JP2012025879A - Adhesive composition and adhesive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive composition, improved in softening temperature, for bonding a wafer.SOLUTION: The adhesive composition for bonding the wafer comprises: a resin having adhesiveness; and a filler. Moreover, an adhesive film includes an adhesive layer containing the adhesive composition.

Description

  The present invention relates to an adhesive composition and an adhesive film for bonding wafers.

  As an adhesive composition, Patent Document 1 describes an adhesive containing a hydrocarbon resin. Patent Document 2 describes an adhesive resin composition containing silica fine powder having an organic group chemically reacting with an adhesive resin component on its surface, and Patent Document 3 describes a filler as a main ingredient. The adhesive added to is described.

JP 2010-109324 A (published on May 13, 2010) Japanese Patent Laid-Open No. 10-287854 (released on October 27, 1998) JP-A-8-319466 (published on December 3, 1996)

  However, after bonding the wafer and the glass substrate using the above-described conventional adhesive, for example, when a high temperature process is performed near 250 ° C., the adhesive melts from the end surface of the wafer, so-called delamination. (Adhesive may melt from the edge of the wafer). Therefore, it is required to further improve (higher) the softening temperature of the adhesive composition.

  The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide an adhesive composition and an adhesive film that have a higher (higher) softening temperature for bonding wafers. There is to do.

  In order to solve the above problems, an adhesive composition according to the present invention is an adhesive composition for adhering a wafer, and includes a resin having adhesiveness and a filler. .

  In the adhesive composition according to the present invention, the filler content relative to the resin is preferably 20% by weight or more and 70% by weight or less.

  In the adhesive composition according to the present invention, the average particle size of the filler is preferably 0.5 μm or more and 5 μm or less.

  In the adhesive composition according to the present invention, the filler is preferably an inorganic filler.

  Moreover, in the adhesive composition which concerns on this invention, it is preferable that the heat resistance of the said filler is 300 degreeC or more.

  In the adhesive composition according to the present invention, the resin is preferably a hydrocarbon resin.

  In the adhesive composition according to the present invention, the hydrocarbon resin is preferably selected from the group consisting of a cycloolefin polymer, a terpene resin, a rosin resin, and a petroleum resin.

  In order to solve the above-described problems, the adhesive film according to the present invention includes an adhesive layer containing any one of the above-described adhesive compositions on the film.

  The adhesive composition according to the present invention is an adhesive composition for adhering a wafer as described above, and includes a resin having adhesiveness and a filler. Therefore, it is possible to provide an adhesive composition and an adhesive film having a higher (higher) softening temperature.

It is a graph which shows the measurement result using TMA (thermomechanical analyzer) about the adhesive composition in Example 3 of this invention. It is a graph which shows the measurement result using TMA about the adhesive composition in Example 4 of this invention. It is a graph which shows the measurement result using TMA about the adhesive composition in Example 7 of this invention. It is a graph which shows the measurement result using TMA about the adhesive composition in Example 8 of this invention. It is a graph which shows the measurement result using TMA about the adhesive composition in Example 9 of this invention. It is a graph which shows the measurement result using TMA about the adhesive composition in Example 10 of this invention. It is a graph which shows the measurement result using TMA about the adhesive composition in the comparative example of this invention. It is a graph which shows the relationship between stress and filler content at the time of using the adhesive composition in each Example of this invention.

  An embodiment of the present invention will be described in detail below.

[Adhesive composition]
The adhesive composition according to the present embodiment is an adhesive composition for adhering a wafer, and includes a resin having adhesiveness and a filler.

  Since the adhesive composition of the present embodiment includes a filler, dissolution at a high temperature is physically suppressed, so that the softening temperature is further improved (increased). Therefore, if the wafer is bonded to a glass substrate or the like using this adhesive composition, the adhesive melts from the end face of the wafer during a subsequent high-temperature process (such as a vapor deposition process such as PVD or CVD) ( Delamination) can be suppressed. Therefore, the adhesive composition according to the present embodiment can be suitably used for wafer bonding.

  Hereinafter, each component included in the adhesive composition will be described.

<Filler>
Although it does not specifically limit as a filler, For example, it is preferable that it is an inorganic filler. Inorganic fillers include silica, alumina, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, basic magnesium carbonate, Calcium carbonate, zinc carbonate, barium carbonate, dosonite, hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, talc, clay, mica, montmorillonite, bentonite, sepiolite, imogolite, cerissato, glass fiber, glass beads, silica balun , Aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon balun, zinc borate, and various magnetic powders.

  The inorganic filler may be surface-treated with various coupling agents such as silane and titanate. As a surface treatment method, a dry method, a slurry method or a spray method, a method of directly treating an inorganic filler with various coupling agents, an integral blend method such as a direct method or a masterbatch method, or a dry concentrate method, etc. The method is mentioned.

  Examples of commercially available products that can be used as fillers include silicone resin powder, silicone composite powder, and silicone rubber powder manufactured by Shin-Etsu Chemical Co., Ltd.

  The filler content relative to the resin is preferably 20% by weight or more and 70% by weight or less. If the filler content is 20% by weight or more, the softening temperature of the adhesive is sufficiently high, so that delamination can be suppressed. Moreover, if it is 70 weight% or less, sufficient adhesive force can be hold | maintained. Here, the “content ratio of the filler relative to the resin” refers to the content ratio when the resin is defined as 100% by weight.

  In addition, the content rate of a filler should just be the quantity which can avoid peeling of the wafer adhere | attached with the adhesive composition, and the higher one is preferable from a viewpoint of the raise of the softening temperature of an adhesive agent, and relaxation of stress. Therefore, the filler content is more preferably 50 wt% or more and 70 wt% or less.

  The average particle size of the filler is preferably 0.5 μm or more and 5 μm or less. Thereby, since it disperse | distributes without settling in an adhesive composition, the function can fully be exhibited. The average particle diameter of the filler is preferably 0.5 μm or more and 1 μm or less from the viewpoint of relaxing the stress of the wafer. If an adhesive composition containing such a filler having an average particle diameter is used, the amount of warpage of the wafer when the wafer is subjected to a high temperature process after being bonded to a glass substrate or the like can be reduced. Therefore, subsequent process flow is possible.

  Moreover, it is preferable that the heat resistance of a filler is 300 degreeC or more. Thereby, delamination can be suppressed effectively. In the present specification, “having heat resistance of 300 ° C. or higher” means that the rate of change in weight when heated from room temperature to 300 ° C. is 1% or less.

<Resin>
Any resin may be used as long as it has adhesiveness, and examples thereof include hydrocarbon resins, acrylic-styrene resins, and maleimide resins.

(Hydrocarbon resin)
As the hydrocarbon resin, a cycloolefin polymer (hereinafter sometimes referred to as “resin (A)”), and at least one resin selected from the group consisting of a terpene resin, a rosin resin and a petroleum resin (hereinafter referred to as “the resin (A)”). Resin (B) ”), and the like, but is not limited thereto.

  The resin (A) may be a resin obtained by polymerizing a monomer component containing a cycloolefin monomer. Specific examples include a ring-opening (co) polymer of a monomer component containing a cycloolefin monomer, and a resin obtained by addition (co) polymerization of a monomer component containing a cycloolefin monomer.

  Examples of the cycloolefin monomer contained in the monomer component constituting the resin (A) include bicyclic compounds such as norbornene and norbornadiene, tricyclic compounds such as dicyclopentadiene and dihydroxypentadiene, and tetracyclododecene. Tetracycles, pentacycles such as cyclopentadiene trimer, heptacycles such as tetracyclopentadiene, or alkyl (methyl, ethyl, propyl, butyl, etc.) substituted polyalkenyls, alkenyl (vinyl, etc.) Examples include substituted, alkylidene (such as ethylidene) substituted, aryl (such as phenyl, tolyl, naphthyl) substituted, and the like. Among these, norbornene-based monomers selected from the group consisting of norbornene, tetracyclododecene, and alkyl-substituted products thereof are preferable.

  The monomer component constituting the resin (A) may contain another monomer copolymerizable with the above-described cycloolefin-based monomer, and preferably contains, for example, an alkene monomer. Examples of the alkene monomer include ethylene, propylene, 1-butene, isobutene, 1-hexene, and α-olefin. The alkene monomer may be linear or branched.

  As for the monomer component which comprises resin (A), it is preferable that 50 mass% or more is the said cycloolefin type monomer, More preferably, 60 mass% or more is the said cycloolefin type monomer. When the cycloolefin-based monomer is 50% by mass or more of the whole monomer component, the adhesive strength in a high temperature environment is good.

  The resin (A) is a resin having no polar group, such as a resin obtained by polymerizing a monomer component composed of a cycloolefin monomer and an alkene monomer, at high temperatures. It is preferable for suppressing generation of gas.

  The polymerization method and polymerization conditions for polymerizing the monomer components are not particularly limited and may be appropriately set according to a conventional method.

  Examples of commercially available products that can be used as the resin (A) include “TOPAS” manufactured by Polyplastics, “APEL” manufactured by Mitsui Chemicals, “ZEONOR” and “ZEONEX” manufactured by Nippon Zeon, and JSR “ARTON” made by the manufacturer can be mentioned.

  The glass transition point (Tg) of the resin (A) is preferably 60 ° C. or higher. Particularly preferably, the glass transition point of the resin (A) is 70 ° C. or higher. When the glass transition point of the resin (A) is 60 ° C. or higher, softening of the adhesive layer can be further suppressed when the adhesive composition is exposed to a high temperature environment.

  The resin (B) is at least one resin selected from the group consisting of terpene resins, rosin resins and petroleum resins. Specifically, examples of the terpene resin include terpene resins, terpene phenol resins, modified terpene resins, hydrogenated terpene resins, hydrogenated terpene phenol resins, and the like. Examples of the rosin resin include rosin, rosin ester, hydrogenated rosin, hydrogenated rosin ester, polymerized rosin, polymerized rosin ester, and modified rosin. Examples of petroleum resins include aliphatic or aromatic petroleum resins, hydrogenated petroleum resins, modified petroleum resins, alicyclic petroleum resins, coumarone-indene petroleum resins, and the like. Among these, hydrogenated terpene resins and hydrogenated petroleum resins are preferable.

  Although the softening point of resin (B) is not specifically limited, It is preferable that it is 80-160 degreeC. When the softening point of the resin (B) is 80 ° C. or higher, the adhesive composition can be suppressed from being softened when exposed to a high temperature environment, and adhesion failure does not occur. On the other hand, when the softening point of the resin (B) is 160 ° C. or less, the peeling rate when peeling the adhesive composition becomes good.

  Although the molecular weight of resin (B) is not specifically limited, It is preferable that it is 300-3000. When the molecular weight of the resin (B) is 300 or more, the heat resistance is sufficient, and the degassing amount is reduced under a high temperature environment. On the other hand, when the molecular weight of the resin (B) is 3000 or less, the peeling rate when peeling the adhesive composition is good. In addition, the molecular weight of resin (B) in this embodiment means the molecular weight of polystyrene conversion measured by gel permeation chromatography (GPC).

  In addition, you may use what mixed resin (A) and resin (B) as resin. By mixing, heat resistance and peeling speed are improved. For example, the mixing ratio of the resin (A) and the resin (B) is (A) :( B) = 80: 20 to 55:45 (mass ratio). Since it is excellent in tolerance and flexibility, it is preferable.

(Acrylic-styrene resin)
Examples of the acryl-styrene resin include a resin obtained by polymerization using styrene or a styrene derivative and (meth) acrylic acid ester as monomers.

  As (meth) acrylic acid ester, (meth) acrylic acid ester has, for example, (meth) acrylic acid alkyl ester having a chain structure, (meth) acrylic acid ester having an aliphatic ring, and aromatic ring. (Meth) acrylic acid ester is mentioned. Examples of the (meth) acrylic acid alkyl ester having a chain structure include an acrylic long-chain alkyl ester having an alkyl group having 15 to 20 carbon atoms and an acrylic alkyl ester having an alkyl group having 1 to 14 carbon atoms. . As acrylic long-chain alkyl esters, acrylic or methacrylic acid whose alkyl group is n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosyl group, etc. Examples include alkyl esters. The alkyl group may be branched.

  Examples of the acrylic alkyl ester having an alkyl group having 1 to 14 carbon atoms include known acrylic alkyl esters used in existing acrylic adhesives. For example, an alkyl group of acrylic acid or methacrylic acid whose alkyl group is a methyl group, ethyl group, propyl group, butyl group, 2-ethylhexyl group, isooctyl group, isononyl group, isodecyl group, dodecyl group, lauryl group, tridecyl group, etc. Examples include esters.

  Examples of (meth) acrylic acid ester having an aliphatic ring include cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, 1-adamantyl (meth) acrylate, norbornyl (meth) acrylate, isobornyl (meth) acrylate, and tricyclodecanyl. (Meth) acrylate, tetracyclododecanyl (meth) acrylate, dicyclopentanyl (meth) acrylate and the like can be mentioned, and isobornyl methacrylate and dicyclopentanyl (meth) acrylate are more preferable.

  The (meth) acrylic acid ester having an aromatic ring is not particularly limited. Examples of the aromatic ring include a phenyl group, a benzyl group, a tolyl group, a xylyl group, a biphenyl group, a naphthyl group, and an anthracenyl group. A phenoxymethyl group, a phenoxyethyl group, and the like. The aromatic ring may have a chain or branched alkyl group having 1 to 5 carbon atoms. Specifically, phenoxyethyl acrylate is preferable.

(Maleimide resin)
Examples of maleimide resins include N-methylmaleimide, N-ethylmaleimide, Nn-propylmaleimide, N-isopropylmaleimide, Nn-butylmaleimide, N-isobutylmaleimide, N-sec as monomers. -Butylmaleimide, N-tert-butylmaleimide, Nn-pentylmaleimide, Nn-hexylmaleimide, Nn-heptylmaleimide, Nn-octylmaleimide, N-laurylmaleimide, N-stearylmaleimide, etc. Male having an aliphatic hydrocarbon group such as maleimide, N-cyclopropylmaleimide, N-cyclobutylmaleimide, N-cyclopentylmaleimide, N-cyclohexylmaleimide, N-cycloheptylmaleimide, N-cyclooctylmaleimide, etc. Resin obtained by polymerizing aromatic maleimide having an aryl group such as imide, N-phenylmaleimide, Nm-methylphenylmaleimide, N-o-methylphenylmaleimide, Np-methylphenylmaleimide, etc. It is done.

<Method for Preparing Adhesive Composition>
The adhesive composition according to this embodiment can be prepared by mixing the above-described resin and filler using a known method. As resin, you may use the solution (resin solution) diluted with the organic solvent as needed.

  Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, and 2-heptanone; ethylene glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate, dipropylene glycol Or polyhydric alcohols such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether of dipropylene glycol monoacetate and derivatives thereof; cyclic ethers such as dioxane; methyl lactate, ethyl lactate, methyl acetate , Ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, , And the like and terpene solvent, esters such as Tokishipuropion ethyl. These may be used alone or in combination of two or more.

  Examples of the terpene solvent include α-pinene, camphene, pinane, myrcene, dihydromyrcene, p-menthane, 3-carene, p-menthadiene, α-terpinene, β-terpinene, α-ferrandrene, osymene, limonene. , P-cymene, γ-terpinene, terpinolene, 1,4-cineole, 1,8-cineole, rose oxide, linalool oxide, Fencon, α-cyclocitral, osmenol, tetrahydrolinalol, linalool, tetrahydromegol, isopulegol, dihydro Linalool, isodihydrolabandulol, β-cyclocitral, citronellal, L-mentholone, linalyl formate, dihydroterpineol, β-terpineol, menthol, myrsenol, L-menthol, pinocarbeo , Α-terpineol, γ-terpineol, nopol, myrtenol, dihydrocarbeveol, citronellol, mirutenal, dihydrocarvone, d-pulegone, geranyl ethyl ether, geranyl formate, neryl formate, terpinyl formate, isodihydrolavanduril acetate, Terpinyl acetate, linalyl acetate, myrcenyl acetate, bornyl acetate, menthyl propionate, linalyl propionate, nerol, carveol, perilla alcohol, geraniol, safranal, citral, perilaaldehyde, citronellyloxyacetaldehyde, hydroxycitronellal, berbenone, d- Carvone, L-carvone, piperitone, piperitenone, citronellyl formate, isobornyl acetate, menthyl acetate, citronellyl acetate, carbyl acetate, acetic acid Dimethyloctanyl, neryl acetate, isopulegol acetate, dihydrocarbyl acetate, nopyr acetate, geranyl acetate, bornyl propionate, neryl propionate, carbyl propionate, terpinyl propionate, citronellyl propionate, isobornyl propionate, linalyl isobutyrate, isobutyric acid Examples include neryl, linalyl butyrate, neryl butyrate, terpinyl isobutyrate, terpinyl butyrate, geranyl isobutyrate, citronellyl butyrate, citronellyl hexanoate, menthyl isovalerate, β-caryophyllene, cedrene, bisabolen, hydroxycitronellol, farnesol and rosinyl isobutyrate. It is done. Among these, from the viewpoint of solubility, limonene and p-menthane are more preferable, and p-menthane is particularly preferable.

[Adhesive film]
The adhesive composition according to the present embodiment described above can employ various utilization methods depending on applications. For example, a method of forming an adhesive layer by applying onto a workpiece such as a semiconductor wafer while being in a liquid state may be used. A method in which an adhesive layer containing any of the above-described adhesive compositions is formed on a film and then dried, and this film (adhesive film) is used by being attached to a workpiece (adhesive film method) May be used.

  Thus, the adhesive film which concerns on this embodiment is equipped with the adhesive bond layer containing any adhesive composition mentioned above on a film. Therefore, since the softening temperature of the adhesive composition is high, delamination in a high temperature process can be suppressed.

  The adhesive film may be used by further covering the adhesive layer with a protective film. In this case, the protective film on the adhesive layer is peeled off, the exposed adhesive layer is stacked on the workpiece, and then the adhesive layer on the workpiece is easily removed by peeling the film from the adhesive layer. Can be provided.

  Therefore, if the adhesive film in the present embodiment is used, the film thickness uniformity and surface smoothness are good compared to the case where the adhesive composition is applied directly on the workpiece to form the adhesive layer. Various layers can be formed.

  In addition, as a film used for manufacturing an adhesive film, an adhesive layer formed on the film can be peeled off from the film, and the adhesive layer can be transferred onto a surface to be processed such as a protective substrate or a wafer. It is not limited as long as it is a mold film. For example, the flexible film which consists of synthetic resin films, such as a polyethylene terephthalate with a film thickness of 15-125 micrometers, polyethylene, a polypropylene, a polycarbonate, a polyvinyl chloride, is mentioned. If necessary, the film is preferably subjected to a release treatment so as to facilitate transfer.

  As a method for forming the adhesive layer on the film, a known method may be used as appropriate according to the desired film thickness and uniformity of the adhesive layer. Using a coater, a wire bar coater, a roll coater, a curtain flow coater, etc., a method of applying the adhesive composition according to the present invention so that the dry film thickness of the adhesive layer is 10 to 1000 μm on the film is mentioned. It is done. Among these, a roll coater is preferable because it is excellent in film thickness uniformity and a thick film can be efficiently formed.

  Moreover, when using a protective film, as a protective film, although not limited as long as it can peel from an adhesive bond layer, a polyethylene terephthalate film, a polypropylene film, and a polyethylene film are preferable, for example. Each protective film is preferably coated or baked with silicon from the viewpoint of facilitating peeling from the adhesive layer. Although the thickness of a protective film is not specifically limited, From a viewpoint of ensuring the softness | flexibility of the adhesive film provided with the protective film, 15-125 micrometers is preferable.

  The method of using the adhesive film is not particularly limited. For example, when a protective film is used, the adhesive layer exposed on the work piece is overlaid on the film after peeling it off. The method of thermocompression-bonding an adhesive bond layer to the surface of a to-be-processed body by moving a heating roller from (the back surface of the surface in which the adhesive bond layer was formed) is mentioned. At this time, the protective film peeled off from the adhesive film can be stored and reused by winding it in a roll with a winding roller or the like.

[Use of adhesive composition and adhesive film]
The use of the adhesive composition and the adhesive film of the present invention is not particularly limited as long as it is used for bonding wafers. It can be preferably used.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

(Preparation of adhesive composition)
A resin having adhesiveness was dissolved in p-menthane to obtain a resin solution having a resin solid content concentration of 30% by mass. Thereafter, a filler was added to the resin solution (based on the resin solid content) and mixed using a planetary mixer to prepare adhesive compositions in Examples 1 to 10.

As the filler, either filler 1 or filler 2 which is silicone particles was used. As the filler 1, a silicone resin powder (“KMP-701” (product name); a particle size of 3.5 μm, a particle size distribution of 1 to 6 μm, which is a three-dimensional cross-linked product of polyorganosilsessiloxane (RSi _3/2 ) _n , A heat resistance of 400 ° C. or higher, manufactured by Shin-Etsu Chemical Co., Ltd.) was used. As the filler 2, a silicone composite powder (“X-52-7030” (product name)) in which silicone is coated with a silicone resin; particle size 0.8 μm, particle size distribution 0.2 to 2 μm, heat resistance of 300 ° C. or higher, Shin-Etsu Chemical Co., Ltd.) was used.

  As the resin having adhesiveness, either resin 1 or resin 2 was used. As the resin 1, a cycloolefin copolymer (“TOPAS” (trade name) 8007, manufactured by Polyplastics Co., Ltd.) was used. As the resin 2, a cycloolefin copolymer (“APEL” (trade name) 8008, manufactured by Mitsui Chemicals, Inc.) was used.

  As the adhesive composition in the comparative example, resin 1 was used, and an adhesive composition containing no filler was prepared.

  The compositions of the adhesive compositions in Examples 1 to 10 and Comparative Example are shown in Table 1 below.

[Measurement of glass transition point and softening point]
Next, the glass transition point and softening point of each adhesive composition were measured.

Each adhesive composition was applied onto a 125 mm wafer, and then dried at 110 ° C., 150 ° C., and 200 ° C. for 3 minutes to form a coating film. The glass coating point (Tg) and softening point (SP) of the adhesive composition were measured using TMA (thermomechanical analyzer) for the formed coating film. As the measurement conditions, the load was 800 mN / cm ² , and the temperature elevation recipe was normal temperature to 200 ° C. (5 ° C./min). Under these conditions, the point at which the subduction starts was defined as the glass transition point, and the point at which the greater subduction began was defined as the softening point.

  FIGS. 1-6 is a graph which shows the measurement result using TMA about the adhesive composition in Example 3, 4, 7, 8, 9 or 10 of this invention, respectively. Moreover, FIG. 7 is a graph which shows the measurement result using TMA about the adhesive composition in the comparative example of this invention. The glass transition point and softening point obtained from these measurement results are shown in Table 2 below.

  As shown in Table 2, it was shown that the adhesive compositions of Examples 3, 4, 7, 8, 9 and 10 had a higher softening point and an improved softening temperature as compared with the comparative example. It was also shown that this effect can be obtained regardless of the type of resin used.

  Moreover, the measurement result (FIGS. 1-6) using TMA in the adhesive compositions of Examples 3, 4, 7, 8, 9, and 10 showed a behavior different from that of the comparative example (FIG. 7). In the adhesive compositions of Examples 3 and 4 including the filler 1 having a particle size of 3.5 μm, the sinking at 120 ° C. to 150 ° C. was slow.

  Further, in the adhesive compositions of Examples 7 and 8 including the filler 2 having a particle diameter of 0.8 μm, the sinking from room temperature to about 170 ° C. was small as compared with Comparative Examples and Examples 3 and 4. Therefore, it was suggested that the softening temperature is improved as the particle size of the filler contained in the adhesive composition is smaller.

[Measurement of stress]
Next, the stress (film stress) when each adhesive composition was used was measured.

  These adhesive compositions were applied onto a 125 mm wafer and dried at 110 ° C., 150 ° C., and 200 ° C. for 3 minutes each to form an adhesive layer, and then a glass substrate was adhered onto the adhesive layer. It was. Then, the stress in 23 degreeC was measured using the curvature and film | membrane stress measuring apparatus (FLX-2908, product made from KLA-Tencor).

  The results are shown in FIG. FIG. 8 is a graph showing the relationship between the filler content and stress when the adhesive composition in each example of the present invention is used. As shown in FIG. 8 and Table 3, especially when the adhesive composition (Examples 5 to 8) containing the filler 2 was used, the stress decreased as the filler content increased.

  Therefore, it was shown that stress can be relaxed and the amount of warpage of the wafer can be reduced by using an adhesive composition containing a filler. In particular, it has been found that the inclusion of 50% by weight or more of the filler provides a higher effect with respect to stress relaxation. It was also shown that the smaller the filler particle size, the higher the effect of relaxing the stress.

  The adhesive composition and adhesive film which concern on this invention can be used suitably for processing processes, such as a semiconductor wafer.

Claims (8)

An adhesive composition for bonding wafers,
An adhesive composition comprising a resin having adhesiveness and a filler.   2. The adhesive composition according to claim 1, wherein the content of the filler with respect to the resin is 20 wt% or more and 70 wt% or less.   The adhesive composition according to claim 1 or 2, wherein the filler has an average particle size of 0.5 µm or more and 5 µm or less.   The adhesive composition according to claim 1, wherein the filler is an inorganic filler.   The adhesive composition according to claim 1, wherein the filler has a heat resistance of 300 ° C. or higher.   The adhesive composition according to claim 1, wherein the resin is a hydrocarbon resin.   The adhesive composition according to claim 6, wherein the hydrocarbon resin is selected from the group consisting of a cycloolefin polymer, a terpene resin, a rosin resin, and a petroleum resin.   An adhesive film for adhering a wafer, comprising an adhesive layer containing the adhesive composition according to any one of claims 1 to 7 on the film.

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