JP2013030702A - Multilayer adhesive sheet for semiconductor device and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer adhesive sheet for a semiconductor device that has high ion trapping properties and high adhesion to an adhered body.SOLUTION: A multilayer adhesive sheet for a semiconductor device comprises an ion trapping layer formed from an ion trapping composition containing an organic low molecular weight compound forming a complex with a metal ion and an adhesion layer formed from an adhesive composition.

Description

  The present invention relates to a multilayer adhesive sheet for a semiconductor device, a semiconductor device in which a chip is laminated on an adherend by the multilayer adhesive sheet, and a method for manufacturing the semiconductor device.

  In recent years, a stacked MCP (Multi Chip Package) in which memory package chips for mobile phones and portable audio devices are stacked in multiple stages has become widespread. In addition, with the increasing functionality of image processing technology and mobile phones, etc., higher density, higher integration, and thinner packages are being promoted.

  On the other hand, when metal ions (for example, copper ions or iron ions) are mixed into the crystal substrate of the wafer from the outside during the semiconductor manufacturing process and reach the circuit formation surface formed on the wafer, the electrical characteristics There has been a problem of lowering. In addition, metal ions are generated from circuits and wires during use of the product, resulting in a problem that electrical characteristics are deteriorated.

  In order to solve the above-described problems, conventionally, an extrinsic gettering (hereinafter also referred to as “EG”) in which a rear surface of a wafer is processed to form a crushed layer (strain), and metal ions are captured and removed by the crushed layer. Intrinsic gettering (hereinafter also referred to as “IG”) in which oxygen precipitation defects are formed in the crystal substrate of the wafer and metal ions are captured and removed by the oxygen precipitation defects has been attempted.

  However, with the recent thinning of the wafer, the IG effect is reduced, and the backside distortion that causes the wafer to crack and warp is removed, so that the EG effect cannot be obtained and the gettering effect is improved. There was a problem that it could not be obtained sufficiently.

  As a method of capturing metal ions other than EG and IG, a method of adding an ion trapping agent or the like to an adhesive that fixes a semiconductor element to a substrate or the like has been proposed. Specifically, for example, a film adhesive having a copper ion adsorption layer containing a resin having a skeleton capable of complexing with copper ions (see, for example, Patent Document 1), ion exchange type or ion adsorption type ion trapping An adhesive sheet comprising an adhesive agent layer and a substrate (see, for example, Patent Documents 2 and 3), a film adhesive comprising an adhesive composition containing an ion trap agent comprising an inorganic compound (for example, a patent) Document 4), an adhesive sheet made of an adhesive composition containing an ion exchanger (for example, see Patent Document 5) and the like have been proposed.

  However, since the film-like adhesive of Patent Document 1 uses a resin as an ion scavenger, it is not sufficient in terms of ion trapping performance. In Patent Documents 2 to 5, the use of an organic low-molecular compound that forms a complex with a metal ion has not been studied at all.

JP 2011-052109 A JP 2009-203337 A JP 2009-203338 A JP 2010-116453 A JP 2009-256630 A

  The conventional adhesive sheet has the above-mentioned problems, and further, the chemical stability, chemical reactivity, physical properties, etc. of the adhesive sheet are changed by an ion scavenger such as a complexing agent, so that the substrate or the like is covered. There was room for improvement in that the adhesion to the body was lowered. Therefore, an object of the present invention is to provide a multilayer adhesive sheet for a semiconductor device having high ion trapping properties and high adhesion to an adherend.

  In order to solve the above problems, the present inventors have studied an adhesive sheet for a semiconductor device. As a result, the present invention is completed by finding that the above problems can be solved by forming a multilayer adhesive sheet for a semiconductor device including an ion trapping layer containing an organic low molecular weight compound complexed with a metal ion and an adhesive layer. It came to.

  That is, in the present invention, since it contains an ion trapping layer containing an organic low molecular weight compound that forms a complex with metal ions, it can be mixed into the crystal substrate of the wafer from the outside in various processes in the manufacture of semiconductor devices. Metal ions can be captured. As a result, it is difficult for metal ions mixed from the outside to reach the circuit formation surface formed on the wafer, and the deterioration of the electrical characteristics of the semiconductor device to be manufactured can be suppressed and the product reliability can be improved. Furthermore, since the multilayer adhesive sheet of the present invention has an adhesive layer separately from the ion trapping layer, it has excellent adhesion to an adherend such as a substrate.

  The organic low molecular weight compound is preferably one or more compounds selected from the group consisting of nitrogen-containing heterocyclic compounds and compounds having two or more hydroxyl groups in one aromatic ring.

  The ion-trapping composition and the adhesive composition preferably include a thermoplastic resin containing an epoxy group.

  It is preferable that the film thicknesses of the ion trapping layer and the adhesive layer are 5 to 100 μm, respectively.

  It is preferable that an organic low molecular weight compound is 0.1-10 weight part with respect to 100 weight part of all the components in an ion trapping layer.

  The ion-trapping composition contains a thermoplastic resin, a thermosetting resin, and a silica filler, and the thermoplastic resin is contained in 100 parts by weight of the total of the thermoplastic resin, the thermosetting resin, and the silica filler. It is preferable that it is 10-99 weight part, 1-30 weight part of thermosetting resins, and 0-60 weight part of silica fillers.

  The present invention also relates to a semiconductor device in which a chip is laminated on an adherend by the multilayer adhesive sheet, and a method for manufacturing the semiconductor device.

It is a cross-sectional schematic diagram of the multilayer adhesive sheet of this invention. It is a cross-sectional schematic diagram of the dicing die-bonding film which consists of the multilayer adhesive sheet and dicing film of this invention. It is a cross-sectional schematic diagram which shows the example which mounted the semiconductor chip through the multilayer adhesive sheet of this invention. It is a cross-sectional schematic diagram which shows the example which mounted the semiconductor chip three-dimensionally through the die-bonding film in the said dicing die-bonding film.

  As shown in FIG. 1, a multilayer adhesive sheet 1 for a semiconductor device according to the present invention includes an ion-trapping layer 1a formed from an ion-trapping composition containing an organic low-molecular compound that forms a complex with metal ions, and adhesiveness. It is a multilayer sheet including the adhesive layer 1b formed from the composition. In FIGS. 2-4, it shows as the multilayer adhesive sheet 1 in which these ion trapping layers 1a and adhesive layers 1b were integrated.

1. Ion-trapping layer The ion-trapping composition contains an organic low-molecular compound that forms a complex with a metal ion (hereinafter sometimes simply referred to as an organic low-molecular compound), and is formed from the composition. The multilayer adhesive sheet of the present invention having the above can capture metal ions mixed from the outside during various processes in the production of a semiconductor device. As a result, it is difficult for metal ions mixed from the outside to reach the circuit formation surface formed on the wafer, and a reduction in electrical characteristics can be suppressed to improve product reliability.

  In the present invention, the metal ion captured by the organic low molecular weight compound is not particularly limited as long as it is a metal ion. For example, Na, K, Ni, Cu, Cr, Co, Hf, Pt, Ca, Ba, Sr , Fe, Al, Ti, Zn, Mo, Mn, V, and the like.

  The organic low molecular weight compound that forms a complex with a metal ion used in the present invention is distinguished from a resin that can form a complex with a metal ion, and its molecular weight is preferably 1000 or less, preferably 500 or less. It is more preferable that The lower limit of the molecular weight is not particularly limited, but is usually 50 or more. In the said resin, the ratio of the functional group which contributes to the capture | acquisition of the metal ion in resin is low, As a result, complex formation with a metal ion becomes difficult. Therefore, a resin capable of forming a complex with a metal ion is not sufficient in terms of ion trapping properties. On the other hand, organic low molecular weight compounds having a molecular weight of 1000 or less tend to form complexes with metal ions because of the high proportion of functional groups that contribute to the capture of metal ions in one molecule, resulting in high ion trapping properties. It is considered to be.

  The organic low molecular weight compound is not particularly limited as long as it forms a complex with a metal ion, but from the viewpoint of suitably capturing a metal ion, a nitrogen-containing compound, a hydroxyl group-containing compound, a carboxyl group-containing compound It is preferably at least one selected from the group consisting of compounds, and is at least one compound selected from the group consisting of nitrogen-containing heterocyclic compounds and compounds having two or more hydroxyl groups in one aromatic ring. It is more preferable.

(Nitrogen-containing compounds)
The nitrogen-containing compound is preferably in the form of fine powder, easily dissolved in an organic solvent, or liquid. Further, the nitrogen-containing compound may be a compound having one or more nitrogen atoms in one molecule, but is preferably a compound having two or more nitrogen atoms in one molecule. As such a nitrogen-containing compound, a nitrogen-containing heterocyclic compound is preferable from the viewpoint of suitably capturing a metal ion, and a heterocyclic compound having a tertiary nitrogen atom as a ring constituent atom is more preferable. Here, the tertiary atom refers to a nitrogen atom of a tertiary amine.

  Examples of the nitrogen-containing heterocyclic compound include a triazole compound, a tetrazole compound, and a bipyridyl compound. Among these, a triazole compound is more preferable from the viewpoint of the stability of a complex formed with a copper ion. . These can be used alone or in combination of two or more.

  The triazole compound is not particularly limited, but 1,2,3-benzotriazole, 1- {N, N-bis (2-ethylhexyl) aminomethyl} benzotriazole, carboxybenzotriazole, 2- {2′-hydroxy -5'-methylphenyl} benzotriazole, 2- {2'-hydroxy-3 ', 5'-di-t-butylphenyl} -5-chlorobenzotriazole, 2- {2'-hydroxy-3'-t -Butyl-5'-methylphenyl} -5-chlorobenzotriazole, 2- {2'-hydroxy-3 ', 5'-di-t-amylphenyl} benzotriazole, 2- {2'-hydroxy-5' -T-octylphenyl} benzotriazole, 6- (2-benzotriazolyl) -4-t-octyl-6'-t-butyl-4 ' Methyl-2,2′-methylenebisphenol, 1- (2 ′, 3′-hydroxypropyl) benzotriazole, 1- (1 ′, 2′-dicarboxydiethyl) benzotriazole, 1- (2-ethylhexamino) Methyl) benzotriazole, 2,4-di-t-pentyl-6-{(1H-benzotriazol-1-yl) methyl} phenol, 2- (2-hydroxy-5-t-butylphenyl) -2H- Benzotriazole, 3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxy, octyl-3- [3-tert-butyl-4-hydroxy-5- (5) -Chloro-2H-benzotriazol-2-yl) phenyl] propionate, 2-ethylhexyl-3- [3-t-butyl-4-hydroxy-5- ( -Chloro-2H-benzotriazol-2-yl) phenyl] propionate, 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3 , 3-tetramethylbutyl) phenol, 2- (2H-benzotriazol-2-yl) -4-t-butylphenol, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2 ′ -Hydroxy-5'-t-octylphenyl) -benzotriazole, 2- (3'-t-butyl-2'-hydroxy-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy) -3 ', 5'-di-t-amylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'-di-t-butylphenyl) -5-chloro Rho-benzotriazole, 2- [2′-hydroxy-3,5-di (1,1-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2′-methylenebis [6- (2H-benzotriazole-2) -Yl) -4- (1,1,3,3-tetramethylbutyl) phenol], (2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole Methyl 3- (3- (2H-benzotriazol-2-yl) -5-t-butyl-4-hydroxyphenyl) propionate, 5-methyl-1H-benzotriazole and the like.

  Although it does not restrict | limit especially as a commercial item of the said triazole compound, Johoku Chemical Co., Ltd. brand name: BT-120, BT-LX, CBT-1, JF-77, JF-78, JF-79, JF -80, JF-83, JAST-500, BT-GL, BT-M, BT-260, BT-365, TT-LX, BASF trade names: TINUVIN PS, TINUVIN P, TINUVIN P FL, TINUVIN 99- 2, TINUVIN 109, TINUVIN 900, TINUVIN 928, TINUVIN 234, TINUVIN 329, TINUVIN 329 FL, TINUVIN 326, TINUVIN 326 FL, TINUVIN 571, TINUVIN 213, product name made by Yongkou Chemical Co., Taiwan: 81 EVESORB109, EVESORB 70, EVESORB 71, EVESORB 72, EVESORB 73, EVESORB 74, EVESORB 75, EVESORB 76, EVESORB 78, EVESORB 80, Daiwa Kasei Co., Ltd. trade name: VERZONE VT-120M and the like. Triazole compounds are also used as rust inhibitors.

  Although it does not specifically limit as said tetrazole compound, 5-amino-1H-tetrazole, 5-phenyl-1H-tetrazole, etc. are mentioned.

  Although it does not specifically limit as said bipyridyl compound, 2,2'-bipyridyl, 1, 10-phenanthroline etc. are mentioned.

(Hydroxyl-containing compound)
Although it does not restrict | limit especially as said hydroxyl-containing compound, The thing of a fine powder form, the thing easy to melt | dissolve in an organic solvent, or a liquid thing is preferable. Examples of such a hydroxyl group-containing compound include a quinol compound, a hydroxyanthraquinone compound, a polyphenol compound, and a higher alcohol from the viewpoint of more suitably capturing a metal ion, but a complex formed with a copper ion. From the viewpoint of stability, a compound having two or more hydroxyl groups in one aromatic ring is preferable, and a polyphenol compound is more preferable. These can be used alone or in combination of two or more.

  Although it does not specifically limit as said quinol compound, 1, 2- benzenediol etc. are mentioned.

  Although it does not specifically limit as said hydroxyanthraquinone compound, Alizarin, anthralfin, etc. are mentioned.

  Examples of the polyphenol compound include, but are not limited to, tannin, tannin derivatives (gallic acid, methyl gallate, dodecyl gallate, pyrogallol) and the like.

  Examples of the higher alcohol include alcohols having a linear or branched alkyl group having 6 or more carbon atoms, particularly 6 to 18 carbon atoms.

(Carboxyl group-containing compound)
Although it does not specifically limit as said carboxyl group containing compound, A carboxyl group containing aromatic compound, a carboxyl group containing fatty acid compound, etc. are mentioned.

  Although it does not specifically limit as said carboxyl group containing aromatic compound, A phthalic acid, picolinic acid, pyrrole-2-carboxylic acid, etc. are mentioned.

  The carboxyl group-containing fatty acid compound is not particularly limited, and examples thereof include higher fatty acids and carboxylic acid chelating reagents.

  Although it does not restrict | limit especially as a commercial item of the said carboxylic-acid type | system | group chelating reagent, The product name made from Cylest Co., Ltd. | , Kirest 0D, Kirest NTA, Kirest 700, Kirest PA, Kirest HA, Kirest MZ-2, Kirest MZ-4A, Kirest MZ-8.

  The amount of the organic low-molecular compound that forms a complex with the metal ion is preferably 0.1 to 10 parts by weight, based on 100 parts by weight of all components of the ion-trapping composition, and 0.1 to 5 parts by weight. Part is more preferable, 0.2 to 5 parts by weight is further preferable, and 0.3 to 3 parts by weight is particularly preferable. By setting it to 0.1 parts by weight or more, metal ions (particularly copper ions) can be effectively captured, and by setting it to 10 parts by weight or less, it is possible to suppress a decrease in heat resistance and an increase in cost. Can do. Moreover, the compounding quantity of the organic low molecular compound with respect to all the components in the ion trapping layer in the multilayer adhesive sheet of this invention is the same as the compounding quantity of the organic low molecular compound with respect to all the components in the said ion trapping composition.

  The ion-trapping composition preferably contains a thermoplastic resin, and more preferably contains a thermoplastic resin and a thermosetting resin.

  Examples of the thermosetting resin include a phenol resin, an amino resin, an unsaturated polyester resin, an epoxy resin, a polyurethane resin, a silicone resin, and a thermosetting polyimide resin. These resins can be used alone or in combination of two or more, and it is particularly preferable to use at least one of an epoxy resin and a phenol resin.

  The epoxy resin is not particularly limited as long as it is generally used as an adhesive composition. For example, bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF Type, biphenyl type, naphthalene type, fluorene type, phenol novolak type, orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., bifunctional epoxy resin or polyfunctional epoxy resin, or hydantoin type, trisglycidyl An isocyanurate type or glycidylamine type epoxy resin is used. These can be used alone or in combination of two or more. Among these epoxy resins, novolac type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type resins, or tetraphenylolethane type epoxy resins are particularly preferable.

  When the ion scavenging composition contains an epoxy resin, it is preferable to use a hydroxyl group or carboxyl group-containing resin in combination, and from the viewpoint of heat resistance, it is preferable to use a phenol resin in combination. Moreover, when the ion trapping composition contains a thermoplastic tree having an epoxy group, which will be described later, the phenol resin can react with the thermoplastic resin having the epoxy group. Examples of the phenol resin include phenol novolak resin, phenol aralkyl resin, cresol novolak resin, tert-butylphenol novolak resin, nonyl phenol novolak resin and other novolak type phenol resins, resol type phenol resin, and polyhydroxystyrene such as polyparahydroxystyrene. Etc. These can be used alone or in combination of two or more. Among these phenol resins, a phenol novolac resin and a phenol aralkyl resin are particularly preferable because the connection reliability of the semiconductor device can be improved.

  Further, the mixing ratio of the epoxy resin, the thermoplastic resin having an epoxy group, the hydroxyl group or carboxyl group-containing resin is not particularly limited. For example, the epoxy resin component or the thermoplastic resin component having an epoxy group It is preferable to blend so that the hydroxyl group in the hydroxyl group-containing resin component or the carboxyl group in the carboxyl group-containing resin component is 0.5 to 2.0 equivalents per equivalent of epoxy group in the group, 0.8 to 1.2 The equivalent is more preferable. It is preferable for the blending ratio to be within the above range since a sufficient reaction proceeds.

  The blending ratio of the thermosetting resin is preferably in the range of 1 to 30% by weight and more preferably in the range of 1 to 20% by weight in the ion-trapping composition.

  Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, heat Examples thereof include plastic polyimide resins, polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluorine resins. These thermoplastic resins can be used alone or in combination of two or more. Of these thermoplastic resins, an acrylic resin that has few ionic impurities and high heat resistance and can ensure the reliability of the semiconductor element is particularly preferable.

  The acrylic resin is not particularly limited, and includes one or two or more esters of acrylic acid or methacrylic acid having a linear or branched alkyl group having 30 or less carbon atoms, particularly 4 to 18 carbon atoms. Examples thereof include a polymer (acrylic copolymer) as a component. Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, heptyl group, cyclohexyl group, 2 -Ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, lauryl group, tridecyl group, tetradecyl group, stearyl group, octadecyl group, or dodecyl group.

  Further, the other monomer that forms the polymer is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Carboxyl group-containing monomers such as maleic anhydride or acid anhydride monomers such as itaconic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) acrylic acid 4 -Hydroxybutyl, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate or (4-hydroxymethylcyclohexyl) ) -Methyl Hydroxyl group-containing monomers such as acrylate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate or (meth) Sulfonic acid group-containing monomers such as acryloyloxynaphthalene sulfonic acid, or phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate, glycidyl acrylate, glycidyl methacrylate, 4-hydroxybutyl acrylate glycidyl ether, etc. And epoxy group-containing monomers. These can be used alone or in combination of two or more. The (meth) acrylic acid represents acrylic acid and / or methacrylic acid.

  In the present invention, it is preferable to use a thermoplastic tree having an epoxy group or a carboxyl group, from the viewpoint that the thermoplastic resin and the thermosetting resin are suitably cross-linked and good reliability is obtained. It is more preferable to use an acrylic resin having a carboxyl group or an acrylic resin having a carboxyl group. Examples of the acrylic resin having an epoxy group include a copolymer of an acrylic acid or methacrylic acid ester having an alkyl group and an epoxy group-containing monomer. Examples of the epoxy group-containing monomer include the same ones as described above. As a commercial item of the acrylic resin which has an epoxy group, Nagase ChemteX Co., Ltd. brand name: SG-P3 etc. can be mentioned. Moreover, as an acrylic resin which has a carboxyl group, the copolymer of the ester of acrylic acid or methacrylic acid which has the above-mentioned alkyl group, and carboxyl group-containing monomers, such as (meth) acrylic acid, is mentioned. As a commercial item of the acrylic resin which has a carboxyl group, Nagase ChemteX Co., Ltd. brand name: SG-708-6 etc. can be mentioned.

  The blending ratio of the thermoplastic resin is not particularly limited as long as the multilayer adhesive sheet exhibits a function as a thermosetting type when heated under predetermined conditions, but is 30 to 95 weight in the ion-trapping composition. %, Preferably in the range of 50 to 60% by weight.

  When the ion-trapping layer formed from the ion-trapping composition is crosslinked to some extent in advance, a polyfunctional compound that reacts with a functional group at the molecular chain end of the polymer is added as a crosslinking agent. Is good. Thereby, the adhesive property under high temperature can be improved and heat resistance can be improved.

  A conventionally well-known thing can be employ | adopted as said crosslinking agent. In particular, polyisocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, adducts of polyhydric alcohol and diisocyanate are more preferable. The addition amount of the crosslinking agent is not particularly limited, but for example, it is preferably 7 parts by weight or less with respect to 100 parts by weight of the polymer having a crosslinkable functional group, and 0.05 to 7 More preferred are parts by weight. When the amount of the cross-linking agent is more than 7 parts by weight, the adhesive force is lowered, which is not preferable. Moreover, you may make it include other polyfunctional compounds, such as an epoxy resin, together with such a polyisocyanate compound as needed.

  Moreover, a filler can be suitably mix | blended with the said ion-trapping composition according to the use. The blending of the filler enables imparting conductivity to the multilayer adhesive sheet including the ion trapping layer obtained from the ion trapping composition, improving thermal conductivity, adjusting the elastic modulus, and the like. Examples of the filler include inorganic fillers and organic fillers, and inorganic fillers are preferable from the viewpoints of characteristics such as improvement in handleability, improvement in thermal conductivity, adjustment of melt viscosity, and imparting thixotropic properties.

  The inorganic filler is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, and aluminum borate whisker. , Boron nitride, crystalline silica, amorphous silica and the like. These can be used alone or in combination of two or more. From the viewpoint of improving thermal conductivity, aluminum oxide, aluminum nitride, boron nitride, crystalline silica, and amorphous silica are preferable. Further, from the viewpoint that the above properties are well balanced, crystalline silica or amorphous silica is preferable. In addition, a conductive substance (conductive filler) may be used as the inorganic filler for the purpose of imparting conductivity and improving thermal conductivity. Examples of the conductive filler include metal powder in which silver, aluminum, gold, cylinder, nickel, conductive alloy and the like are made into a spherical shape, needle shape and flake shape, metal oxide such as alumina, amorphous carbon black, graphite and the like.

  The filler may have an average particle size of 0.005 to 10 μm. Adhesiveness can be made favorable by the average particle diameter of the said filler being 0.005 micrometer or more. Moreover, by setting it as 10 micrometers or less, while being able to make the effect of the filler added for provision of said each characteristic sufficient, heat resistance can be ensured. In addition, the average particle diameter of a filler is the value calculated | required, for example with the photometric type particle size distribution analyzer (The product made from HORIBA, apparatus name; LA-910).

  In addition to the said organic low molecular weight compound and the said filler, other additives can be suitably mix | blended with the said ion trapping composition as needed. Examples of other additives include an anion scavenger, a dispersant, an antioxidant, a silane coupling agent, and a curing accelerator. These can be used alone or in combination of two or more.

  The ion-trapping composition preferably includes a thermoplastic resin, a thermosetting resin, and a silica filler in addition to the organic low-molecular compound, and is a total of the thermoplastic resin, the thermosetting resin, and the silica filler. It is preferable that 10 to 99 parts by weight of the thermoplastic resin, 1 to 30 parts by weight of the thermosetting resin, and 0 to 60 parts by weight of the silica filler with respect to 100 parts by weight, and 20 to 20 parts of the thermoplastic resin. It is more preferable that 98 parts by weight, thermosetting resin is 2 to 30 parts by weight, and silica filler is 0 to 60 parts by weight. By being in the said range, since it can have a high elasticity modulus at high temperature and favorable reliability is obtained, it is preferable.

  The method for producing the ion-trapping composition is not particularly limited, and for example, an organic low-molecular compound that forms a complex with a metal ion, and if necessary, a thermosetting resin, a thermoplastic resin, and other additives. Is dissolved in an organic solvent and stirred so as to be uniform, whereby an ion-trapping composition solution can be obtained.

  The organic solvent is not particularly limited as long as it can uniformly dissolve, knead, or disperse the components constituting the ion trapping layer, and a conventionally known organic solvent can be used. Examples of such a solvent include ketone solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, acetone, methyl ethyl ketone, and cyclohexanone, toluene, xylene, and the like. Methyl ethyl ketone, cyclohexanone, and the like are preferably used because they have a high drying rate and can be obtained at low cost.

2. Adhesive layer The adhesive layer in the multilayer adhesive sheet of the present invention is formed from an adhesive composition. The adhesive composition is not particularly limited and can be used as long as it is an adhesive or the like used in this field. From the viewpoint of improving the adhesion to an adherend such as a substrate, the metal ion is used. It is preferable that the organic low molecular weight compound which forms a complex with is not substantially contained. Here, “substantially not containing” means that the organic low molecular weight compound is less than 0.1 parts by weight with respect to 100 parts by weight of the resin component of the adhesive composition. Less than 05 parts by weight, more preferably less than 0.01 parts by weight. Such an adhesive layer that does not substantially contain an organic low molecular weight compound does not proceed excessively even after heat is applied, and therefore occurs between an adherend such as a substrate and the adhesive layer. The voids can be diffused well in the molding process. In addition, since the low molecular weight compound has a low molecular weight, the organic low molecular weight compound easily migrates. When an adhesive sheet containing the low molecular weight organic compound is used as a die bond film of a dicing die bond film, the organic low molecular weight compound is dicing tape. There was a problem of moving to. However, since the multilayer adhesive sheet of the present invention has the adhesive layer, the organic low molecular weight compound can be prevented from transferring to the dicing tape.

  The composition other than the organic low-molecular compound that forms a complex with a metal ion can be the same composition as the above-described ion-trapping composition. Specifically, the adhesive composition can contain the aforementioned thermosetting resin, thermoplastic resin, filler, and other additives, and the blending ratio thereof is the same as that of the ion-trapping composition. . Moreover, the composition of the adhesive composition and the ion-trapping composition may be exactly the same or different except for the presence or absence of addition of an organic low-molecular compound that forms a complex with a metal ion.

  As the adhesive composition, those containing a thermoplastic resin, a thermosetting resin, and a silica filler are preferable, and the total amount of the thermoplastic resin, the thermosetting resin, and the silica filler is 100 parts by weight. Preferably, the plastic resin is 10 to 99 parts by weight, the thermosetting resin is 1 to 30 parts by weight, and the silica filler is 0 to 60 parts by weight, the thermoplastic resin is 20 to 98 parts by weight, and the thermosetting resin. Is more preferably 2 to 30 parts by weight and the silica filler is 0 to 60 parts by weight. By being in the said range, since it can have a high elasticity modulus at high temperature and favorable reliability is obtained, it is preferable.

3. Multilayer Adhesive Sheet The multilayer adhesive sheet of the present invention may have a two-layer structure composed of the ion trapping layer and the adhesive layer, and further between the ion trapping layer and the adhesive layer as long as the effects of the present invention are not impaired. Another layer may be included, and the ion scavenger layer may be provided on both sides of the adhesive layer.

  The multilayer adhesive sheet of the present invention is produced, for example, as follows. First, the ion-trapping composition solution is prepared. Next, after an ion-trapping composition solution is applied on a substrate separator so as to have a predetermined thickness to form a coating film, the coating film is dried under predetermined conditions. As the base material separator, polyethylene terephthalate (PET), polyethylene, polypropylene, or a plastic film or paper surface-coated with a release agent such as a fluorine-type release agent or a long-chain alkyl acrylate-type release agent can be used. Moreover, it does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 70 to 160 ° C. and the drying time is 1 to 5 minutes. Thereby, the ion trapping layer of the multilayer adhesive sheet of the present invention is obtained.

  Next, the adhesive composition solution is prepared, and an adhesive layer is prepared in the same manner as the ion trapping layer.

  The multilayer adhesive sheet of the present invention can be obtained by bonding the ion trapping layer and the adhesive layer thus obtained. Since these layers are sticky layers, they can be bonded by simply bonding them together, and if necessary, temperature and pressure can be applied, or bonding can be performed using a known adhesive. . The temperature and pressure conditions can be appropriately set depending on the ion trapping layer and adhesive layer used.

  The film thicknesses of the ion trapping layer and the adhesive layer may be the same or different and are each preferably 5 to 100 μm, more preferably 5 to 20 μm. A film thickness larger than 5 μm is preferable because it can be adhered to the adherend without voids.

  Since the multilayer adhesive sheet of the present invention has an ion trapping layer containing an organic low molecular weight compound that forms a complex with metal ions, it can trap metal ions mixed from outside during various processes in the manufacture of semiconductor devices. As a result, it becomes difficult for the mixed metal ions to reach the circuit formation surface formed on the wafer, and the deterioration of the electrical characteristics can be suppressed and the product reliability can be improved. In addition, since the multilayer adhesive sheet of the present invention has an adhesive layer that does not substantially contain the organic low molecular weight compound, it has good adhesion to an adherend such as a substrate, and between the adherend and the adhesive sheet. Since the voids generated in the substrate can be diffused in the molding process, the adhesion to the adherend can be improved.

  In the above embodiment, the case where a thermosetting resin or a thermoplastic resin is used as the main component to be contained in the ion-trapping composition or the adhesive composition has been described. Instead of the plastic resin, an inorganic adhesive component such as ceramic, cement, or solder may be included.

  The multilayer adhesive sheet of the present invention can be suitably used for manufacturing a semiconductor device. Specifically, a die bond film for fixing the semiconductor chip to an adherend such as a lead frame, a protective film for protecting the back surface of the semiconductor chip of the flip chip type semiconductor device, and a seal for sealing the semiconductor chip. What is used as a stop sheet is mentioned.

  When the multilayer adhesive sheet of the present invention is used as a die bond film, a semiconductor wafer (semiconductor chip) is laminated on the ion trapping layer 1a (FIG. 1) side, and a dicing film (or deposition) is placed on the adhesive layer 1b (FIG. 1) side. The body) is preferably laminated.

  The ion-trapping layer of the multilayer adhesive sheet was cut to a weight of 2.5 g, heated at 175 ° C. for 5 hours, then immersed in 50 mL of 10 ppm Cu (II) ion aqueous solution and left at 120 ° C. for 20 hours. After that, the Cu (II) ion concentration in the aqueous solution is preferably less than 9.8 ppm, more preferably 0 to 9.5 ppm, and even more preferably 0 to 9 ppm. By being in the said range, the metal ion mixed from the outside during the various processes in manufacture of a semiconductor device is caught more easily. As a result, metal ions mixed from the outside are less likely to reach the circuit forming surface formed on the wafer, and the deterioration of the electrical characteristics can be suppressed and the product reliability can be further improved.

4). BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a chip is stacked on an adherend by the multilayer adhesive sheet, and a method for manufacturing a semiconductor device including a step of stacking a chip on the adherend by the multilayer adhesive sheet. About. Hereinafter, an embodiment of a semiconductor device and a method for manufacturing the semiconductor device when the multilayer adhesive sheet of the present invention is used as a die bond film will be specifically described with reference to the drawings.

  Below, the manufacturing method of the semiconductor device using the dicing die-bonding film 2 by which the multilayer adhesive sheet 1 (henceforth the die-bonding film 1) of this invention was laminated | stacked on the conventionally well-known dicing film is demonstrated (FIG. 2). . The dicing film according to the present embodiment has a structure in which the pressure-sensitive adhesive layer 3 is laminated on the base material 4.

  First, as shown in FIG. 2, the semiconductor wafer 5 is pressure-bonded onto the semiconductor wafer attaching portion 1c on the ion trapping layer 1a side of the die bond film 1 in the dicing die bond film 2, and this is adhered and held and fixed. (Mounting process). This step is performed while pressing with a pressing means such as a pressure roll.

  Next, dicing of the semiconductor wafer 5 is performed. Thereby, the semiconductor wafer 5 is cut into a predetermined size and separated into individual pieces, and the semiconductor chip 6 is manufactured. Dicing is performed according to a conventional method from the circuit surface side of the semiconductor wafer 5, for example. Further, in this step, for example, a cutting method called full cut for cutting up to the dicing die-bonding film 2 can be adopted. It does not specifically limit as a dicing apparatus used at this process, A conventionally well-known thing can be used. Further, since the semiconductor wafer 5 is bonded and fixed by the dicing die-bonding film 2, chip chipping and chip jumping can be suppressed, and damage to the semiconductor wafer 5 can also be suppressed.

  In order to peel off the semiconductor chip adhered and fixed to the dicing die bond film 2, the semiconductor chip 6 is picked up. The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, a method of pushing up individual semiconductor chips 6 from the dicing die-bonding film 2 side with a needle and picking up the pushed-up semiconductor chips 6 with a pick-up device can be mentioned.

  Here, when the pressure-sensitive adhesive layer 3 is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 3 is irradiated with ultraviolet rays. Thereby, the adhesive force with respect to the die-bonding film 1 of the adhesive layer 3 falls, and peeling of the semiconductor chip 6 becomes easy. As a result, the pickup can be performed without damaging the semiconductor chip.

  Next, as shown in FIG. 3, the semiconductor chip 6 formed by dicing is die-bonded to the adherend 8 through the die-bonding film 1 (semiconductor wafer bonding portion 1c). In this case, the adhesive layer 1b side of the die bond film 1 is in contact with the adherend. Die bonding is performed by pressure bonding. The conditions for die bonding are not particularly limited, and can be set as necessary. Here, examples of the adherend 8 include a resin substrate, a lead frame, and a Si wafer.

  Next, a wire bonding step of electrically connecting the tip of the terminal portion (inner lead) of the adherend 8 and an electrode pad (not shown) on the semiconductor chip 6 with the bonding wire 9 is performed. As the bonding wire 9, for example, a gold wire, an aluminum wire, a copper wire or the like is used. The temperature at the time of wire bonding is 80 to 250 ° C, preferably 80 to 220 ° C. The heating time is several seconds to several minutes. The connection is performed by a combination of vibration energy by ultrasonic waves and pressure energy by pressurization while being heated so as to be within the temperature range. In addition, a wire bonding process is performed without thermosetting the die-bonding film 1 by heat processing.

  Since the die bond film 1 does not substantially contain an organic low molecular weight compound in the adhesive layer 1b, voids generated between the adherend and the adhesive layer are not excessively cured even by a thermal history in the wire bonding process. Can be removed in the molding process.

  Subsequently, a sealing process for sealing the semiconductor chip 6 with the sealing resin 7 is performed. This step is performed to protect the semiconductor chip 6 and the bonding wire 9 mounted on the adherend 8. This step is performed by molding a sealing resin with a mold. As the sealing resin 7, for example, an epoxy resin is used.

  In the mounting step, air bubbles are generally mixed in the interface between the adherend 8 and the adhesive layer 1b of the die bond film 1 or the like. In the main sealing step, the bubbles are diffused into the sealing resin 7 or the like by the pressure at the time of resin sealing or the like, and the influence is reduced. In addition, as above-mentioned, since the die-bonding film 1 does not contain an organic low molecular compound substantially in the contact bonding layer 1b, progress of the rapid hardening reaction by the heat history in the wire bonding process is suppressed. As a result, bubbles can be easily diffused in the sealing step, and peeling due to bubbles at the bonding interface can be prevented.

  Next, in the post-curing process, the sealing resin 7 that is insufficiently cured in the sealing process is completely cured. Even when the die bond film 1 is not thermally cured in the sealing process, the die bond film 1 is thermally cured together with the curing of the sealing resin 7 in this process, thereby allowing the adhesive fixing. Although the heating temperature in this process changes with kinds of sealing resin, it exists in the range of 165-185 degreeC, for example, and heating time is about 0.5 minute-8 hours.

  Moreover, as shown in FIG. 4, the multilayer adhesive sheet (die bond film) of this invention can be used suitably also when laminating | stacking a some semiconductor chip and carrying out three-dimensional mounting. In the case of the three-dimensional mounting shown in FIG. 4, first, at least one die bond film 1 cut out to have the same size as the semiconductor chip is attached on the adherend 8, and then the semiconductor chip 6 is attached via the die bond film 1. , Paste the wire bond side up. Next, the die bond film 1 (which may be the multilayer adhesive sheet of the present invention or another die bond film) is attached while avoiding the electrode pad portion of the semiconductor chip 6. Further, another semiconductor chip 10 is die-bonded on the die-bonding film 1 so that the wire-bonding surface is on the upper side.

  Next, a wire bonding process is performed. Thereby, each electrode pad in the semiconductor chip 6 and the other semiconductor chip 10 and the adherend 8 are electrically connected by the bonding wire 9. In addition, this process is implemented without passing through the heating process of the die-bonding film 1.

  Subsequently, a sealing step of sealing the semiconductor chip 6 and the like with the sealing resin 7 is performed, and the sealing resin is cured. Next, in the post-curing process, the sealing resin 7 that is insufficiently cured in the sealing process is completely cured.

  In the embodiment described above, the case where the multilayer adhesive sheet of the present invention is a die bond film has been described. However, the multilayer adhesive sheet is not particularly limited as long as it is used for manufacturing a semiconductor device. It may be a protective film for protecting the back surface of the semiconductor chip of the flip chip type semiconductor device, or a sealing sheet for sealing between the surface of the semiconductor chip of the flip chip type semiconductor device and the adherend.

  Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, the materials, blending amounts, and the like described in this example are not intended to limit the gist of the present invention only to those unless otherwise limited. In the following, “parts” means parts by weight.

Example 1
(Ion trapping layer)
The following (a) to (d) were dissolved in methyl ethyl ketone to obtain an ion-trapping composition solution having a concentration of 20% by weight.
(A) Acrylic resin having an epoxy group as a functional group (manufactured by Nagase ChemteX Corp., SG-P3, weight average molecular weight 850,000) 60 parts (b) phenol resin (Maywa Kasei Co., Ltd., trade name: MEH) -7851H) 5 parts (c) Silica filler (manufactured by Admatechs Co., Ltd., product name: SC-2050, average particle size: 0.5 μm) 35 parts (d) low molecular organic compound (manufactured by Daiwa Kasei Co., Ltd.) , Trade name: VERZONE VT-120M, chemical name: 5-methyl-1H-benzotriazole) 0.3 parts

  This ion-trapping composition solution was applied onto a release-treated film made of a polyethylene terephthalate film (thickness 50 μm) subjected to silicone release treatment as a release liner. Furthermore, an ion trapping layer having a thickness of 5 μm was produced by drying at 130 ° C. for 2 minutes.

(Adhesive layer)
An adhesive layer having a thickness of 10 μm was produced in the same procedure as described above except that (d) was changed to 0 part by weight.

(Production of multilayer adhesive sheet)
The produced ion-trapping layer and the adhesive layer were bonded together using a laminator at a temperature of 40 ° C., a pressure of 0.2 MPa, and a speed of 10 mm / second to produce a two-layer adhesive sheet.

Examples 2-10, Comparative Examples 1-4
A multilayer adhesive sheet was obtained in the same manner as in Example 1 except that the composition and film thickness were changed to the values shown in Table 1. In addition, the following organic low molecular weight compounds were used.

SG-708-6: manufactured by Nagase ChemteX Corporation, an acrylic resin having a carboxyl group as a functional group, a number average molecular weight of 700,000 g / mol, an acid value of 9 mgKOH / g
EPPN-501HY: manufactured by Nippon Kayaku Co., Ltd., tris (hydroxyphenyl) methane type epoxy resin, epoxy equivalent: 169 g / eq
Dodecyl gallate: manufactured by Tokyo Chemical Industry Co., Ltd. (trade name; dodecyl gallate)
BT-120: manufactured by Johoku Chemical Co., Ltd., 1,2,3-benzotriazole alizarin: manufactured by Tokyo Chemical Industry Co., Ltd. P5T: manufactured by Toyobo Co., Ltd., methyl 5-phenyl-1H-tetrazole gallate: Tokyo Chemical Industry 2,2'-bipyridyl manufactured by Tokyo Chemical Industry Co., Ltd.

The following evaluation was performed.
<Method for evaluating metal ion scavenging properties>
An evaluation sheet (thickness: 20 μm) was prepared using the ion-trapping composition used in the examples and comparative examples. 2.5 g of the evaluation sheet was cut out and heated at 175 ° C. for 5 hours into a crucible made of Teflon (registered trademark), and 50 mL of a 10 ppm Cu (II) ion aqueous solution was added. Then, it was left to stand at 120 degreeC for 20 hours in the constant temperature dryer (Espec Co., Ltd. product, PV-231). After taking out the evaluation sheet, the concentration (ppm) of Cu (II) ions in the aqueous solution was measured using ICP-AES (manufactured by SII Nanotechnology, SPS-1700HVR). The case where the Cu (II) ion concentration in the aqueous solution was less than 9.8 ppm was evaluated as ◯, and the case where it was 9.8-10 ppm was evaluated as x. The results are shown in Table 2.

<Presence / absence of void disappearance after resin sealing step>
By sticking to a 10 mm square semiconductor chip on the ion trapping layer side of the two-layered adhesive sheet obtained in the examples and comparative examples, respectively, at a temperature of 40 ° C., and sticking a BGA substrate on the adhesive layer side The semiconductor chip was mounted on the BGA substrate via each adhesive sheet. The mounting conditions were a temperature of 120 ° C., a pressure of 0.1 MPa, and 1 second.

  Next, the BGA substrate on which the semiconductor chip was mounted was heat-treated at 175 ° C. for 30 minutes with a dryer, and then packaged with a sealing resin (GE-100, manufactured by Nitto Denko Corporation). The sealing conditions were a heating temperature of 175 ° C. and 90 seconds.

  Subsequently, the sealed semiconductor device was cut with a glass cutter, and the cross section was observed with an ultrasonic microscope to measure the void area on the bonding surface of each adhesive sheet and the BGA substrate. The case where the void area was 20% or less with respect to the bonding area was rated as ◯, and the case where the void area was larger than 20% was marked as x. The results are shown in Table 2.

  In Examples 1-10, since it has an ion trapping layer containing an organic low molecular weight compound, it is thought that a metal ion can be trapped and the defect of a package can be suppressed. In addition, since it has an adhesive layer that does not substantially contain organic low molecular weight compounds, the mold does not progress excessively even after applying a thermal history (175 ° C x 1 hour) assuming die bonding and wire bonding. Voids can be diffused well in the process.

  In Comparative Example 1, since no organic low molecular weight compound is contained, metal ions cannot be captured and package defects cannot be suppressed. Moreover, in Comparative Examples 2-3, since the organic low molecular weight compound is contained in the adhesive layer, the curing proceeds excessively due to the thermal history (175 ° C. × 1 hour) assuming die bonding and wire bonding, which is favorable during molding. The void cannot be diffused.

1: Multilayer adhesive sheet of the present invention 1a: Ion-trapping layer 1b: Adhesive layer 1c: Semiconductor wafer pasting part 2: Dicing die bond film 3: Adhesive layer 4: Base material 5: Semiconductor wafer 6: Semiconductor chip 7: Sealing Stop resin 8: Substrate 9: Bonding wire 10: Other semiconductor chip

Claims (8)

  A multilayer adhesive sheet for a semiconductor device, comprising: an ion trapping layer formed from an ion trapping composition containing an organic low-molecular compound complexed with a metal ion; and an adhesive layer formed from an adhesive composition.   The multilayer adhesive sheet according to claim 1, wherein the organic low molecular weight compound is at least one compound selected from the group consisting of a nitrogen-containing heterocyclic compound and a compound having two or more hydroxyl groups in one aromatic ring.   The multilayer adhesive sheet of Claim 1 or 2 in which an ion-trapping composition and an adhesive composition contain the thermoplastic resin containing an epoxy group.   The multilayer adhesive sheet according to any one of claims 1 to 3, wherein the ion trapping layer and the adhesive layer each have a thickness of 5 to 100 µm.   The multilayer adhesive sheet according to any one of claims 1 to 4, wherein the content of the organic low molecular weight compound is 0.1 to 10 parts by weight with respect to 100 parts by weight of all components in the ion trapping layer.   The ion-trapping composition contains a thermoplastic resin, a thermosetting resin, and a silica filler, and the thermoplastic resin is contained in 100 parts by weight of the total of the thermoplastic resin, the thermosetting resin, and the silica filler. The multilayer adhesive sheet according to any one of claims 1 to 5, wherein 10 to 99 parts by weight, thermosetting resin is 1 to 30 parts by weight, and silica filler is 0 to 60 parts by weight.   A semiconductor device in which a chip is laminated on an adherend by the multilayer adhesive sheet according to claim 1.   A method for manufacturing a semiconductor device, comprising a step of laminating a chip on an adherend by the multilayer adhesive sheet according to claim 1.

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