JP2003347321A - Die-attach film, manufacturing method of semiconductor device employing it and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a die-attach film which also functions as a dicing film and is bonded to a wafer at a normal temperature or under a mild condition in an assembling process for a semiconductor. <P>SOLUTION: The die-attach film with a dicing sheet function is constituted of a thermoplastic polyimide resin having a glass transition temperature of 90°C or higher, an adhesive for die-bonding made of a thermo-setting resin and a light transmitting substrate while the film can be bonded to the rear surface of the wafer on which a plurality of semiconductor elements are formed at low temperatures of less than 50°C. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a die attach film, a method for manufacturing a semiconductor device using the same, and a semiconductor device. More specifically, the present invention relates to a die attach film for processing a semiconductor wafer made of silicon, gallium, arsenic, or the like used for processing a wafer, a method of manufacturing a semiconductor device using the same, and a semiconductor device.

[0002]

2. Description of the Related Art In recent years, demands for higher density and higher integration of semiconductor devices have increased in response to the recent increase in the functionality of electronic devices and the expansion to mobile applications, and the increase in the capacity and density of IC packages has been progressing. . As a method for manufacturing these semiconductor devices, an adhesive sheet is attached to a semiconductor wafer made of silicon, gallium, arsenic, etc., cut and separated into individual semiconductor elements by dicing, expanding, picking up individual chips, Next, the semiconductor chip is transferred to a semiconductor device assembling process in which the semiconductor chip is die-bonded to a metal lead frame, a tape substrate, or an organic hard substrate.

[0003] In a die bonding step, the picked-up semiconductor chip is bonded to a lead frame or a substrate via a die attach material such as a liquid epoxy adhesive to manufacture a semiconductor device. However, when the chip is small such as for mobile use, it is difficult to apply an appropriate amount of adhesive, and when the adhesive protrudes from the chip or a large chip for large-capacity applications,
On the contrary, there is a problem that it is not possible to have a sufficient adhesive force such as a shortage of the adhesive. Further, the application step of the adhesive is complicated, and improvement is required to simplify the process.

[0004] In order to solve this problem, it has been proposed to use a film adhesive as a die attach material instead of a liquid die attach material. In some cases, a film adhesive has been used. Heating is required when the wafer is attached to the wafer, and a problem arises in that the wafer is warped or cracked when the die attach material is attached as the wafer becomes thinner. For this reason, in order to attach the resin at a low temperature, a thermoplastic resin having a low glass temperature has been used. However, when the glass transition temperature is low, reflow resistance may be reduced.

As a method for solving such a problem, a viscous adhesive sheet for attaching a wafer having both a wafer fixing function at the time of processing a semiconductor wafer and a die attach function at a die bonding step is used, and a glass transition temperature of 90 ° C. or more. Using thermoplastic polyimide resin and thermosetting resin,
Using the existing dicing film infrastructure, a composite film of a dicing film and a die attach film is bonded to the wafer at room temperature or mild conditions, and after dicing, only the base material is peeled off to obtain a die attach film with excellent reflow resistance. It is to try.

[0006]

SUMMARY OF THE INVENTION According to the present invention, in order to improve / improve the prior art as described above, a film having both functions of a die attach film and a dicing film is attached to a wafer at normal temperature or mild conditions. This is a technology to provide a die attach film that can be used as a dicing sheet with excellent chipping resistance and crack characteristics, can be used as an adhesive at the time of die mounting, and has a uniform thickness ,
It is an object of the present invention to provide a die attach film having excellent adhesive strength and shear strength characteristics, and having excellent reflow resistance to withstand severe wet heat conditions, a method for manufacturing a semiconductor device using the same, and a semiconductor device.

[0007]

SUMMARY OF THE INVENTION The present invention provides (1) a die bonding adhesive containing a thermoplastic polyimide resin having a glass transition temperature of 90 ° C. or higher, and a thermosetting resin; A) a die attach film having a dicing sheet function, comprising a die bonding adhesive according to the above item and a light-transmitting substrate, which can be attached at a low temperature of 50 ° C. or less to the back surface of a wafer on which a large number of semiconductor elements are formed; 3) (A) a step of bonding the back surface of the silicon wafer with the die attach film having a dicing sheet function according to the item (2) at a temperature of 50 ° C. or lower, and (B) a step of dicing the silicon wafer and cutting it into individual dies.
(C) a step of irradiating the surface of the die attach film with ultraviolet light after dicing to cure the contact interface of the adhesive layer with the light-transmitting substrate, and (D) curing the adhesive layer with ultraviolet light and then backside (E) a step of heating and bonding the die to a lead frame or a substrate through a die attach film. A semiconductor device and a lead frame or a substrate are bonded by the method for manufacturing a semiconductor device according to (4), the die bonding adhesive described in (1), or the die attach film having a dicing sheet function described in (2). Semiconductor device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is a die attach film having a dicing function comprising a pressure-sensitive adhesive layer and a light-transmitting base material.
It is characterized in that the wafer is attached at the following low temperature.

The thickness of the light-transmitting substrate used in the present invention is preferably from 20 to 200 μm, and particularly preferably from 25 to 150 μm.

The light-transmitting substrate used in the present invention includes a polypropylene film, a polyethylene film, a polybutadiene film, a polyvinyl chloride film, etc., and 30 to 70 parts by weight, preferably 40 to 60 parts by weight of polypropylene. It is preferably a mixture of a resin and 70 to 30 parts by weight, preferably 60 to 40 parts by weight, of a copolymer composed of a polystyrene block and a vinyl isoprene block.

In the present invention, the adhesive used for the adhesive layer has a sufficient adhesive property when not cured, and contains a component which is cured by irradiating ultraviolet rays of 370 nm or less,
It is preferable that the adhesive layer has a feature that it has no tackiness at the interface between the adhesive layer hardened by ultraviolet irradiation and the adherend.

The adhesive layer preferably has an absorptivity for ultraviolet light of 370 nm or less of 60% or more, and curing proceeds only on the surface irradiated with ultraviolet light. The absorption is more preferably 7
0% or more, more preferably 80% or more.

The adhesive used in the present invention preferably contains a resin having an imide ring. By having an imide ring, the absorption of ultraviolet light is further promoted, and the absorptivity of ultraviolet light is more than the above value. And light is absorbed by the ultraviolet light irradiation surface.

The adhesive preferably further contains an ultraviolet-curable adhesive component and a thermosetting adhesive component.

Examples of the resin having an imide ring used in the present invention include a polyimide resin, a polyamide imide resin, a polyether imide resin, and a polyether ether imide resin. Among them, a polyimide resin is preferable.

Further, as the polyimide resin, a general formula (A) obtained by reacting an aromatic tetracarboxylic dianhydride, a diaminopolysiloxane represented by the general formula (1), and an aromatic or aliphatic diamine is used. The polyimide resin represented by 2) is more preferable.

[0017]

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[0018]

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(In the formulas (1) and (2), R ₁ and R ₂ represent a divalent aliphatic or aromatic group having 1 to 4 carbon atoms;
R ₃ , R ₄ , R ₅ and R ₆ are monovalent aliphatic or aromatic groups; R ₇ and R ₈ are tetravalent aliphatic or aromatic groups;
₉ represents a divalent aliphatic or aromatic group, and m: n is 5
-80: 95-20. k is an integer of 1 to 50, and the same integer is used in both the formulas (1) and (2). )

The diaminopolysiloxane is preferably a diaminopolysiloxane having 1 to 9 and / or 10 to 50 repeating units as k in the general formula (1).

The aromatic tetracarboxylic dianhydride used in the present invention includes 3,3,4,4'-biphenyltetracarboxylic dianhydride and 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride. Anhydride, pyromellitic dianhydride, 4,4'-oxydiphthalic dianhydride, ethylene glycol bistritometic dianhydride, 4,4 '-(4,
4'-isopropylidenediphenoxy) phthalic dianhydride and the like. The above aromatic tetracarboxylic dianhydrides may be used alone or in combination of two or more.

The diaminopolysiloxane represented by the general formula (1) used in the present invention includes 1,3-bis (3-aminopropyl) tetramethylsiloxane and α, ω-bis (3-aminopropyl) polydimethyl Siloxane and the like. Among them, in the general formula (1), k is 1 to 9
And / or 10 to 50. Adhesion is improved by using 1 to 9, and fluidity is improved by using 10 to 50, and can be selected according to the purpose. It is more preferable to use both together.

The aromatic or aliphatic diamine used in the present invention includes 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,6-dimethyl-m-phenylenediamine, and 2,5-dimethyl-p-diamine. Phenylenediamine,
2,4-diaminomesitylene, 4,4'-methylenedi-
o-Toluidine, 4,4'-methylenediamine-2,6
-Xylidine, 4,4'-methylene-2,6-diethylaniline, 2,4-toluenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylpropane, 3,3'-diaminodiphenyl Propane, 4,4'-diaminodiphenylethane, 3,
3'-diaminodiphenylethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 3,
3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, benzidine, 3 , 3′-Diaminobiphenyl, 3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxybenzidine, bis (p-aminocyclohexyl) methane, bis (p-β-amino-t-butyl) Phenyl) ether, bis (p-β-methyl-δ-aminopentyl)
Benzene, p-bis (2-methyl-4-aminopentyl) benzene, 1,5-diaminonaphthalene, 2,6-
Diaminonaphthalene, 2,4-bis (β-amino-t-
Butyl) toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine, p-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-diamino-1,3,4-oxadiazol, 1,4-diaminocyclohexane, piperazine,
Methylenediamine, ethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, 3
-Methoxyhexamethylenediamine, heptamethylenediamine, 2,5-dimethylheptamethylenediamine, 3
-Methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine, octamethylenediamine, nonamethylenediamine, 5-methylnonamethylenediamine,
Decamethylenediamine, 1,3-bis (3-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,3-bis (4-aminophenoxy) benzene, bis- 4- (4-aminophenoxy) phenylsulfone, bis-4- (3-aminophenoxy) phenylsulfone and the like can be mentioned. The above diamines may be used alone or in combination of two or more.

Usually, the solvent used when synthesizing a polyimide resin is a solvent having a very high boiling point, such as N-methylpyrrolidone. is there. However, by using a low boiling point solvent such as anisole as a solvent for the polyimide resin used in the present invention, the drying temperature during film processing can be set low.

In the present invention, a silicone-modified polyimide resin such as the polyimide resin represented by the general formula (2) is more preferable, but it is more preferable that it is soluble in a low boiling point solvent such as anisole. As the ratio of silicone modification, from the solubility in solvents and film properties,
The ratio of m and n in the general formula (2) is 5 to 80:95.
-20 is preferred.

The UV-curable adhesive component used in the present invention is preferably an acrylic compound (A-1), and examples thereof include acrylic acid or methacrylic acid ester monomers and copolymers of acrylic acid or methacrylic acid derivatives. . As acrylic acid or methacrylic acid ester, for example, alkyl esters such as methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, benzyl ester, cycloalkyl ester, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diacrylic acid 1,6-hexanediol, 1,6-hexanediol dimethacrylate,
Glycerin diacrylate, glycerin dimethacrylate,
Bifunctional acrylates such as 1,10-decanediol diacrylate and 1,10-decanediol dimethacrylate;
Examples include polyfunctional acrylates such as trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexaacrylate, and dipentaerythritol hexamethacrylate. Of these, alkyl esters are preferred, and particularly preferred are those having 1 to 1 carbon atoms in the ester moiety.
5 acrylic acid and methacrylic acid alkyl ester.

The molecular weight of the acrylic compound (A-1) other than the monomer used in the present invention is preferably 80,000 or more, and particularly preferably 150,000 to 500,000. The glass transition temperature of the acrylic compound is usually 30 ° C. or lower, preferably about −50 ° C. to 0 ° C., and a compound exhibiting tackiness in a temperature range near room temperature is preferred.

As the copolymer having a constitutional unit of an acrylic acid or methacrylic acid derivative used in the present invention, a copolymer of at least one alkyl ester of acrylic acid or methacrylic acid and a bisphenol A type (meth) acrylic acid ester is used. Coalescence is preferred. Further, a combination of a bifunctional di (meth) acrylate and glycidyl (meth) acrylate is also preferable.

The content of the component units derived from acrylic acid or methacrylic acid ester is usually 20 to 55 mol%, preferably 30 to 40 mol%, based on 100 parts by weight of the resin having an imide ring. Examples of the acrylic acid and alkyl methacrylate include methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, and the like. If it is less than 20 mol%, the adhesive strength is poor, and if it exceeds 55 mol%, the adhesion to the protective film becomes more than necessary.

Further, by introducing an acrylic or methacrylic ester of a UV-curable resin having a hydroxyl group such as a hydroxy group in the molecule, the adhesion to the adherend and the properties of the adhesive can be easily controlled. be able to.

By further mixing the photopolymerization initiator (A-2) with the ultraviolet-curable adhesive component, the curing time and the amount of light irradiation during ultraviolet irradiation can be reduced. It is also an important component for peeling off from the substrate and using it as a die attach film.

Examples of the photopolymerization initiator (A-2) include benzophenone, acetophenone, benzoin, benzoin isobutyl ether, methyl benzoin benzoate, benzoin benzoic acid, benzoin methyl ether, benzyl finyl sulfide, Benzyl,
Dibenzyl, diacetyl and the like.

The ultraviolet-curable pressure-sensitive adhesive component used in the present invention preferably comprises the above components (A-1) to (A-2), and the compounding ratio thereof is appropriately set according to the characteristics of each component. However, generally, the component (A-2) is preferably 3 to 30 parts by weight with respect to 100 parts by weight of the component (A-1),
More preferably, it is used in an amount of about 5 to 15 parts by weight. If the amount is less than 3 parts by weight, the effect of the photoinitiator is weak, and
Exceeding parts by weight increases reactivity and deteriorates storage stability.

The thermosetting adhesive component used in the present invention is not cured by irradiation with ultraviolet rays, but the thermosetting reaction proceeds by heating to form a three-dimensional network, and a metal lead frame and a tape or an organic hard substrate to be adhered. Is firmly adhered.

As such a thermosetting adhesive component, generally, epoxy resin, phenol resin, urea resin,
It is formed from a thermosetting resin such as a melamine resin and a suitable curing accelerator for each. Various such thermosetting adhesive components are known, and in the present invention, various known thermosetting adhesive components can be used without particular limitation. As such an adhesive component, for example, a resin composition of an epoxy resin (B-1) and a heat-active latent epoxy resin curing agent (B-2) can be mentioned.

As the epoxy resin (B-1), various well-known epoxy resins can be used.
A resin having a molecular weight of about 300 to 800 is particularly preferable, and a normal temperature liquid epoxy resin having a molecular weight of 300 to 800 and a molecular weight of 400 to 2000, preferably 500 to 15 are preferable.
It is desirable to use the resin in the form of a blend with a room temperature solid epoxy resin. The epoxy equivalent of the epoxy resin particularly preferably used in the present invention is usually 50 to 8
000 g / eq.

Specific examples of such an epoxy resin include bisphenol A epoxy resins, bisphenol F epoxy resins such as bisphenol F epoxy resins, phenol novolak epoxy resins, cresol novolak epoxy resins, and polyethylene glycol epoxy resins. Resins and the like can be mentioned. These are 1
Species can be used alone or in combination of two or more. Among them, bisphenol type epoxy resin, cresol novolak type epoxy resin and phenol novolak type epoxy resin are particularly preferable.

In the present invention, the heat-active latent epoxy resin curing agent (B-2) is a type of curing agent that does not react with the epoxy resin at room temperature but is activated by heating at a certain temperature or higher and reacts with the epoxy resin. Agent.

Thermally active latent epoxy resin curing agent (B-
The activation method of 2) includes a method of generating an active species (anion or cation) by a chemical reaction by heating, a method of dissolving and dissolving with an epoxy resin at around room temperature to start a curing reaction, and a method of enclosing a molecular sieve. There are a method of initiating a curing reaction by eluting at a high temperature with a type of curing agent, and a method using microcapsules.

As the heat-active latent epoxy resin curing agent, dicyandiamide, imidazole compounds and mixtures thereof are preferable, and an adduct of 2-methylimidazole and isocyanate may be used. These may be used alone or in combination of two or more.

In the thermosetting adhesive component used in the present invention, the heat-active latent epoxy resin curing agent (B-
2) is usually preferably 1 to 20 parts by weight, particularly preferably 5 to 15 parts by weight, based on 100 parts by weight of the epoxy resin (B-1). When the amount is less than 1 part by weight, the effect of the resin curing agent is small, and when the amount exceeds 20 parts by weight, the reactivity is increased and the storage stability is deteriorated.

The adhesive layer of the present invention may contain a filler, and the filler has an average particle size of 0.1 to 25 μm.
m is preferable. When the average particle size is less than 0.1 μm, the effect of adding a filler is small, and when the average particle size exceeds 25 μm, the adhesive strength as a film may be reduced.

As the filler used in the adhesive layer of the present invention, silver, titanium oxide, silica, mica and the like are preferable.

The content of the filler is preferably 0% to 30% by weight, and if it exceeds 30%, the film becomes brittle and the adhesiveness is reduced.

The adhesive used in the present invention preferably contains 20 to 80 parts by weight, more preferably 30 to 80 parts by weight of an ultraviolet-curable adhesive component based on 100 parts by weight of the resin having an imide ring.
60 parts by weight, and the thermosetting adhesive component is preferably 20 parts by weight.
When added in an amount of from 80 to 80 parts by weight, particularly preferably from 30 to 50 parts by weight, adhesiveness, adhesiveness and heat resistance can be exhibited.

The method for producing a die attach film having a dicing sheet function according to the present invention is as follows. First, a pressure-sensitive adhesive resin composition comprising the above components is coated in a varnish form on a release sheet, using a comma coater, a die coater, or a gravure coater. In accordance with a generally known method, such as coating and drying, an adhesive layer is formed. Thereafter, the release sheet is removed to form a pressure-sensitive adhesive film, which is laminated on a light-transmitting substrate, and a protective film is further laminated on the adhesive film to form a protective film, a pressure-sensitive adhesive layer, and a light-transmitting layer. A die attach film having a dicing sheet function comprising a base material can be obtained. Alternatively, a dicing sheet comprising a protective film (release sheet), an adhesive layer, and a light-transmitting substrate, which is laminated on a light-transmitting substrate on the adhesive layer formed on the release sheet. A die attach film with a function can be obtained.

Alternatively, a pressure-sensitive adhesive composition is applied directly on a light-transmitting substrate in the same manner as described above, dried, and a protective film is laminated on the adhesive film to form a protective film and a pressure-sensitive adhesive. Layer and a die attach film having a dicing sheet function, comprising a light-transmitting substrate.

The thickness of the adhesive layer thus formed is preferably 3 to 100 μm, more preferably 10 to 75 μm. When the thickness is less than 3 μm, the effect as a pressure-sensitive adhesive is reduced, and when it exceeds 100 μm, it is difficult to produce a product, and the thickness accuracy is deteriorated.

The method of manufacturing a semiconductor device according to the present invention comprises:
After attaching the adhesive layer of the die attach film with the dicing sheet function of the present invention to the back surface of the silicon wafer at room temperature or under mild conditions, the silicon wafer with the die attach film is diced using the die attach film as the dicing film. The above-mentioned silicon wafer with a die-attach film is cut into individual pieces by using a cutting means such as a dicing saw, and semiconductor chips are formed into individual dies.

Subsequently, ultraviolet rays (center wavelength = approximately 365 nm) are applied to the light transmitting substrate surface of the die attach film attached to the semiconductor chip obtained as described above.
Usually, the illuminance is set in the range of ^{20 to} 500 mJ / cm ² , and the irradiation time is set in the range of 5 to 600 seconds. Various conditions can be set according to the above-described ultraviolet irradiation.

Next, only the light-transmitting substrate is peeled off while the die attach film remains fixed on the back surface of the semiconductor chip.

In this manner, the semiconductor chip to which the adhesive layer of the die attach film is adhered is directly heated and connected to a metal lead frame or a substrate via the adhesive layer.
By performing pressure bonding, die bonding can be performed.
The heating and pressure bonding conditions are usually a heating temperature of 100 to 300 ° C. and a pressure bonding time of 1 to 10 seconds, preferably 1 to 10 seconds.
Heating at 00 to 200 ° C. and pressure bonding time of 1 to 5 seconds. Subsequently, when the thermosetting adhesive component is included in the die attach film, by further heating as a post-treatment, the thermosetting adhesive component in the die attach film is cured,
A semiconductor device in which a semiconductor chip is firmly bonded to a lead frame, a substrate, or the like can be obtained. The heating temperature in this case is usually about 100 to 300 ° C., preferably 1 to 300 ° C.
The heating time is usually about 1 to 24.
0 minutes, preferably 10 to 60 minutes.

The finally cured die attach film has high heat resistance and a resin component having an imide ring which is not involved in thermosetting contained in the die attach film, for example, a cured polyimide resin having high heat resistance. The material has low brittleness, excellent shear strength and high impact resistance,
Has heat resistance.

[0054]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples.

(A) UV-curable adhesive component [(A-1) (meth) acrylate monomer]
1,6-hexanediol dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd.) [(A-2) Photopolymerization initiator] 2,2-dimethoxy key
1,2-diphenylethan-1-one (manufactured by Ciba-Geigy Corporation)

(B) Thermosetting adhesive component [(B-1) epoxy resin] (B-1-1) Cresol novolak epoxy resin (trade name: EOCN-1020-80, epoxy equivalent: 20)
0 g / eq, manufacturer: Nippon Kayaku Co., Ltd. [(B-2) Thermally active latent epoxy resin curing agent] (B-2-1) Imidazole compound (trade name: 1B2M)
Z, manufacturer: Shikoku Kasei)

(C) Resin component containing imide group (C-1) Silicone-modified polyimide resin,
As diamine components, 2,2-bis [4- (4-aminophenoxy) phenyl] propane (0.15 mol) and α, ω-bis (3-aminopropyl) polydimethylsiloxane (average molecular weight 837) (0. 15 mol) to obtain an anisole-soluble polyimide resin using 4,4'-oxydiphthalic dianhydride (0.30 mol) as an acid component. The molecular weight is Mw = 60000. (C-2) Silicone-modified polyimide resin,
As a diamine component, 2,2-bis [4- (4-aminophenoxy) phenyl] propane (0.15 mol) and α,
Based on ω-bis (3-aminopropyl) polydimethylsiloxane (average molecular weight: 837) (0.15 mol), 4,4′-oxydiphthalic dianhydride (0.15 mol) was used as an acid component.
Mol) 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride-soluble polyimide resin was obtained using anisole. The molecular weight is Mw = 50,000. (C-3) Silicone-modified polyimide resin,
1,3-bis (3-aminophenoxy) benzene (0.15 mol) and α, ω-bis (3-aminopropyl) polydimethylsiloxane (average molecular weight 8
37) With respect to (0.15 mol), a polyimide resin soluble in anisole using 4,4′-oxydiphthalic dianhydride (0.30 mol) as an acid component was obtained. The molecular weight is Mw =
60000.

(D) Filler (D-1) Silica filler SP-4B (average particle size 4 μm)
m) (Manufacturer: Fuso Chemical Co., Ltd.)

A 100 μm thick film of Cleartech CT-H817 (manufactured by Kuraray) comprising 60 parts by weight of a light-transmitting base material Hybra and 40 parts by weight of polypropylene was formed by an extruder.

Example 1 Each component was prepared at the ratio shown in Table 1 to obtain an adhesive composition. This adhesive composition was applied to a polyethylene terephthalate substrate of 100 μm and dried to obtain an adhesive film. By laminating a light-transmissive substrate on this adhesive film and laminating, a die attach film with a dicing sheet function comprising a protective film (polyethylene terephthalate substrate), an adhesive layer, and a light-transmissive substrate is formed. Produced. After peeling off the protective film of the die attach film, a semiconductor wafer is stuck on the surface of the adhesive layer, fixed and held, using a dicing saw, at a spindle rotation speed of 50,000 rpm, a cutting speed of 50 mm / sec, and a 5 × 5 mm square. Cut into chip sizes. Then, after irradiating the integrated light amount of 250 mJ / cm ² with ultraviolet rays for 20 seconds, the light-transmitting substrate is peeled off from the semiconductor chip remaining on the die attach film, and then the semiconductor chip is put through an adhesive layer. 42
-180 ℃ -1MPa on alloy alloy lead frame
Crimping was performed under the condition of -1.0 sec, die bonding was performed, and each item as a dicing sheet and a die attach film was evaluated. The results are shown in Tables 2 and 3.

Example 2 The same operation as in Example 1 was performed except that the mixing ratio of the adhesive component was changed as shown in Table 1.

Comparative Example 1 The mixing ratio of the adhesive component was
The same operation as in Example 1 was performed except for the change as shown in Table 1.

[0063]

[Table 1]

[0064]

[Table 2]

[0065]

[Table 3]

The following evaluation methods were used to evaluate the examples and comparative examples. (1) Adhesive layer peeling rate A die attach film with a dicing sheet function is attached to the back surface of the wafer at 25 ° C., and then irradiated with ultraviolet light after dicing.
The semiconductor device was mounted at -1 MPa-1s and molded with a sealing material manufactured by Sumitomo Bakelite Co., Ltd. The sealed sample was treated for 168 hours in a constant temperature / humidity chamber of 85 ° C./85% Rh, and then treated at 240 ° C. in an IR reflow furnace. Thereafter, the cross section was observed with a microscope to evaluate the peeling rate of the adhesive layer and the rate of occurrence of reflow cracks. (2) Scattering of chips after dicing After dicing the semiconductor wafer, evaluation was made by counting the number of semiconductor chips peeled off from the die attach film because of weak adhesion. (3) Chipping characteristics ：: Chip width is 30 μm or less at maximum. Δ: The width of the chip is 30 to 50 μm at the maximum. ×: The width of the chip is 50 μm or more at the maximum. (4) Pickup properties The semiconductor wafer was irradiated with ultraviolet light after dicing, and it was evaluated whether the semiconductor chip with the die attach film could be picked up from the light transmitting substrate (pickup). Good: Almost all the chips can be picked up. Δ: 50 to 90% of the diced chips can be picked up. X: Pickup is 50% or less. (5) With initial adhesive die attach film as die attach film A semiconductor chip is mounted on a 42-alloy lead frame at 180 ° C.-1 MPa-1.0 s.
Die bonding was performed under the condition of ec, and the shear strength between the chip and the lead frame was measured and evaluated in an untreated state. (6) Adhesion after moisture absorption The measurement sample die-bonded in (3) above was
C./85% RH / 168 hours after the moisture absorption treatment, the shear strength between the chip and the lead frame was measured and evaluated. ：: Shear strength of 1 MPa or more △: Shear strength of 0.5 to 1.0 ×: Shear strength of less than 0.5 (7) UV Absorbance The method of measuring UV absorptivity is as follows.
Ultraviolet light of nm to 375 nm was applied to the adhesive layer, and the absorbance was measured with an absorbance meter.

[0067]

According to the present invention, a wafer is stuck under mild conditions, has a function as a dicing sheet having excellent chipping resistance and cracking properties as a dicing film during dicing, and is used as an adhesive during die mounting. The use of a thermoplastic polyimide resin at 90 ° C. or higher can provide a die attach film that is excellent in uniformity of thickness, adhesive strength, and shear strength, and can withstand severe wet heat conditions. A semiconductor device using the same has impact resistance and heat resistance equal to or higher than that of a conventional liquid epoxy die attach material.

Claims (4)

[Claims] 1. An adhesive for die bonding, comprising a thermoplastic polyimide resin having a glass transition temperature of 90 ° C. or higher, and a thermosetting resin. 2. A dicing sheet function comprising the adhesive for die bonding according to claim 1 and a light-transmissive substrate, which can be stuck at a low temperature of 50 ° C. or less to the back surface of a wafer on which a large number of semiconductor elements are formed. With die attach film. And (A) a step of bonding the back surface of the silicon wafer with the die attach film having a dicing sheet function according to claim 2 at a temperature of 50 ° C. or less, (B) a step of dicing the silicon wafer and separating it into individual dies. (C)
A step of irradiating the surface of the die attach film with ultraviolet rays after dicing to cure the contact interface of the adhesive layer with the light-transmitting substrate, and (D) curing the adhesive layer with ultraviolet rays and then die-attaching the back surface. A pickup step of peeling and removing the die with the film left from the light-transmitting substrate, (E) the die,
A method of heating and bonding to a lead frame or a substrate via a die attach film. 4. A semiconductor device comprising a semiconductor element and a lead frame or a substrate bonded by the die bonding adhesive according to claim 1 or the die attach film having a dicing sheet function according to claim 2.