy ray polymerizable compound (I) include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, and 1,4. Examples include acrylate compounds such as butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, epoxy-modified acrylate, polyether acrylate, and itaconic acid oligomer. Such a compound has at least one polymerizable double bond in the molecule, and usually has a weight average molecular weight of about 100 to 30,000, preferably about 300 to 10,000. When using energy-beam polymeric compound (I), the compounding quantity is although it does not specifically limit, It is preferable to use in the ratio of about 1-50 mass% in the solid content total mass of adhesive composition.

(J) A thermoplastic resin (J) may be used for the thermoplastic resin adhesive composition. A thermoplastic resin (J) is mix | blended in order to hold | maintain the flexibility of the adhesive bond layer after hardening. The thermoplastic resin (J) preferably has a weight average molecular weight of 1,000 to 100,000, and more preferably 3,000 to 80,000. By containing the thermoplastic resin (J), the delamination between the support and the adhesive layer in the pick-up process of the semiconductor chip can be easily performed, and the adhesive layer follows the unevenness of the substrate and voids, etc. Occurrence can be suppressed.

  The glass transition temperature of the thermoplastic resin (J) is preferably -30 to 150 ° C, more preferably -20 to 120 ° C. If the glass transition temperature of the thermoplastic resin (J) is too low, the peeling force between the adhesive layer and the support may be increased, resulting in chip pick-up failure. If it is too high, the adhesive force for fixing the wafer will be increased. May be insufficient.

  Examples of the thermoplastic resin (J) include polyester resin, urethane resin, phenoxy resin, polybutene, polybutadiene, and polystyrene. These can be used individually by 1 type or in mixture of 2 or more types.

  When using a thermoplastic resin (J), the compounding quantity is preferably 1 to 300 parts by mass with respect to a total of 100 parts by mass of the acrylic polymer (A), epoxy resin (B) and thermosetting agent (C). More preferably, it is in the range of 2 to 100 parts by mass. When the content of the thermoplastic resin (J) is within this range, the above effect can be obtained.

(K) Other coupling agent Moreover, you may mix | blend the coupling agent which does not have an isocyanate group with the adhesive composition other than the said coupling agent (D). Examples of such a coupling agent (K) include silane coupling agents having no isocyanate group. Specifically, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane , Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- (methacrylopropyl) trimethoxysilane, γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropyltrimethoxy Silane, N-6- (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ- Mercaptopropylmethyldimethoxysilane, bis (3-to (Riethoxysilylpropyl) tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolesilane and the like. These can be used individually by 1 type or in mixture of 2 or more types. When the coupling agent (K) is used, the other coupling agent (K) is preferably 0 with respect to 100 parts by mass in total of the acrylic polymer (A), the epoxy resin (B) and the thermosetting agent (C). 0.001 to 10 parts by mass, more preferably 0.005 to 10 parts by mass, and particularly preferably 0.01 to 5 parts by mass.

(L) In addition to the above, various additives may be added to the general-purpose additive adhesive composition as necessary. Various additives include plasticizers, antistatic agents, antioxidants, pigments, dyes, gettering agents and the like.

  The adhesive layer made of the adhesive composition comprising the above components has pressure-sensitive adhesiveness and heat-curing property. In an uncured state, the adhesive layer is lightly pressed or heated to various adherends at room temperature. Can be softened and pasted. Moreover, an acrylic polymer (A) and a coupling agent (D) couple | bond together, and a coupling agent (D) couple | bonds with a chip | tip and a board | substrate. For this reason, even when the process of batch-curing the adhesive layer is adopted in the manufacture of multi-stage packages, the semiconductor chip can be bonded to other semiconductor chips and substrates with excellent adhesive strength, and high package reliability Can be obtained. When the adhesive layer contains an acrylic polymer (A) having a reactive double bond group, it also has energy ray curability and can be precured by irradiation with energy rays before the main curing. . Pre-curing increases the hardness of the adhesive layer and improves the stability during wire bonding.

  The adhesive composition may be a single-layer adhesive film formed by forming the adhesive composition, but preferably an adhesive layer in which the adhesive layer made of the above-mentioned adhesive composition is formed on the support so as to be peelable. It is a sheet.

(Adhesive sheet)
Hereinafter, taking an adhesive sheet in which an adhesive layer is formed so as to be peelable on a support as an example, preferred embodiments and usage embodiments thereof will be described. When using an adhesive sheet in which the adhesive layer is formed so as to be peelable on the support, the adhesive layer is adhered to an adherend such as a wafer or chip, the support is peeled off, and the adhesive layer is attached. Transfer to the body. The shape of the adhesive sheet according to the present invention can be any shape such as a tape shape or a label shape. The support may be a resin film having no tack on the surface, or may be a so-called dicing sheet (adhesive sheet having an adhesive layer).

  Examples of the resin film used as the support for the adhesive sheet include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate. Phthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate copolymer film, ionomer resin film, ethylene / (meth) acrylic acid copolymer film, ethylene / (meth) acrylic acid ester copolymer film, polystyrene film Films such as polycarbonate film, polyimide film, and fluororesin film are used. These crosslinked films are also used. Furthermore, these laminated films may be sufficient. Moreover, the film etc. which colored these can be used. In the case where the adhesive layer has energy ray curability, those having energy ray permeability are preferable. Moreover, when it is necessary to visually recognize the surface of the adhered adherend while the adhesive sheet is being adhered, it is preferable that it has visible light transparency (transparent or translucent).

  The adhesive sheet according to the present invention is affixed to various adherends, and after subjecting the adherend to necessary processing, the adhesive layer is peeled off from the support in a state where the adhesive layer remains fixed to the adherend. That is, it is used for a process including a step of transferring an adhesive layer from a support to an adherend. For this reason, the surface tension of the surface in contact with the adhesive layer of the support (resin film) is preferably 40 mN / m or less, more preferably 37 mN / m or less, and particularly preferably 35 mN / m or less. The lower limit is usually about 25 mN / m. Such a resin film having a low surface tension can be obtained by appropriately selecting the material, and can also be obtained by applying a release agent to the surface of the resin film and performing a release treatment.

  As the release agent used for the release treatment of the resin film, alkyd, silicone, fluorine, unsaturated polyester, polyolefin, wax, etc. are used, and in particular, alkyd, silicone, and fluorine release agents. Is preferable because it has heat resistance.

  In order to release the surface of the resin film using the release agent described above, the release agent can be applied as it is without solvent, or diluted or emulsified with a solvent, using a gravure coater, Mayer bar coater, air knife coater, roll coater, etc. Then, the laminate may be formed by room temperature or heating or electron beam curing, wet lamination, dry lamination, hot melt lamination, melt extrusion lamination, coextrusion processing, or the like.

  The support may be a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer. The pressure-sensitive adhesive sheet has a pressure-sensitive adhesive layer on the resin film as described above, and the adhesive layer is detachably laminated on the pressure-sensitive adhesive layer. Therefore, the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet can be composed of a known pressure-sensitive adhesive having removability, and by selecting a pressure-sensitive adhesive such as an ultraviolet curable type, a heat-foaming type, a water swelling type, or a weakly viscous type. The adhesive layer can be easily peeled off.

  Further, the adhesive sheet may have a shape in which the support and the adhesive layer are previously punched in the same shape as the adherend (semiconductor wafer or the like). In particular, the laminate composed of the support and the adhesive layer is preferably in a form held on a long support.

  The thickness of the support is usually 10 to 500 μm, preferably 15 to 300 μm, particularly preferably about 20 to 250 μm. When the support is an adhesive sheet, the layer made of the adhesive usually occupies a thickness of about 1 to 50 μm in the thickness of the support. Moreover, the thickness of an adhesive bond layer is 2-500 micrometers normally, Preferably it is 6-300 micrometers, Most preferably, it is about 10-150 micrometers.

  In order to protect the adhesive layer, the adhesive of the adhesive sheet, the adhesive layer for fixing to the jig described below, etc., a release film is laminated on the upper surface of the adhesive layer before use. It may be left. As the release film, one in which a release agent such as a silicone resin is applied to a plastic material such as a polyethylene terephthalate film or a polypropylene film is used. In addition, an adhesive layer or an adhesive tape may be separately provided on the outer peripheral portion of the surface of the adhesive sheet in order to fix other jigs such as a ring frame.

  The production method of the adhesive sheet is not particularly limited. When the support is a resin film, the adhesive composition may be applied and dried on the resin film to form an adhesive layer. Good. Moreover, you may manufacture by providing an adhesive bond layer on a peeling film and transferring this to the said resin film or a dicing sheet. In any stage of the manufacturing process, the adhesive layer may be cut by punching or the like so as to have the same shape as the shape of the wafer to be attached or a concentric shape larger than the wafer.

  Next, a method of using the adhesive sheet according to the present invention will be described taking as an example the case where the adhesive sheet is applied to the manufacture of a semiconductor device.

(Method for manufacturing semiconductor device)
In the method for manufacturing a semiconductor device according to the present invention, a semiconductor wafer is attached to the adhesive layer of the adhesive sheet, the semiconductor wafer and the adhesive layer are diced into semiconductor chips, and the adhesive layer is formed on the back surface of the semiconductor chip. A step of allowing the semiconductor chip to adhere and remain on the die pad portion of the organic substrate or the lead frame or another semiconductor chip via an adhesive layer.

Hereinafter, a method for manufacturing a semiconductor device according to the present invention will be described in detail.
In the method for manufacturing a semiconductor device according to the present invention, first, a semiconductor wafer having a circuit formed on the front surface and a ground back surface is prepared.

  The semiconductor wafer may be a silicon wafer or a compound semiconductor wafer such as gallium / arsenic. Formation of a circuit on the wafer surface can be performed by various methods including conventionally used methods such as an etching method and a lift-off method. Next, the opposite surface (back surface) of the circuit surface of the semiconductor wafer is ground. The grinding method is not particularly limited, and grinding may be performed by a known means using a grinder or the like. At the time of back surface grinding, an adhesive sheet called a surface protection sheet is attached to the circuit surface in order to protect the circuit on the surface. In the back surface grinding, the circuit surface side (that is, the surface protection sheet side) of the wafer is fixed by a chuck table or the like, and the back surface side on which no circuit is formed is ground by a grinder. The thickness of the wafer after grinding is not particularly limited, but is usually about 20 to 500 μm.

  Next, the back side of the ring frame and the semiconductor wafer is placed on the adhesive layer of the adhesive sheet according to the present invention, lightly pressed, and heat is applied in some cases to fix the semiconductor wafer while softening the adhesive layer. When an acrylic polymer (A) having a reactive double bond group is blended in the adhesive layer, the adhesive layer is irradiated with energy rays from the support side to react with the reactive double bond group. The adhesive layer may be pre-cured to reduce the adhesive force between the adhesive layer and the support. Examples of the energy rays to be irradiated include ultraviolet rays (UV) and electron beams (EB), and preferably ultraviolet rays are used. Next, the semiconductor wafer and the adhesive layer are cut using a cutting means such as a dicing saw to obtain a semiconductor chip. The cutting depth at this time is a depth that takes into account the sum of the thickness of the semiconductor wafer and the adhesive layer and the wear of the dicing saw, and the adhesive layer is also cut to the same size as the chip. The energy beam irradiation may be performed at any stage after the semiconductor wafer is pasted and before the semiconductor chip is peeled off (pickup). For example, the irradiation may be performed after dicing or after the following expanding step. Good. Further, the energy beam irradiation may be performed in a plurality of times.

  Then, if necessary, when the adhesive sheet is expanded, the interval between the semiconductor chips is expanded, and the semiconductor chips can be picked up more easily. At this time, a deviation occurs between the adhesive layer and the support, the adhesive force between the adhesive layer and the support is reduced, and the pick-up property of the semiconductor chip is improved. When the semiconductor chip is picked up in this manner, the cut adhesive layer can be adhered to the back surface of the semiconductor chip and peeled off from the support.

  Next, the semiconductor chip is placed on the die pad of the lead frame which is the chip mounting portion or on the surface of another semiconductor chip (lower chip) through the adhesive layer. In order to improve the adhesiveness of the adhesive layer, the chip mounting portion may be heated before or immediately after mounting the semiconductor chip. The heating temperature is usually 80 to 200 ° C, preferably 100 to 180 ° C, and the heating time is usually 0.1 seconds to 5 minutes, preferably 0.5 seconds to 3 minutes. Moreover, the pressure of pressurization at the time of mounting is usually 1 kPa to 200 MPa.

  After the semiconductor chip is placed on the chip mounting portion, the adhesive layer is removed by heating before resin sealing without waiting for the main curing of the adhesive layer using heating in resin sealing as described later. It may be cured. The heating conditions at this time are in the above heating temperature range, and the heating time is usually 1 to 180 minutes, preferably 10 to 120 minutes.

  Alternatively, the adhesive layer may be set to a temporarily bonded state without performing the heat treatment after placement, and the adhesive layer may be fully cured after the wire bonding by using heating in resin sealing normally performed in package manufacturing. Through such a process, the adhesive layer is cured, and the semiconductor chip and the chip mounting portion can be firmly bonded. When the adhesive layer is cured by irradiating the above-mentioned energy rays before wire bonding, the cohesiveness of the adhesive layer is improved, and thus wire bonding tends to be performed stably. Furthermore, since the adhesive layer is softened under the die bonding condition, it is sufficiently embedded in the unevenness of the chip mounting portion, and generation of voids can be prevented and the reliability of the package is improved. When such a process is adopted, the reaction of components that contribute to the thermosetting of the adhesive layer partly proceeds due to heating in wire bonding, and there is a concern that the package reliability of the semiconductor device may be reduced. However, by using the adhesive composition of the present invention, the adhesiveness of the adhesive layer to the chip tends to be improved, and the package reliability tends to be maintained.

  The adhesive composition and adhesive sheet of the present invention can be used for bonding semiconductor compounds, glass, ceramics, metals, etc., in addition to the above-described methods of use.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. In the following examples and comparative examples, <Evaluation of Embedding to Substrate> and <Evaluation of IR Reflow Resistance> were performed as follows.

<Evaluation of embedding on a substrate>
After removing the release film from the adhesive sheets obtained in Examples and Comparative Examples, the adhesive layer was attached to a glass chip (8 mm × 8 mm thickness 150 μm), and then the support was removed to obtain a glass chip with an adhesive layer. .
A circuit pattern is formed on a copper foil of a foil-clad laminate (CCL-HL830 manufactured by Mitsubishi Gas Chemical Co., Inc., copper foil thickness: 18 μm), and a solder resist (PSR-4000 AUS303 made by Taiyo Ink) is provided on the pattern. The glass chip with the adhesive layer was pressure-bonded onto the substrate (LN001E-001 PCB (Au) AUS303, manufactured by Chino Giken Co., Ltd.) through the adhesive layer under the conditions of 150 ° C. and 100 gf for 1 second. Next, thermocompression bonding was performed at a pressure of 6.9 MPa, 175 ° C. for 2 minutes per chip using a heat seal tester (TP-701, manufactured by Tester Sangyo Co., Ltd.) assuming a molding process. Thereafter, the interface between the adhesive layer and the substrate was observed from the glass chip surface side at a magnification of 20 using a digital microscope (VHX-200 manufactured by Keyence Corporation) to confirm the embedding property. The embeddability was determined to be good if 95% or more of the chip area was embedded excluding the portion including an air layer such as a void.

<IR reflow resistance evaluation>
(Manufacture of semiconductor chips)
The adhesive sheets of Examples and Comparative Examples were attached to the polished surface of a dry-polished silicon wafer (150 mm diameter, 75 μm thick) with a tape mounter (Adwill RAD2500 manufactured by Lintec Corporation), and fixed to a ring frame for wafer dicing. Then, ultraviolet rays were irradiated (220 mW / cm ² , 160 mJ / cm ² ) from the support surface using an ultraviolet irradiation device (Adwill RAD2000 manufactured by Lintec Corporation). Next, the wafer was diced into a chip size of 8 mm × 8 mm using a dicing apparatus (DFD651 manufactured by DISCO Corporation). The amount of cut during dicing was such that the support was cut by 20 μm.

(Manufacture of semiconductor packages)
As a substrate, a circuit pattern is formed on a copper foil-clad laminate (CCL-HL830, manufactured by Mitsubishi Gas Chemical Co., Ltd., copper foil thickness: 18 μm), and a solder resist (PSR-4000 AUS303, manufactured by Taiyo Ink) is formed on the pattern. (LN001E-001 PCB (Au) AUS303, manufactured by Chino Giken Co., Ltd.) was used. The chip on the adhesive sheet obtained above was picked up from the support together with the adhesive layer, and pressed onto the substrate under the conditions of 120 ° C., 250 gf, and 0.5 seconds via the adhesive layer. Thereafter, another semiconductor chip was again pressure-bonded on the bonded semiconductor chip through an adhesive layer under the conditions of 120 ° C., 250 gf, and 0.5 seconds, thereby stacking two semiconductor chips. Twenty-seven laminated chips on this substrate were produced, and then sealed with a mold resin (KE-1100AS3, manufactured by Kyocera Chemical Co., Ltd.) so as to have a sealing thickness of 400 μm (sealing device: APC Yamada Co., Ltd. MPC-06M TriAl Press) The resin was cured at 175 ° C. for 5 hours.
Next, the sealed substrate is affixed to a dicing tape (Adwill D-510T manufactured by Lintec Corporation), and is subjected to reliability evaluation by dicing into a size of 8 mm × 8 mm using a dicing apparatus (DFD651 manufactured by Disco Corporation). The semiconductor package was obtained.

(Evaluation of semiconductor package surface mountability)
The obtained semiconductor package is left to stand for 60 hours at 60 ° C. and 60% relative humidity to absorb moisture, and then subjected to IR reflow (reflow oven: Sagami Riko Co., Ltd.) with preheating at 160 ° C. and a maximum temperature of 260 ° C. Manufactured WL-15-20DNX type) three times. After that, the presence or absence of floating / peeling of the joints and the occurrence of package cracks were detected using a scanning ultrasonic flaw detector (Hy-Focus manufactured by Hitachi Construction Machinery Finetech Co., Ltd.) and a cross-section polishing machine (Refinetech Polisher HV manufactured by RefineTech Co., Ltd.). ) Were cut out and evaluated by cross-sectional observation using a digital microscope (VHX-1000 manufactured by Keyence Corporation).
When peeling of 0.5 mm or more in length is observed at the substrate / semiconductor chip joint or the semiconductor chip / semiconductor chip joint, it is judged that the peeling has occurred, and 27 packages are put into the test and no peeling occurs. I counted the number.

<Adhesive composition>
Each component which comprises an adhesive composition is shown below.
(A) Acrylic polymer: copolymer consisting of 85 parts by mass of methyl acrylate and 15 parts by mass of 2-hydroxyethyl acrylate (Mw: 350,000, Tg: 6 ° C.)
(B) Epoxy resin: acryloyl group-added cresol novolac type epoxy resin (CNA-147 manufactured by Nippon Kayaku Co., Ltd.)
(C) Thermosetting agent: zylock type phenolic resin (Mirex XLC-4L manufactured by Mitsui Chemicals, Inc.)
(D) Coupling agent:
(D-1) Silane coupling agent having an isocyanate group (Shin-Etsu Chemical Co., Ltd. KBE-9007, alkoxy group equivalent 68.3 g / eq, molecular weight 205)
(D-2) Silane coupling agent having an epoxy group (KBE-402 manufactured by Shin-Etsu Chemical Co., Ltd., alkoxy group equivalent 124.2 g / eq, molecular weight 248)
(D-3) Silane coupling agent having an epoxy group (Shin-Etsu Chemical Co., Ltd. KBE-403, alkoxy group equivalent 92.8 g / eq, molecular weight 278)
(D-4) Silane coupling agent having a mercapto group (Shin-Etsu Chemical Co., Ltd. KBM-803, alkoxy group equivalent 65.4 g / eq, molecular weight 196)
In addition, the usage-amount of the coupling agent was adjusted so that the number-of-moles of the alkoxy group derived from the coupling agent contained in an adhesive composition might become substantially equal in Example 1 and Comparative Examples 1-3.
(E) Photopolymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.)
(F) Curing accelerator: Imidazole (Curesol 2PHZ manufactured by Shikoku Kasei Kogyo Co., Ltd.)
(G) Crosslinking agent: aromatic polyisocyanate (Nihon Polyurethane Industry Co., Ltd. Coronate L)

(Examples and Comparative Examples)
The above components were blended in the amounts (mass ratio) shown in Table 1 using methyl ethyl ketone as a solvent to obtain a methyl ethyl ketone solution (solid concentration 30 mass%) of the adhesive composition. The adhesive composition solution was applied onto the release-treated surface of a release film (SP-PET 381031 manufactured by Lintec Co., Ltd.) that had been subjected to a release treatment with silicone, and dried (drying condition: 100 ° C. in an oven) to a thickness of 20 μm. After bonding for 1 minute, it was bonded to a support (polyethylene film, thickness 100 μm, surface tension 33 mN / m), and the adhesive layer was transferred onto the support to obtain an adhesive sheet. Table 1 shows the evaluation results of embedding property and IR reflow resistance of the obtained adhesive sheet.

From the above results, it can be seen that by adopting the configuration of the present invention, both the chips and the chip and the substrate have high adhesion and can maintain reliability. For this reason, by providing the adhesive composition, single-layer adhesive film and adhesive sheet of the present invention, it becomes easy to produce a multi-stack semiconductor package, and productivity is improved.

Claims (7)

  An adhesive composition comprising an acrylic polymer (A) having a functional group capable of reacting with an isocyanate group, an epoxy resin (B), a thermosetting agent (C), and a coupling agent (D) having an isocyanate group.   The adhesive composition according to claim 1, wherein the functional group is a hydroxyl group.   A single-layer adhesive film comprising the adhesive composition according to claim 1 or 2.   An adhesive sheet in which an adhesive layer made of the adhesive composition according to claim 1 or 2 is detachably formed on a support.   The adhesive sheet according to claim 4, wherein the support is a resin film.   The adhesive sheet according to claim 4, wherein the support is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer.   A semiconductor wafer is affixed to the adhesive layer of the adhesive sheet according to claim 4, the semiconductor wafer and the adhesive layer are diced into semiconductor chips, and the adhesive layer is fixedly left on the semiconductor chips. A method of manufacturing a semiconductor device including a step of peeling from a support and bonding the semiconductor chip onto a die pad portion or another semiconductor chip via the adhesive layer.