JP5897839B2 - Semiconductor device - Google Patents

Description

  The present invention relates to a 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 cations (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 these cations reach the circuit formation surface formed on the wafer, the electrical characteristics There has been a problem of lowering. In addition, there is a problem that cations are generated from circuits and wires during use of the product, resulting in deterioration of electrical characteristics.

  In order to solve the above-described problems, conventionally, an extrinsic gettering (hereinafter also referred to as “EG”) in which a back surface of a wafer is processed to form a crushed layer (strain) and a cation is 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 cations 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.

  Patent Document 1 describes a film adhesive provided with a copper ion adsorption layer containing a resin having a skeleton capable of complexing with copper ions. In addition, it is described that copper ions can be chemically adsorbed inside the resin of the copper ion adsorption layer, and the influence of copper ions generated from a member made of copper can be significantly reduced as compared with the conventional case. ing. Patent Documents 2 and 3 describe an adhesive composition containing an ion scavenger, and it is disclosed that this ion scavenger has an effect of capturing chlorine ions and the like. Patent Document 4 describes a film adhesive containing an ion trapping agent, and describes that the ion trapping agent captures a halogen element. Patent Document 5 describes an adhesive sheet containing an anion exchanger. Patent Document 6 describes a sheet-like adhesive containing a chelate-modified epoxy resin and capable of capturing internal ionic impurities.

JP 2011-52109 A JP 2009-203337 A JP 2009-203338 A JP 2010-116453 A JP 2009-256630 A JP 2011-105875 A

  The film adhesives of Patent Documents 2 to 5 do not disclose capturing cations. Therefore, it is difficult to prevent a decrease in electrical characteristics based on cations only by capturing chloride ions.

  Moreover, according to the film adhesive of patent document 1, and the sheet adhesive of patent document 6, a copper ion can be capture | acquired. On the other hand, when the film-like adhesive is attached to the semiconductor chip so that a part of the bonding wire is embedded in the film-like adhesive, it is necessary to consider the influence of cations generated from the bonding wire.

  In recent years, a bonding wire made of copper has been used. However, the copper wire has a problem that surface oxidation due to heat easily occurs and the bonding property is poor. For such problems, measures such as surface coating of palladium are taken.

  In recent years, with higher integration of semiconductor devices, bonding with a narrower pitch and bonding with a smaller area is required. However, since the copper wire has a relatively hard property, even if a measure such as coating the surface of palladium is adopted, the electrode may be damaged, and a bonding failure may occur due to this damage. Therefore, there is a problem of lacking long-term reliability. Moreover, when using a copper wire, there exists a problem that it is necessary to use the mixed gas of hydrogen and nitrogen which has attention in handling. Moreover, since the ultrasonic wave application time at the time of bonding is relatively long, there is room for improvement in terms of poor productivity. Therefore, in recent years, it has been studied to use silver wires instead of copper wires. Silver wire has high bondability, and there is an advantage that the gas used at the time of bonding may be only cheap and safe nitrogen gas. However, silver wires have a problem in long-term reliability in that they tend to cause ion migration at high temperatures and high humidity. References 1 to 6 do not disclose the adoption of a silver wire as a bonding wire, nor do they disclose capturing silver ions or suppressing the generation of silver ions.

  The present invention has been made in view of the above problems, and an object thereof is to provide a semiconductor device capable of preventing ion migration due to silver and ensuring long-term reliability.

  The inventors of the present application have studied a semiconductor device having an adhesive layer and a bonding wire in order to solve the conventional problems. As a result, by adopting the following configuration, it is possible to suppress ion migration due to silver mixed from the outside during various processes and silver contained in materials such as fillers and wires, ensuring long-term reliability. It has been found that it is possible to complete the present invention.

  That is, the semiconductor device according to the present invention is a semiconductor device having an adhesive layer and a bonding wire, wherein a part of the bonding wire is embedded in the adhesive layer and used for the adhesive layer. The adhesive sheet has a silver ion concentration of 0 to 9.9 ppm after immersing an adhesive sheet having a weight of 2.5 g in 50 ml of an aqueous solution containing 10 ppm of silver ions and leaving it at 120 ° C. for 20 hours. It is characterized by being.

  According to the said structure, the adhesive sheet used for an adhesive bond layer is the said aqueous solution after immersing a 2.5-g adhesive sheet in 50 ml of aqueous solution which has 10 ppm of silver ions, and leaving it to stand at 120 degreeC for 20 hours. The silver ion concentration in it is 0 to 9.9 ppm. Therefore, silver ions mixed from the outside during various processes in manufacturing the semiconductor device and silver ions generated from the bonding wires are trapped in the adhesive layer. As a result, it becomes difficult for silver 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. Moreover, since silver ions are trapped in the adhesive layer, ion migration of silver ions can be suppressed.

  In the said structure, the chloride ion density | concentration in the said aqueous solution after immersing an adhesive sheet | seat with a weight of 2.5g in 50 ml of ion-exchange water and leaving it to stand at 120 degreeC for 20 hours is 0.1 ppm or less. Is preferred. When chloride ions are present, the generation of cations is promoted. However, in the above configuration, the concentration of chloride ions in the aqueous solution after the operation is 0.1 ppm or less. Promotion is suppressed. That is, according to the above configuration, since the promotion of the generation of cations is suppressed, the deterioration of the electrical characteristics of the semiconductor device can be further suppressed and the product reliability can be improved.

  In the above configuration, the bonding wire can be any of gold, silver, and copper. However, when the bonding wire is made of silver, silver ions are likely to be generated from the bonding wire. However, in the case of the adhesive sheet, silver ions generated from the bonding wire are captured in the adhesive layer. As a result, it becomes difficult for silver 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. Further, since silver ions are trapped in the adhesive layer, ion migration of silver ions can be suppressed.

In recent years, there has been a demand for thinner, higher heat radiating and higher heat resistance packages due to the increase in heat generation and heat density due to downsizing, higher density, and higher integration of semiconductor devices. In many cases, conductive adhesive is used instead of silver paste. Among them, silver filler is often used as a conductive agent, but ion migration is likely to occur, causing a decrease in reliability. It is necessary to reduce silver ions that easily undergo ion migration.
The said structure WHEREIN: Although the filler contained in the adhesive sheet used for the said adhesive bond layer is not specifically limited, A remarkable effect is acquired when a silver filler is contained. When the adhesive sheet contains a silver filler, a package with high heat dissipation and high heat resistance can be obtained. However, when a silver filler is used, ion migration may easily occur. However, when the adhesive sheet is used, silver ions are trapped in the adhesive sheet. That is, according to the said structure, the ion migration by a silver filler can be suppressed, ensuring high heat dissipation and high heat resistance.

  The said structure WHEREIN: It is preferable that the adhesive sheet used for the said adhesive bond layer contains the ion trapping agent which capture | acquires a cation at least. When the adhesive sheet contains an ion scavenger that captures at least cations, cations can be captured more efficiently.

  The said structure WHEREIN: It is preferable that the said ion trapping agent is an organic type complex formation compound which forms a complex with a cation. When the ion scavenger is an organic complex-forming compound that forms a complex with a cation, since it is organic, damage to the bonding wire due to contact with the bonding wire can be suppressed.

  In the said structure, from a viewpoint which can capture | acquire a cation more suitably, the said organic type complex formation compound shall be 1 or more types chosen from the group which consists of a nitrogen-containing compound, a hydroxyl-containing compound, and a carboxylic acid group containing compound. preferable.

It is a cross-sectional schematic diagram which shows the semiconductor device which concerns on this embodiment. It is a cross-sectional schematic diagram for demonstrating the manufacturing method of the semiconductor device which concerns on this embodiment. It is a cross-sectional schematic diagram for demonstrating the manufacturing method of the semiconductor device which concerns on this embodiment. It is a cross-sectional schematic diagram for demonstrating the manufacturing method of the semiconductor device which concerns on this embodiment. It is a top view which shows typically the comb-type electrode used for HAST-proof evaluation.

  Embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these examples. In the drawings, parts unnecessary for explanation are omitted, and there are parts shown enlarged or reduced for easy explanation. In the following, first, the semiconductor device according to the present embodiment will be described.

  FIG. 1 is a schematic cross-sectional view showing the semiconductor device according to the present embodiment. As shown in FIG. 1, a semiconductor device 50 according to the present embodiment includes an adherend 6, a semiconductor chip 16 attached on the adherend 6 via a die bond film 13, and an adhesive on the semiconductor chip 16. And a semiconductor chip 5 attached via a sheet 3. The tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 5 are electrically connected (wire bonded) by a bonding wire 7. In addition, the tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 16 are electrically connected (wire bonded) by a bonding wire 7. In the vicinity of the electrode pad of the semiconductor chip 16, a part of the bonding wire 7 is embedded in the adhesive sheet 3. The bonding wire 7 is made of silver. The members mounted on the adherend 6 including the semiconductor chip 5, the semiconductor chip 16, the bonding wire 7, the die bond film 13, and the adhesive sheet 3 are sealed with a sealing resin 8. In the present embodiment, a semiconductor device 50 having a two-layer structure in which the semiconductor chip 5 is stacked on the semiconductor chip 16 will be described. However, in the semiconductor device according to the present invention, a part of the bonding wire is in the adhesive layer. As long as it has an embedded configuration, it is not limited to this example. For example, the semiconductor device of the present invention may have a configuration in which three or more semiconductor chips are stacked.

  The adhesive sheet 3 has a silver ion concentration of 0-9. After immersing an adhesive sheet having a weight of 2.5 g in 50 ml of an aqueous solution containing 10 ppm of silver ions and leaving it at 120 ° C. for 20 hours. 9 ppm, preferably 0 to 9.5 ppm, and more preferably 0 to 9.0 ppm. The adhesive sheet 3 has a silver ion concentration of 0 to 9.9 ppm after the adhesive sheet having a weight of 2.5 g is immersed in 50 ml of an aqueous solution having 10 ppm of silver ions and left at 120 ° C. for 20 hours. Therefore, silver ions mixed from the outside during various processes in manufacturing the semiconductor device and silver ions generated from the bonding wire 7 are captured in the adhesive sheet 3. As a result, it becomes difficult for silver ions to reach the circuit formation surface formed on the wafer (semiconductor chip 16), and the deterioration of the electrical characteristics can be suppressed and the product reliability can be improved. Moreover, since silver ion is trapped in the adhesive sheet 3, ion migration of silver ion can be suppressed.

  The adhesive sheet 3 has a chloride ion concentration in the aqueous solution of 0.1 ppm or less after immersing an adhesive sheet weighing 2.5 g in 50 ml of ion-exchanged water and leaving it at 120 ° C. for 20 hours. Is preferred. When chloride ions are present, the generation of cations is promoted. However, when the chloride ion concentration in the aqueous solution after the operation is 0.1 ppm or less, the promotion of the generation of cations is suppressed. The That is, when the chloride ion concentration is 0.1 ppm or less, since the promotion of cation generation is suppressed, the deterioration of the electrical characteristics of the semiconductor device 50 can be further suppressed and the product reliability can be improved. it can.

  The adhesive sheet 3 preferably contains at least an additive that captures cations (hereinafter also referred to as an ion scavenger). When an ion scavenger is contained, cations mixed from outside during various processes in manufacturing the semiconductor device 50 and cations generated from the bonding wire 7 can be captured. As a result, the cations mixed from the outside and the cations generated from the bonding wire 7 are difficult to reach the circuit forming surface formed on the wafer (semiconductor chip 16), and the deterioration of electrical characteristics is suppressed. Reliability can be improved.

  Examples of the ion scavenger include cation exchangers and complex forming compounds. Among these, a cation exchanger is preferable from the viewpoint of excellent heat resistance, and a complex-forming compound is more preferable from the viewpoint that cations can be captured well.

  The cation exchanger is preferably an inorganic cation exchanger from the viewpoint that it can capture cations more suitably.

  In the present invention, the cation captured by the ion scavenger is not particularly limited as long as it is a cation. For example, Na, K, Ni, Ag, Cu, Cr, Co, Hf, Pt, Ca, Ba, Examples include ions such as Sr, Fe, Al, Ti, Zn, Mo, Mn, and V.

(Inorganic cation exchanger)
The inorganic cation exchanger is not particularly limited, and a conventionally known inorganic cation exchanger can be used.For example, from the viewpoint of capturing a cation more suitably, antimony, bismuth, zirconium, titanium, An oxide hydrate of an element selected from the group consisting of tin, magnesium and aluminum can be mentioned. These can be used alone or in combination of two or more. Of these, oxidized hydrates of magnesium and aluminum are preferable.

  As a commercial item of the said inorganic cation exchanger, Toa Gosei Co., Ltd. brand names: IXE-700F, IXE-770, IXE-770D, IXE-2116, IXE-100, IXE-300, IXE-600, IXE -633, IXE-6107, IXE-6136, and the like.

  The average particle size of the inorganic cation exchanger is preferably 0.05 to 20 μm, and more preferably 0.1 to 10 μm. By setting the average particle size of the inorganic cation exchanger to 20 μm or less, it is possible to suppress a decrease in adhesive force, and by setting the average particle size to 0.05 μm or more, it is possible to improve dispersibility.

(Complex-forming compound)
The complex-forming compound is not particularly limited as long as it forms a complex with a cation. From the viewpoint of suppressing damage to the bonding wire due to contact with the bonding wire, the organic complex It is preferably a forming compound, and among these, from the viewpoint that a cation can be suitably captured, it is preferably at least one selected from the group consisting of a nitrogen-containing compound, a hydroxyl group-containing compound, and a carboxylic acid group-containing compound.

(Nitrogen-containing compounds)
The nitrogen-containing compound is preferably in the form of fine powder, easily dissolved in an organic solvent, or liquid. Examples of such nitrogen-containing compounds include triazole compounds, tetrazole compounds, and bipyridyl compounds from the viewpoint of more suitably capturing cations, but the stability of complexes formed with copper ions. In view of the above, a triazole compound is more preferable. 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-benzyl-6-{(H-benzotriazol-1-yl) methyl} phenol, 2- (2-hydroxy-5-t-butylphenyl) -2H-benzo Triazole, 3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxy, octyl-3- [3-t-butyl-4-hydroxy-5- (5- Chloro-2H-benzotriazol-2-yl) phenyl] propionate, 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy-5- (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 -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-metramethylbutyl) phenol], (2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, And methyl 3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate.

  Although it does not restrict | limit especially as a commercial item of the said triazole compound, The brand name made from Johoku Chemical Co., Ltd .: BT-120, BT-LX, CBT-1, JF-77, JF-78, JF-79, JF- Product names of 80, JF83, JAST-500, BT-GL, BT-M, BT-260, BT-365, BASF: 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, Taiwan Yongkou Chemical Co., Ltd. Product names: EVESORB 81, EVES RB109, EVESORB 70, EVESORB 71, EVESORB 72, EVESORB 73, EVESORB 74, EVESORB 75, can be cited EVESORB 76, EVESORB 78, EVESORB 80 or the like. Triazole compounds are also used as rust inhibitors.

  Although it does not specifically limit as said tetrazole compound, 5-amino-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. As such a hydroxyl group-containing compound, a quinol compound, a hydroxyanthraquinone compound, or a polyphenol compound can be exemplified from the viewpoint of more suitably capturing a cation, but the stability of a complex formed with a copper ion can be exemplified. From the viewpoint of properties, 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.

  Although it does not specifically limit as said polyphenol compound, A tannin, a tannin derivative (gallic acid, methyl gallate, pyrogallol) etc. are mentioned.

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

  The carboxyl group-containing aromatic compound is not particularly limited, and examples thereof include phthalic acid, picolinic acid, and pyrrole-2-carboxylic acid.

  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 Kyrest Co., Ltd .: Kyrest A, Kyrest 110, Kyrest B, Kyrest 200, Kyrest C, Kyrest D, Kyrest 400, Kyrest 40, Examples include Kirest 0D, Kirest NTA, Kirest 700, Kirest PA, Kirest HA, Kirest MZ-2, Kirest MZ-4A, and Kirest MZ-8.

  The content of the ion scavenger is preferably 0.1 to 80 parts by weight, and more preferably 0.1 to 50 parts by weight with respect to 100 parts by weight of the resin component constituting the adhesive sheet. More preferably, it is 0.1 to 20 parts by weight. By setting the amount to 0.1 parts by weight or more, cations (particularly copper ions) can be effectively captured, and by setting the amount to 80 parts by weight or less, a decrease in heat resistance and an increase in cost are suppressed. Can do.

  The adhesive sheet preferably has a melt viscosity at 140 ° C. of 10 Pa · s or more and 5000 Pa · s or less, and more preferably 10 Pa · s or more and 2000 Pa · s or less before thermosetting. When the melt viscosity at 140 ° C. before thermosetting is 10 Pa · s or more, the bonding wire can be suitably embedded in an adhesive sheet for manufacturing a semiconductor device. Moreover, a wire can be favorably embedded as the melt viscosity at 140 ° C. before thermosetting is 5000 Pa · s or less. The melt viscosity at 140 ° C. before thermosetting is the weight average molecular weight of the thermoplastic resin, the glass transition temperature of the thermoplastic resin, the ratio of the filler to the adhesive sheet, the size of the filler, the shape of the filler, and the thermoplastic resin and thermosetting. It can be controlled by the weight composition ratio of the functional resin. The melt viscosity can be measured by a parallel plate method using a rheometer (manufactured by HAAKE, trade name: RS-1). That is, 0.1 g of an adhesive sheet is charged into a plate heated to 120 ° C. and measurement is started. The average value after 240 seconds from the start of measurement is taken as the melt viscosity. The gap between the plates is 0.1 mm.

  The adhesive sheet preferably has a tensile storage elastic modulus at 260 ° C. of 0.5 MPa or more after being heat-cured at 175 ° C. for 5 hours after heat treatment at 120 ° C. for 1 hour, and 0.5 MPa or more and 1000 MPa or less. It is more preferable that Reflow resistance can be improved as the tensile storage elastic modulus at 260 ° C. after thermosetting is 0.5 MPa or more. Moreover, it can suppress that peeling arises between an adhesive sheet and a to-be-adhered body at the time of reflow as the tensile storage elastic modulus in 260 degreeC after thermosetting is 1000 Mpa or less. The tensile storage modulus can be measured, for example, by using a solid viscoelasticity measuring device (Rheometric Scientific, type: RSA-III). That is, the sample size is 400 mm long × 10 mm wide × 200 μm thick, and the measurement sample heat-cured at 120 ° C. for 1 hour and thermally cured at 175 ° C. for 5 hours is set in a film tensile measurement jig, and −50 By measuring the tensile storage elastic modulus and loss elastic modulus in a temperature range of ˜300 ° C. under conditions of a frequency of 1 Hz and a heating rate of 10 ° C./min, and reading the storage elastic modulus (E ′) at 260 ° C. can get.

  Although the said adhesive sheet is not specifically limited, It is preferable that a film thickness is 1-200 micrometers, and it is more preferable that it is 1-150 micrometers. By setting the film thickness of the adhesive sheet to 1 μm or more, cations can be captured more favorably.

  The adhesive sheet preferably contains a thermoplastic resin. Moreover, it is preferable that the said adhesive sheet contains a thermoplastic resin and a thermosetting resin. Examples of the thermosetting resin include phenol resin, amino resin, unsaturated polyester resin, epoxy resin, polyurethane resin, silicone resin, and 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. Among these, it is preferable to use an epoxy resin. When an epoxy resin is contained as a curing agent, a high adhesive force between the adhesive sheet and the wafer can be obtained at a high temperature. As a result, it is difficult for water to enter the adhesive interface between the adhesive sheet and the wafer, making it difficult for ions to move. Thereby, reliability is improved.

  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 novolac type, orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., bifunctional epoxy resin or polyfunctional epoxy resin, or hydantoin type, trisglycidyl isocyanurate Type or glycidylamine type epoxy resin is used. These can be used alone or in combination of two or more. Of these epoxy resins, novolac type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type resins or tetraphenylolethane type epoxy resins are particularly preferred. This is because these epoxy resins are rich in reactivity with a phenol resin as a curing agent and are excellent in heat resistance and the like. Moreover, it is preferable to employ | adopt what has little content of chloride ion as an epoxy resin. If such an epoxy resin is employed, even if an ion scavenger that cannot capture chloride ions is used, an adhesive sheet having a weight of 2.5 g is immersed in 50 ml of ion-exchanged water at 120 ° C. The chloride ion concentration in the aqueous solution after being left for 20 hours can be 0.1 ppm or less.

  Further, the phenol resin acts as a curing agent for the epoxy resin, for example, a novolac type phenol resin such as a phenol novolac resin, a phenol aralkyl resin, a cresol novolac resin, a tert-butylphenol novolac resin, a nonylphenol novolac resin, Examples include resol-type phenolic resins and polyoxystyrenes such as polyparaoxystyrene. These can be used alone or in combination of two or more. Of these phenol resins, phenol novolac resins and phenol aralkyl resins are particularly preferred. This is because the connection reliability of the semiconductor device can be improved.

  The mixing ratio of the epoxy resin and the phenol resin is preferably such that, for example, the hydroxyl group in the phenol resin is 0.5 to 2.0 equivalents per 1 equivalent of the epoxy group in the epoxy resin component. . More preferred is 0.8 to 1.2 equivalents. That is, if the blending ratio of both is out of the above range, sufficient curing reaction does not proceed and the properties of the cured epoxy resin are likely to deteriorate.

  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 a 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- Examples include an ethylhexyl group, an octyl group, an isooctyl group, a nonyl group, an isononyl group, a decyl group, an isodecyl group, an undecyl group, a lauryl group, a tridecyl group, a tetradecyl group, a stearyl group, an octadecyl group, and a dodecyl group.

  In addition, the other monomer forming 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 acid anhydride monomers such as maleic anhydride or itaconic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4- (meth) acrylic acid 4- Hydroxybutyl, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate or (4-hydroxymethylcyclohexyl) -Methyla Hydroxyl group-containing monomers such as relate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate or (meth) Examples thereof include sulfonic acid group-containing monomers such as acryloyloxynaphthalene sulfonic acid, and phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate. These can be used alone or in combination of two or more.

  The blending ratio of the thermosetting resin is not particularly limited as long as the adhesive sheet exhibits a function as a thermosetting mold when heated under predetermined conditions, but is in the range of 5 to 60% by weight. It is preferable that it is in the range of 10 to 50% by weight.

  Among the adhesive sheets, an epoxy resin, a phenol resin, and an acrylic resin are contained, and the total amount of the epoxy resin and the phenol resin with respect to 100 parts by weight of the acrylic resin is preferably 10 to 2000 parts by weight. It is more preferably ˜1500 parts by weight, and further preferably 10 to 1000 parts by weight. By making the total amount of the epoxy resin and the phenol resin with respect to 100 parts by weight of the acrylic resin 10 parts by weight or more, an adhesive effect due to curing can be obtained, and peeling can be suppressed. It is possible to suppress the workability from being deteriorated due to the weakening of the film.

  When the adhesive sheet is previously crosslinked to some extent, it is preferable to add a polyfunctional compound that reacts with a functional group at the molecular chain end of the polymer as a crosslinking agent. 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 usually preferably 0.05 to 7 parts by weight with respect to 100 parts by weight of the polymer. When the amount of the cross-linking agent is more than 7 parts by weight, the adhesive force is lowered, which is not preferable. On the other hand, if it is less than 0.05 parts by weight, the cohesive force is insufficient, 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 appropriately blended in the adhesive sheet according to its use. The blending of the filler enables imparting electrical conductivity to the adhesive sheet, 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 0.01 to 10 μm. By setting the average particle size of the filler to 0.01 μm or more, the wettability to the adherend and the adhesiveness can be improved. 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 ion scavenger, other additives can be appropriately blended in the adhesive sheet as necessary. 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 production method of the adhesive composition for forming the adhesive sheet is not particularly limited, and for example, the thermosetting resin, the thermoplastic resin, and the ion scavenger, and other, if necessary. Can be obtained as an adhesive composition solution by adding the above additives and the like into a container, dissolving them in an organic solvent, and stirring them uniformly.

  The organic solvent is not particularly limited as long as it can uniformly dissolve, knead or disperse the components constituting the adhesive sheet, and a conventionally known one 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.

  The adhesive sheet according to the present embodiment is produced, for example, as follows. First, the adhesive composition solution is prepared. Next, the adhesive composition solution is applied on the base separator so as to have a predetermined thickness to form a coating film, and then 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 adhesive sheet which concerns on this embodiment is obtained.

(Method for manufacturing semiconductor device)
Next, an embodiment of a method for manufacturing a semiconductor device will be described. Below, the manufacturing method of the semiconductor device using the dicing film integrated adhesive sheet 10 by which the adhesive sheet 3 which concerns on this embodiment was laminated | stacked on the conventionally well-known dicing film 11 is demonstrated. As a method for laminating the adhesive sheet 3 to the dicing film 11, a conventionally known method can be adopted, and for example, it can be performed by pressure bonding. The dicing film 11 according to this embodiment has a structure in which the pressure-sensitive adhesive layer 2 is laminated on the base material 1. 2 to 4 are schematic cross-sectional views for explaining the method for manufacturing a semiconductor device according to this embodiment.

  First, as shown in FIG. 2, the semiconductor wafer 4 is pressure-bonded onto the semiconductor wafer attaching portion 3a of the adhesive sheet 3 in the dicing film integrated adhesive sheet 10, and this is adhered and held and fixed (mounting step). . This step is performed while pressing with a pressing means such as a pressure roll.

  Next, dicing of the semiconductor wafer 4 is performed. Thereby, the semiconductor wafer 4 is cut into a predetermined size and separated into individual pieces, and the semiconductor chip 5 is manufactured. Dicing is performed according to a conventional method from the circuit surface side of the semiconductor wafer 4, for example. Further, in this step, for example, a cutting method called full cut for cutting up to the dicing film integrated adhesive sheet 10 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 is bonded and fixed by the dicing film integrated adhesive sheet 10, chip chipping and chip jump can be suppressed, and damage to the semiconductor wafer 4 can be suppressed.

  Next, the semiconductor chip 5 is picked up in order to peel off the semiconductor chip adhered and fixed to the dicing film integrated adhesive sheet 10. The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, a method of pushing up the individual semiconductor chips 5 from the dicing film integrated adhesive sheet 10 side with a needle and picking up the pushed-up semiconductor chips 5 with a pickup device or the like can be mentioned.

  Here, when the pressure-sensitive adhesive layer 2 is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 2 is irradiated with ultraviolet rays. Thereby, the adhesive force with respect to the adhesive sheet 3 of the adhesive layer 2 falls, and peeling of the semiconductor chip 5 becomes easy. As a result, the semiconductor chip 5 with the adhesive sheet 3 can be picked up without damaging the semiconductor chip.

  On the other hand, as shown in FIG. 3, a member 30 in which the semiconductor chip 16 is die-bonded on the adherend 6 via the die-bonding film 13 is prepared. The tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 16 are electrically connected (wire bonded) by a bonding wire 7. As the die bond film 13, a conventionally known film can be used. Examples of the adherend 6 include a lead frame, a TAB film, a substrate, and a separately manufactured semiconductor chip. The adherend 6 may be, for example, a deformable adherend that can be easily deformed or a non-deformable adherend (such as a semiconductor wafer) that is difficult to deform. The member 30 shown in FIG. 3 can be manufactured by a conventionally known method. For example, the die bonding is performed by pressure bonding. The conditions for die bonding are not particularly limited, and can be set as necessary. Specifically, for example, it can be performed within a die bonding temperature of 80 to 160 ° C., a bonding pressure of 5 N to 15 N, and a bonding time of 1 to 10 seconds. Moreover, the temperature at the time of performing the said wire bonding is 80-250 degreeC, Preferably it is performed within the range of 80-220 degreeC. 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.

  Next, as shown in FIG. 4, the semiconductor chip 5 with the adhesive sheet 3 is laminated on the upper surface of the semiconductor chip 16 so that a part of the bonding wire 7 is embedded in the adhesive sheet 3. Thereby, the connection part with the other semiconductor chip 16 of the bonding wire 7 is embedded in the adhesive sheet 3. As temperature at the time of this lamination | stacking, 80-200 degreeC is preferable and 100-150 degreeC is more preferable. In addition, the pressure at this time can be 0.05 MPa to 0.3 MPa, and the time can be 0.1 to 3 seconds. By setting the temperature at the time of lamination within the above range, the viscosity of the adhesive sheet 3 can be set to a viscosity at which the bonding wire 7 can be suitably embedded.

  Next, a wire bonding step is performed in which the tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 5 are electrically connected by the bonding wire 7 (see FIG. 1). 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.

  Next, a sealing step for sealing the semiconductor chip 5 and the semiconductor chip 16 with the sealing resin 8 is performed (see FIG. 1). This step is performed to protect the semiconductor chip 5, the semiconductor chip 16, and the bonding wire 7 mounted on the adherend 6. This step is performed by molding a sealing resin with a mold. As the sealing resin 8, for example, an epoxy resin is used. Although the heating temperature at the time of resin sealing is normally performed at 175 degreeC for 60 to 90 second, this invention is not limited to this, For example, it can cure at 165 to 185 degreeC for several minutes.

  Next, in the post-curing step, the sealing resin 8 that is insufficiently cured in the sealing step is completely cured. Even when the die bond film 13 and the adhesive sheet 3 are not thermally cured in the sealing process, the die bond film 13 and the adhesive sheet 3 are thermally cured together with the curing of the sealing resin 8 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 to 8 hours.

  In the embodiment described above, the case where the adhesive sheet 3 is laminated on the dicing film 11 has been described. However, a semiconductor in which a bonding wire is connected to the upper surface without being an adhesive sheet for manufacturing a dicing film integrated semiconductor device. The adhesive sheet may be directly attached to the chip so that a part of the bonding wire is embedded in the adhesive sheet.

  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
The following (a) to (g) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 50% by weight.
(A) Acrylic resin (manufactured by Nagase ChemteX Corporation, SG-700AS) 100 parts (b) Epoxy resin 1 (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S) 63.9 parts (c) Epoxy resin 2 (Mitsubishi Chemical Corporation, YL-983U) 12.3 parts (d) Phenolic resin (Maywa Kasei Co., Ltd., MEH-7851SS) 73.7 parts (e) Silica filler (manufactured by Admatechs) , SE2050-MCV (average primary particle size 0.5 μm) 138.89 parts (f) Ion scavenger (manufactured by Tokyo Chemical Industry Co., Ltd., dodecyl gallate) 27.78 parts (g) curing catalyst (Hokuko Chemical ( Co., Ltd., TPP-K) 0.5 part

  The adhesive composition solution was applied on a release treatment film made of a polyethylene terephthalate film having a thickness of 50 μm after the silicone release treatment, and then dried at 130 ° C. for 2 minutes. As a result, an adhesive sheet according to Example 1 having a thickness of 30 μm was produced.

(Example 2)
The following (a) to (g) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 50% by weight.
(A) acrylic resin (manufactured by Nagase ChemteX Corporation, SG-700AS) 100 parts (b) epoxy resin 1 (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S) 156.6 parts (c) epoxy resin 2 (Mitsubishi Chemical Corporation, YL-983U) 121.0 parts (d) Phenolic resin (Maywa Kasei Co., Ltd., MEH-7851SS) 289.0 parts (e) Silver filler (Mitsui Metals Co., Ltd.) , SPQ03S (average primary particle size 0.5 μm)
370.37 parts (f) ion scavenger (Johoku Chemical Co., Ltd., BT-120, benzotriazole)
74.07 parts (g) curing catalyst (manufactured by Hokuko Chemical Co., Ltd., TPP-K) 1.3 parts

(Example 3)
The following (a) to (g) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 50% by weight.
(A) Acrylic resin (manufactured by Nagase ChemteX Corporation, SG-700AS) 100 parts (b) Epoxy resin 1 (Nippon Kayaku Co., Ltd., EOCN-104S) 98.3 parts (c) Epoxy resin 2 (Mitsubishi Chemical Corporation, YL-983U) 50.6 parts (d) Phenolic resin (Maywa Kasei Co., Ltd., MEH-7851SS) 151.1 parts (e) Silica filler (manufactured by Admatechs) SE2050-MCV (average primary particle size 0.5 μm) 222.22 parts (f) ion scavenger (manufactured by Toa Gosei Co., Ltd., IXE-770) 44.44 parts (g) curing catalyst (Hokuko Chemical Co., Ltd.) ) Manufactured by TPP-K) 0.8 parts

(Comparative Example 1)
The following (a) to (f) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 50% by weight.
(A) acrylic resin (manufactured by Nagase ChemteX Corporation, SG-700AS) 100 parts (b) epoxy resin 1 (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S) 78.4 parts (c) epoxy resin 2 (Mitsubishi Chemical Corporation, YL-983U) 90.8 parts (d) Phenolic resin (Maywa Kasei Co., Ltd., MEH-7851SS) 180.8 parts (e) Silver filler (Mitsui Metal Co., Ltd.) , SPQ03S (average primary particle size 0.5 μm)
300.00 parts (f) Curing catalyst (manufactured by Hokuko Chemical Co., Ltd., TPP-K) 0.9 parts

(Comparative Example 2)
The following (a) to (f) were dissolved in methyl ethyl ketone to obtain an adhesive composition solution having a concentration of 50% by weight.
(A) acrylic resin (manufactured by Nagase ChemteX Corporation, SG-700AS) 100 parts (b) epoxy resin 1 (manufactured by Nippon Kayaku Co., Ltd., EOCN-1020) 139.1 parts (c) epoxy resin 2 (Mitsubishi Chemical Corporation, YL6810) 119.7 parts (d) Phenolic resin (Maywa Kasei Co., Ltd., MEH-7851SS) 204.3 parts (e) Silica filler (manufactured by Admatechs, SE2050) -MCV (average primary particle size 0.5 μm) 375.4 parts (f) Curing catalyst (manufactured by Hokuko Chemical Co., Ltd., TPP-K) 1.1 parts

(Measurement of melt viscosity at 140 ° C before thermosetting)
Using a rheometer (manufactured by HAAKE, trade name: RS-1), the melt viscosity at 140 ° C. before thermosetting was measured by a parallel plate method. Specifically, 0.1 g of an adhesive sheet was placed on a plate heated to 120 ° C., and measurement was started. The average value after 240 seconds from the start of measurement was taken as the melt viscosity. The gap between the plates was 0.1 mm. The results are shown in Table 1.

(Silver ion scavenging evaluation)
The adhesive sheets (thickness 30 μm) of Examples and Comparative Examples were cut into 240 mm × 300 mm sizes (about 2.5 g), respectively, and folded in half to a size of 37.5 mm × 60 mm. Into a cylindrical sealed Teflon (registered trademark) container having a diameter of 58 mm and a height of 37 mm, 50 ml of 10 ppm aqueous silver ion 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 film, the concentration of silver ions in the aqueous solution was measured using ICP-AES (manufactured by SII Nanotechnology, Inc., SPS-1700HVR). The case where the density | concentration of the silver ion in aqueous solution is 0-9.9 ppm was set as (circle), and the case where it is larger than 9.9 ppm was set as x. The results are shown in Table 1.

(Evaluation of chloride ion scavenging properties)
The adhesive sheets (thickness 30 μm) of Examples and Comparative Examples were cut into 240 mm × 300 mm sizes (about 2.5 g), respectively, and folded in half to a size of 37.5 mm × 60 mm. Into a cylindrical sealed Teflon (registered trademark) container having a diameter of 58 mm and a height of 37 mm, 50 ml of ion-exchanged water 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 removing the film, the concentration of chloride ions in the aqueous solution was measured using ion chromatography (product name ICS-2000, manufactured by Tokyo Dionex). The case where the concentration of the chloride ion in the aqueous solution was 0.1 ppm or less was rated as ◯, and the case where it was larger than 0.1 ppm was rated as x. The results are shown in Table 1.

(Moisture reflow resistance)
The adhesive sheets (thickness 30 μm) of Examples and Comparative Examples were respectively 60 ° C., 0.4 MP,
Bonding was performed at 50 cm / s to prepare an adhesive sheet having a thickness of 60 μm. Next, the prepared adhesive sheet (thickness 60 um) is bonded to a 10 mm square aluminum-deposited semiconductor chip at a temperature of 50 ° C., and the semiconductor chip is die-attached to the BGA substrate via each adhesive sheet. did. The die attach conditions were a temperature of 120 ° C., a pressure of 0.2 MPa, and 1 second. Next, wire bonding was performed using a 115 KHz wire bonder (manufactured by Shinkawa: UTC-300BIsuper) with a silver wire having a diameter of 25 μm (manufactured by Tanaka Kikinzoku, SEA) under the following conditions.
<Wire bonding conditions>
First bonding pressure: 100g
First bonding ultrasonic intensity: 550mW
First bonding application time: 10 msec
Second bonding pressure: 100g
Second bonding ultrasonic intensity: 500mW
Second bonding application time: 8 msec
Next, the semiconductor chip is die-attached on the semiconductor chip subjected to wire bonding under the same conditions as described above, and stacked while performing wire embedding.
Next, it heat-processed at 130 degreeC with the dryer for 2 hours, and packaged with sealing resin (Nitto Denko Co., Ltd. make, GE-100) after that. The sealing conditions were a heating temperature of 175 ° C. and 90 seconds. Thereafter, the BGA substrate mounted with the semiconductor chip was placed in an IR reflow furnace set so as to absorb moisture under conditions of 85 ° C., 60% Rh and 168 hours, and further hold at 260 ° C. or higher for 10 seconds. Thereafter, the sealed semiconductor device was observed with an ultrasonic microscope to confirm the presence or absence of peeling. Confirmation was performed on nine semiconductor chips, and when the number of peeled semiconductor chips was 2 or less, ◯, and when two or more semiconductor chips were marked as x. The results are shown in Table 1 below.

(Evaluation of wire embedment)
The adhesive sheets (thickness: 60 μm) of Examples and Comparative Examples were attached to the first semiconductor element (5 × 5 × 0.5 mm) with a laminator at 50 ° C., 10 mm / sec, and pressure of 0.15 MPa. I attached. Next, a second semiconductor element (5 × 5 × 0.5 mm, wire loop height: 40 μm) which was die-attached on the substrate and connected with bonding wires was prepared. Next, the first semiconductor element with an adhesive sheet is heated to 140 ° C., pressure 0.1 MPa, time using a die bonder (SPIN300 SPA300) on the surface of the second semiconductor element to which the bonding wires are connected. Affixed vertically under the condition of 1 sec. The pasting was performed so that the adhesive sheet surface of the first semiconductor element with the adhesive sheet and the surface of the second semiconductor element on the side to which the bonding wire was connected were opposed to each other. Then, it was confirmed using the scanning electron microscope (HITACHI S-3400N) whether the bonding wire of the 2nd semiconductor element was embedded in the adhesive sheet without generating a void. The case where no void was found was evaluated as ◯, and the case where a void was seen was evaluated as x. The results are shown in Table 1.

(HAST resistance evaluation)
The resistance to HAST (High Accelerated Stress Test) was confirmed by the following method. First, as shown in FIG. 5, a substrate 21 in which a copper comb electrode pattern 15 was provided on the surface of a polyimide substrate 14 was prepared. The comb-shaped electrode pattern 15 includes a plus electrode 15a and a minus electrode 15b, and is formed so that the line width / space width is 20 μm / 20 μm. Next, a semiconductor chip to which the adhesive sheets of Examples and Comparative Examples were attached was prepared. The surface of the semiconductor chip on which the adhesive sheet was affixed was laminated on the comb-shaped electrode pattern 15 of the substrate 21 under the conditions of 120 ° C., 0.2 MPa, 10 mm / sec seconds to obtain a sample. Thereafter, the obtained sample was cured in a pressure oven at 150 ° C. for 1 hour in a nitrogen atmosphere at a pressure of 5N. Thereafter, the adhesive sheet layer was cured by heating at 175 ° C. for 5 hours. The positive electrode and negative electrode of the obtained sample were each connected to the wiring of the HAST test with solder, and the test was performed under the conditions of 50 ° C., 85% RH, and 5V. The electrical resistance is monitored, and those that can be maintained without declining rapidly even after 196 hours are regarded as non-defective products, and those that cause a rapid decrease in electrical resistance are regarded as defective products (electrical fault occurrence). . Five samples were prepared and tested in the same manner. When the number of defective samples was 2 or less, ◯, and when more than 2, the sample was rated as x. The results are shown in Table 1.

Claims (4)

A semiconductor device having an adhesive layer and a bonding wire,
A portion of the bonding wire is embedded in the adhesive layer;
The adhesive sheet used for the adhesive layer is immersed in 50 ml of an aqueous solution containing 10 ppm of silver ions in the aqueous solution after immersing the adhesive sheet of 2.5 g in weight before thermosetting and leaving it at 120 ° C. for 20 hours. silver ion concentration of, Ri 0~9.9ppm der,
The adhesive sheet used in the adhesive layer, a semiconductor device which is characterized that you containing ion scavenger for capturing at least a cation. The adhesive sheet used for the adhesive layer is a chloride ion in the aqueous solution after immersing the adhesive sheet before thermosetting weighing 2.5 g in 50 ml of ion exchange water and leaving it at 120 ° C. for 20 hours. The semiconductor device according to claim 1, wherein the concentration is 0.1 ppm or less. The ion scavenger, a semiconductor device according to claim 1 or 2, characterized in that an organic complex forming compound to form a cationic complexes. 4. The semiconductor device according to claim 3 , wherein the organic complex-forming compound is at least one selected from the group consisting of a nitrogen-containing compound, a hydroxyl group-containing compound, and a carboxylic acid group-containing compound.

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