JP2009167372A - Adhesive for electrical part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive for electrical parts imparting a cured products with a proper flexibility at normal temperature and at a high temperature range after curing, excellent in adhesion of the electrical parts such as a semiconductor chip, etc., to a substrate, preventing generation of a large warpage on the electrical parts such as the semiconductor chip etc., adhered on the substrate. <P>SOLUTION: The adhesive for the electrical parts consists of (A) an epoxy compound having a 3-6C polyether skeleton, an aromatic skeleton and a glycidyl ether skeleton directly bonding to the aromatic skeleton, (B) an epoxy compound having a 3-6C aliphatic polyether skeleton and a glycidyl ether skeleton directly bonding to the aliphatic polyether skeleton, (C) a hardener, and (D) a polyfunctional epoxy having an aromatic skeleton and 50-150 of epoxy equivalents and/or an inorganic filler, wherein the adhesive has at least 4 MPa of storage elastic modulus at 260°C, after curing. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The cured product after curing has moderate flexibility at room temperature and high temperature range, and has excellent adhesion between an electrical component such as a semiconductor chip and a substrate, and is great for an electrical component such as a semiconductor chip adhered to a substrate. The present invention relates to an adhesive for electrical parts that can prevent warping.

In recent years, there is an increasing demand for miniaturization of electrical components such as semiconductor chips. For example, semiconductor chips are becoming thinner. Accordingly, when the semiconductor chip and the substrate are bonded via the adhesive, the problem of warpage occurring in the semiconductor chip has become an increasingly important issue.
The problem of warpage occurring in the semiconductor chip is that the elongation dependence between the semiconductor chip and the substrate during the process of cooling from the temperature at which the adhesive bonding the semiconductor chip and the substrate is cured to room temperature. It is considered that the stress caused by the difference is a major factor.

In order to solve such a problem, for example, it is considered that an adhesive that bonds between a semiconductor chip and a substrate is used to relieve a stress caused by a difference in temperature dependence of the elongation rate between the semiconductor chip and the substrate.
Here, in order to relieve the stress caused by the difference in temperature dependence of the elongation rate between the semiconductor chip and the substrate, the adhesive that bonds between the semiconductor chip and the substrate is the storage modulus of the cured product at room temperature. Is required to be 1 GPa or less (for example, see Patent Document 1). However, even when such an adhesive is used, when the semiconductor chip or the substrate is extremely thin, the generation of warping has not been sufficiently suppressed. In addition, a general polymer compound that satisfies this condition has a storage elastic modulus of less than 4 MPa at around 260 ° C., and the semiconductor chip and the substrate are bonded with an adhesive made of such a polymer compound. Then, there was a problem of reflow peeling.

On the other hand, as a method for keeping the storage elastic modulus at room temperature at 1 GPa or less and the storage elastic modulus at 260 ° C. exceeding 4 MPa, the acrylic resin and the epoxy compound are phase-separated, and further in these resins Discloses a method of highly filling a filler (for example, see Non-Patent Document 1). However, in addition to the problem that such an adhesive is inferior in adhesive strength, there is also a problem that it may be inferior in storage stability. In addition, when the semiconductor chip or the substrate is extremely thin, the occurrence of warpage may not be sufficiently suppressed.
Furthermore, it is necessary to thoroughly prevent voids while preventing warpage from occurring in the semiconductor chip adhesive. However, in the prior art, no one satisfying both of these has been obtained.
JP 2005-183788 A Hitachi Chemical Technical Report No. 47 (2006-7)

In view of the above situation, the present invention provides a cured product after curing having moderate flexibility at room temperature and high temperature, and excellent adhesion between an electrical component such as a semiconductor chip and a substrate, and a semiconductor chip adhered to the substrate. It is an object of the present invention to provide an adhesive for electrical parts that can prevent large warpage of the electrical parts.

The present invention relates to an epoxy compound (A) having a polyether skeleton having 3 to 6 carbon atoms, an aromatic skeleton, and a glycidyl ether skeleton directly connected to the aromatic skeleton (hereinafter also simply referred to as an epoxy compound (A)), carbon An epoxy compound (B) having a glycidyl ether skeleton directly linked to the aliphatic polyether skeleton of formulas 3 to 6 and the aliphatic polyether skeleton (hereinafter also simply referred to as an epoxy compound (B)), a curing agent (C), An adhesive for electronic parts having a polyfunctional epoxy (D) having an epoxy equivalent of 50 to 150 having an aromatic skeleton (hereinafter also simply referred to as a polyfunctional epoxy compound (D)) and / or an inorganic filler, When used as an article, it is an adhesive for electronic parts having a storage elastic modulus at 260 ° C. of 4 MPa or more.

The present inventors are not a mixed system of an acrylic resin and an epoxy compound having a problem such as storage stability but an adhesive for electrical parts mainly composed of an epoxy compound, and the semiconductor chip or the substrate is extremely thin. We have developed an adhesive for electrical parts that can sufficiently prevent warping. As a result, in order to suppress the occurrence of warping even when the semiconductor chip or the substrate is extremely thin, in addition to keeping the storage elastic modulus of the cured product at room temperature below, the adhesive for electrical components It was found that curing at a relatively low temperature in a short time (low temperature curability) is important. This is considered because the electrical component adhesive is cured at a relatively low temperature within a short period of time, thereby reducing the thermal deformation of the resin when cooled from the curing temperature to room temperature. Further, when the curing reaction is fast, the curing reaction is sufficiently completed even at a low temperature, and the chip warp does not increase due to the influence of the subsequent heat process.

As a result of further intensive studies, the epoxy resin having a C3-C6 polyether skeleton, an aromatic skeleton, and a glycidyl ether skeleton directly connected to the aromatic skeleton, which are relatively soft and have excellent low-temperature curability. Using the compound (A), an epoxy compound (B) having an aliphatic polyether skeleton having 3 to 6 carbon atoms and a glycidyl ether skeleton directly connected to the aliphatic polyether skeleton or an epoxy equivalent of 50 to 150 having an aromatic skeleton By using an adhesive for electrical parts whose storage elastic modulus is adjusted at room temperature and around 260 ° C. with a polyfunctional epoxy (D) and / or an inorganic filler, it is possible to prevent the occurrence of voids in the resulting cured product and a semiconductor chip And found that warping can be prevented even when the substrate is extremely thin, and the present invention has been completed. .

The adhesive for electronic components of the present invention contains an epoxy compound (A) having a C3-C6 polyether skeleton, an aromatic skeleton, and a glycidyl ether skeleton directly connected to the aromatic skeleton.
By containing the epoxy compound (A), it is possible to impart flexibility to the resulting cured product and to exhibit quick curability at a relatively low temperature, thus preventing warpage of the resulting cured product. In addition, generation of voids can be prevented.

The epoxy compound (A) has a C3-C6 polyether skeleton.
By having such a skeleton, the obtained cured product has flexibility, and the occurrence of warpage can be reduced.

In the said epoxy compound (A), although it does not specifically limit as said C3-C6 polyether skeleton, A polypropylene glycol skeleton, a polytetramethylene glycol skeleton, etc. are preferable.

The epoxy compound (A) has an aromatic skeleton and a glycidyl ether skeleton directly connected to the aromatic skeleton.
By having such a glycidyl ether skeleton directly linked to the aromatic skeleton, it is possible to exhibit fast curability at a relatively low temperature. By showing fast curability at a relatively low temperature, warpage of the cured product until it returns to room temperature is reduced, and by showing fast curability, moisture contained in the substrate is voided in the adhesive for electronic components of the present invention. It is believed that both warpage and voids can be reduced because they cure faster than they form.

In the epoxy compound (A), the aromatic skeleton is not particularly limited, and may be, for example, a benzene ring, a bisphenol A type, a bisphenol F skeleton, a naphthalene skeleton, or the like.

In the epoxy compound (A), the position in the molecule of the aromatic skeleton and the glycidyl ether skeleton directly connected to the aromatic skeleton is not particularly limited, and the polyether skeleton is present on both sides of the aromatic skeleton. Alternatively, the aromatic skeleton may be provided on both sides of the polyether skeleton.

As for the number average molecular weight of the said epoxy compound (A), a preferable minimum is 800 and a preferable upper limit is 10,000. If it is less than 800, the cured product may be too hard, and if it exceeds 10,000, the viscosity may be too high.

The method for producing the epoxy compound (A) is not particularly limited. For example, an addition reaction of an aromatic compound having two or more hydroxyl groups with glycidyl ether, and a method of adding a polyether skeleton, and the like. Can be mentioned.

It does not specifically limit as a commercial item of the said epoxy compound (A), For example, EXA-4850-150 (made by Dainippon Ink & Chemicals, Inc.) etc. are mentioned.

The adhesive for electronic components of the present invention contains an epoxy compound (B) having an aliphatic polyether skeleton having 3 to 6 carbon atoms and a glycidyl ether skeleton directly connected to the aliphatic polyether skeleton.
By having the epoxy compound (B), the cured product can be given more flexibility than the case where only the epoxy compound (A) is used, and the occurrence of warpage can be reduced moderately. Since the viscosity can be lowered, the coating property is improved.

The epoxy compound (B) has an aliphatic polyether skeleton having 3 to 6 carbon atoms.
By having such a skeleton, the viscosity of the adhesive for electronic components of the present invention can be prevented from becoming too high, and the obtained cured product has excellent flexibility.

In the epoxy compound (B), the aliphatic polyether skeleton having 3 to 6 carbon atoms is not particularly limited, and examples thereof include propylene glycol and polytetramethylene glycol.

As for the number average molecular weight of the said epoxy compound (B), a preferable minimum is 800 and a preferable upper limit is 10,000. If it is less than 800, sufficient flexibility may not be imparted, and if it exceeds 10,000, the viscosity may increase and workability may deteriorate.

It does not specifically limit as a commercial item of the said epoxy compound (B), For example, Epogosay PT (made by a Yokkaichi synthesis company) etc. are mentioned.

The blending amount of the epoxy (B) is not particularly limited, but a preferable lower limit is 30 parts by weight and a preferable upper limit is 200 parts by weight with respect to 100 parts by weight of the epoxy (A). If the amount is less than 30 parts by weight, the effect of flexibility and viscosity may not be obtained. If the amount exceeds 200 parts by weight, the curing reaction rate may decrease, and a sufficient cured product may not be obtained.

The adhesive for electronic components of the present invention contains a curing agent (C).
The curing agent is not particularly limited, but is preferably an acid anhydride curing agent and / or an imidazole compound.

Although it does not specifically limit as said acid anhydride hardening | curing agent, It is preferable to contain the succinic anhydride compound (henceforth only a succinic anhydride compound) represented by following General formula (1).

In General Formula (1), R ¹ represents an alkyl group, an alkenyl group, or an aralkyl group having 11 to 30 carbon atoms.

Further, R ¹ in which the succinic anhydride compound has, in the cured product obtained, exhibits flexibility. That is, since the flexible skeleton which the succinic anhydride compound has in the side chain is added, the obtained cured product can exhibit flexibility as a whole. In this way, a relatively low elastic modulus at room temperature can be ensured.

In general, various curing agents other than the above succinic anhydride compounds are conceivable. However, when a curing agent other than the above acid anhydride is used, the storage modulus in a high temperature region can be increased for the obtained cured product. However, since the storage elastic modulus at room temperature becomes too high, the stress relaxation property cannot be obtained and warping may occur.
As the curing agent, even if the compound having the same flexible skeleton in the side chain of the acid anhydride is not necessarily the same compound as the succinic anhydride compound, it is the same as the adhesive for electronic parts of the present invention. It can be expected to obtain the effect.
Such a compound having a flexible skeleton in the side chain of the acid anhydride is not particularly limited, and examples thereof include, for example, an alkyl group having 10 to 16 carbon atoms, an alkenyl group having 10 to 16 carbon atoms, and 10 to 10 carbon atoms. And acid anhydrides having 16 aralkyl groups and the like.

The succinic anhydride compound is not particularly limited, and examples thereof include dodecenyl succinic anhydride.

The imidazole compound is not particularly limited. For example, 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, 2,4-dimethylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 1 , 2-diethylimidazole, 2-phenyl-4-methylimidazole, 2,4,5-triphenylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-benzyl-2-phenylimidazole, 1- Cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-aryl-4,5-diphenylimidazole, 2 , 4-dia No-6- [2′-methylimidazolyl- (1) ′]-ethyl-S-triazine, 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1) ′]-ethyl -S-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1) ']-ethyl-S-triazine isocyanuric acid adduct, 2-phenyl-4-methyl-5-hydroxymethylimidazole Etc.

Although it does not specifically limit as a compounding quantity of the said hardening | curing agent (C), A preferable minimum is 3 weight part with respect to 100 weight part of said epoxy (A), and a preferable upper limit is 60 weight part. If the amount is less than 3 parts by weight, curing may not proceed sufficiently. If the amount exceeds 60 parts by weight, the unreacted curing agent may be present, thereby lowering the adhesion reliability.

The adhesive for electronic parts of the present invention preferably contains a curing accelerator.
The curing accelerator is not particularly limited, and examples thereof include imidazole-based curing accelerators and tertiary amine-based curing accelerators. Among them, a reaction system for adjusting the curing speed and the physical properties of the cured product. Therefore, an imidazole curing accelerator is preferably used. These hardening accelerators may be used independently and may use 2 or more types together.
The imidazole curing accelerator is not particularly limited, and examples thereof include 1-cyanoethyl-2-phenylimidazole in which the 1-position of imidazole is protected with a cyanoethyl group, and those whose basicity is protected with isocyanuric acid (trade name “2MA- OK ”, manufactured by Shikoku Kasei Kogyo Co., Ltd.). In particular, an imidazole compound having a triazine skeleton is preferable. By using an imidazole compound having such a skeleton, a high curing rate can be obtained even at a relatively low temperature while maintaining storage stability. These imidazole type hardening accelerators may be used independently and may use 2 or more types together.

As for the said hardening accelerator, the minimum with a preferable melting | fusing point is 120 degreeC. By setting the temperature to 120 ° C. or higher, when the electronic component adhesive of the present invention is heated, gelation is suppressed, and the electronic components can be suitably joined and the distance between the electronic components can be adjusted appropriately. Moreover, it is preferable that any one of an acid anhydride hardening | curing agent and a hardening accelerator is a powder.

Examples of the curing accelerator having a melting point of 120 ° C. or higher include 2MZ, 2MZ-P, 2PZ, 2PZ-PW, 2P4MZ, C11Z-CNS, 2PZ-CNS, 2PZCNS-PW, 2MZ-A, 2MZA-PW, and C11Z. -A, 2E4MZ-A, 2MA-OK, 2MAOK-PW, 2PZ-OK, 2MZ-OK, 2PHZ, 2PHZ-PW, 2P4MHZ, 2P4MHZ-PW, 2E4MZ · BIS, VT, VT-OK, MAVT, MAVT-OK (Above, manufactured by Shikoku Kasei Kogyo Co., Ltd.). In particular, a curing accelerator that is stable up to 130 ° C. and activated at 135 to 200 ° C. is preferable. Among those described above, 2MA-OK and 2MAOK-PW are preferable. When these curing accelerators are used, it is possible to achieve both storage stability, stability against heat during the process, and rapid curability.
When the acid anhydride curing agent and the curing accelerator are used in combination, the amount of the acid anhydride curing agent is preferably equal to or less than the theoretically required equivalent to the epoxy group contained in the epoxy compound described above. . If the blending amount of the acid anhydride curing agent exceeds the theoretically required equivalent, chlorine ions may be easily eluted by moisture after curing. That is, if the curing agent is excessive, for example, when the elution component is extracted with hot water from the cured product of the adhesive for electronic components of the present invention, the pH of the extracted water becomes about 4 to 5, and thus the above-described case. Large amounts of chloride ions may elute from epoxy compounds. Accordingly, it is preferable that the pH of pure water after 1 g of the cured product of the adhesive for electronic parts of the present invention is immersed in 10 g of pure water at 100 ° C. for 2 hours is 6-8, and the pH is 6.5-7. .5 is more preferable.

Although it does not specifically limit as a compounding quantity of the said hardening accelerator, A preferable minimum is 1 weight part and a preferable upper limit is 8 weight part with respect to 100 weight part of said epoxy (A). If it is less than 1 part by weight, it may not be sufficiently cured, and if it exceeds 8 parts by weight, sufficient flexibility may not be obtained.

The adhesive for electronic components of the present invention contains a polyfunctional epoxy (D) having an epoxy equivalent of 50 to 150 and / or an inorganic filler having an aromatic skeleton.
By containing the polyfunctional epoxy (D) and / or inorganic filler, the storage elastic modulus at a high temperature around 260 ° C. can be 4 MPa or more. By setting the storage elastic modulus at high temperature to 4 MPa or more, generation of voids can be prevented even when passing through a reflow furnace. Note that 4 MPa corresponds to the vapor pressure of water at 260 ° C.

The lower limit of the epoxy equivalent of the polyfunctional epoxy compound (D) is 50, and the upper limit is 150. By having such an epoxy equivalent, the adhesive for electronic components of the present invention has a glass transition temperature in a predetermined range while the obtained cured product maintains a predetermined high storage elastic modulus at a high temperature (170 ° C. or higher). (Tg) can be achieved. If it is less than 50, the resulting adhesive for electronic components may volatilize when it is cured. If it exceeds 150, a sufficient crosslinking density may not be obtained.
In addition, in this specification, an epoxy equivalent means the value which remove | divided the molecular weight of the polyfunctional epoxy compound by the number of epoxy groups in a molecule | numerator, ie, the molecular weight per epoxy group.
That is, the lower the epoxy equivalent, the higher the epoxy group concentration in the molecule. In general, the lower the epoxy equivalent, the higher the reaction probability with a predetermined acid anhydride curing agent described later, for example, and the curing rate. Becomes higher.

The number average molecular weight of the polyfunctional epoxy compound (D) is not particularly limited, but a preferred lower limit is 150 and a preferred upper limit is 500. If it is less than 150, the resulting adhesive for electronic components may volatilize when cured. When it exceeds 500, the viscosity of the adhesive for electronic components obtained may become higher than necessary. A more preferred lower limit is 200, and a more preferred upper limit is 400.

It does not specifically limit as said polyfunctional epoxy compound (D), For example, a phenol type epoxy compound, a naphthalene type epoxy compound, a biphenyl type epoxy compound etc. are mentioned.
Of these, those having a naphthalene skeleton, a glycidylamine skeleton and the like in the molecule are preferable. By having such a skeleton, more excellent curability can be exhibited.
In particular, those having a glycidylamine skeleton are more preferable. By having a glycidylamine skeleton, it exhibits better curability and can increase the number of functional groups even at low molecular weight, so the viscosity of the adhesive for electronic parts of the present invention can be set to a relatively low desired range. It becomes.

The polyfunctional epoxy compound (D) having the glycidylamine skeleton is not particularly limited, and examples thereof include glycidyloxy-N, N-glycidylaniline.
It does not specifically limit as a commercial item of the polyfunctional epoxy compound which has the said glycidylamine skeleton, For example, EP-3900, EP-3950 (above, all are the Adeka company make) etc. are mentioned.

The polyfunctional epoxy compound (D) is preferably a compound represented by the following general formula (2).

In General Formula (2), R ² is hydrogen or an alkyl group having 1 to 3 carbon atoms.

Although it does not specifically limit as a compounding quantity of the said polyfunctional epoxy (D), A preferable minimum is 5 weight part and a preferable upper limit is 20 weight part with respect to 100 weight part of said epoxy compounds (A). If it is less than 5 parts by weight, a sufficient storage elastic modulus may not be achieved at high temperatures. If it exceeds 20 parts by weight, the desired flexibility may be impaired.

The inorganic filler is not particularly limited, and examples thereof include silica, alumina, titanium dioxide, carbon black, silver and the like.

It does not specifically limit as a commercial item of the said inorganic filler, For example, a silica filler (SE-4050-SEE, the product made from Admatechs) etc. are mentioned.

Although it does not specifically limit as a compounding quantity of the said inorganic filler, A preferable minimum is 5 weight part and a preferable upper limit is 40 weight part with respect to 100 weight part of said epoxy compounds (A). If it is less than 5 parts by weight, a sufficient storage elastic modulus may not be achieved at high temperatures. If it exceeds 40 parts by weight, the desired flexibility may be impaired.

When the adhesive for electronic components of the present invention is a cured product, the storage elastic modulus at 260 ° C. is 4 MPa or more. When it is less than 4 MPa, when the electronic component such as a semiconductor chip and the substrate are bonded using the obtained adhesive for electronic components, peeling may occur during reflow.

The adhesive for electronic parts of the present invention has a preferable lower limit of the storage elastic modulus at 100 ° C of 100 kPa and a preferable upper limit of 10 MPa when cured at 80 ° C, and a cured product when cured at 100 ° C. The preferable lower limit of the storage elastic modulus at 120 ° C. is 200 kPa, and the preferable upper limit is 10 MPa. When cured at 120 ° C., the preferable lower limit of the storage elastic modulus at 170 ° C. is 800 kPa, and the preferable upper limit is 10 MPa. The preferable lower limit of the storage elastic modulus at 260 ° C. of the cured product when cured at 170 ° C. is 4 MPa, and the preferable upper limit is 10 MPa. The adhesive for electronic components of this invention can prevent generation | occurrence | production of a warp while preventing generation | occurrence | production of a void, when the hardened | cured material obtained has such a storage elastic modulus.

The adhesive for electronic components of the present invention has a preferred lower limit of 1 Pa · s and a preferred upper limit of 100 Pa · s, measured using an E-type viscometer at 25 ° C. and 10 rpm. By having such a viscosity, it becomes possible to cope with diversification of coating methods such as a jet dispensing apparatus. If it is less than 1 Pa · s, the shape of the adhesive coating layer after coating by the jet dispensing apparatus may not be suitably maintained at room temperature. If it exceeds 100 Pa · s, the adhesive for electronic parts of the present invention may accumulate at the tip of the nozzle during application by a jet dispensing apparatus, and may not be discharged.

The adhesive for electronic components of the present invention has a preferred lower limit of 0.1 Pa · s and a preferred upper limit of 1 Pa · s measured with an E-type viscometer at 80 ° C. and 10 rpm. By having such a viscosity, it becomes possible to cope with diversification of coating methods such as a jet dispensing apparatus. If it is less than 0.1 Pa · s, even if the viscosity characteristics at room temperature satisfy the above-mentioned range, the adhesive with reduced viscosity wets and spreads at the nozzle tip, and the applicability by the jet dispensing device decreases. There is. If it exceeds 1 Pa · s, a large amount of adhesive adheres to the vicinity of the nozzle discharge port, and the continuous discharge property may deteriorate.

The diameter when the adhesive for electronic components of the present invention is an adhesive layer having a thickness of 10 μm and the cured product obtained by curing the adhesive layer at 170 ° C. for 15 minutes is exposed to a temperature condition of 260 ° C. for 10 seconds. A preferable upper limit of the void generation rate of 100 μm or less is 1 piece / mm ² . When the incidence of voids in the cured product is more than 1 piece / mm ² , when the electronic components are bonded using the adhesive for electronic components of the present invention, the connection reliability between the electronic components is May be insufficient.

The method for producing the adhesive for electronic parts of the present invention is not particularly limited. For example, using a mixer such as a homodisper, a homomixer, a universal mixer, a planetarium mixer, a kneader, or a three-roller, at room temperature, the above The method etc. which mix each predetermined amount, such as an epoxy compound (A), an epoxy compound (B), a hardening | curing agent (C), and a polyfunctional epoxy compound (D), are mentioned.

By using the adhesive for electronic components of the present invention, an electronic component assembly can be produced. Specifically, for example, after the adhesive for electronic components of the present invention is applied between the electronic component and the substrate, the adhesive for electronic components of the present invention is cured by curing the adhesive for electronic components of the present invention. It is possible to manufacture an electronic component assembly comprising an agent, an electronic component bonded through the electronic component adhesive of the present invention, and a base material.

According to the present invention, the cured product after curing has moderate flexibility at room temperature and high temperature, and has excellent adhesion between the electrical component such as a semiconductor chip and the substrate, and the electrical component such as a semiconductor chip adhered to the substrate. It is possible to provide an adhesive for joining electronic parts that can prevent the occurrence of large warping.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

(Example)
According to the composition of Table 1, the materials (parts by weight) shown below were stirred and mixed using a homodisper to prepare electronic component bonding adhesives according to Examples and Comparative Examples.

(1) Epoxy compound (A)
EXA-4850-150 (Dainippon Ink Chemical Co., Ltd.)
EXA-4850-1000 (Dainippon Ink Chemical Co., Ltd.)

(2) Epoxy compound (B)
Polytetramethylene glycol diglycidyl ether (Epogosei PT, manufactured by Yokkaichi Synthesis)
Polyethylene glycol diglycidyl ether (EX-841, Nagase ChemteX)

(3) Curing agent (C)
Methylbutenyltetrahydrophthalic anhydride (YH-306, manufactured by Japan Epoxy Resin Co., Ltd.)
Dodecenyl succinic anhydride (DDSA, Shin Nippon Chemical Co., Ltd.)

(4) Curing accelerator imidazole compound (2MZ-A, manufactured by Shikoku Chemicals)
Imidazole compound (2PHZ, manufactured by Shikoku Chemicals)
Imidazole compound (2MA-OK, manufactured by Shikoku Chemicals)

(5) Polyfunctional epoxy compound (D)
Aniline type trifunctional epoxy (EP-3900S, manufactured by Adeka)
Dicyclopentadiene type epoxy compound (HP-7200, manufactured by Dainippon Ink & Chemicals, Inc.)

(6) Epoxy-modified silica with inorganic filler surface (SE-4050-SEE, manufactured by Admatechs)

(7) Thickener Leoroseal (PM-20L, manufactured by Tokuyama Corporation)

(Evaluation)
The following evaluation was performed about the adhesive agent for electronic component joining prepared in the Example and the comparative example. The results are shown in Table 1.

(1) Adhesive for electronic parts (1-1) Viscosity measurement E-type viscosity measuring device (trade name: VISCOMETER TV-22, manufactured by TOKI SANGYO CO. LTD, rotor used: φ15 mm, set temperature: 25 ° C. and 80 ° C. ) And the viscosity at a rotation speed of 10 rpm was measured.

(1-2) Suitability for jet dispensing Jet dispensing suitability was evaluated using a jet dispensing apparatus (DJ-9000, manufactured by Asymtec Corp.). The parts used were a nozzle (No. 4, 100 μm diameter), a valve (C-03, 380 μm), and a needle assembly (No. 16, 2.4 mm). The discharge conditions are a nozzle temperature of 50 ° C. or 80 ° C., a stroke of 780 μm, a hydraulic pressure of 1000 kPa, a valve pressure of 558 kPa, a valve on time of 5 ms, a valve off time of 5 ms, and a nozzle height of 1.0 mm.
The case where the nozzle temperature was 50 ° C. or 80 ° C. and the discharge could be continued for 30 minutes was indicated as “◯”, and the case where the discharge stopped by 30 minutes was indicated as “X”.

(1-3) Curing speed The curing speed of the obtained adhesive for electronic components was evaluated by gel time at 170 ° C. The gel time is measured by placing a resin paste about 1 mm thick in an aluminum cup (diameter: 2 cm, thickness: about 50 μm) and placing it in an oven at 170 ° C. (SPHH-101, manufactured by ESPEC). Time was defined as gel time. Prior to the measurement, preheating was performed for 60 minutes.

(2) Cured product (2-1) Measurement of glass transition temperature (Tg) Using a viscoelasticity measuring machine (manufactured by IT Measurement Control Co., Ltd.), the obtained adhesive for electronic components was 110 ° C. for 40 minutes, 170 ° C. The temperature at 25 ° C. and 175 ° C. of the cured product cured in minutes, the temperature at the peak of Tan δ when measured at a heating rate of 5 ° C./min, tension, grip width of 24 mm, and 10 Hz is the glass transition point. did.

(2-2) Measurement of storage elastic modulus Using the viscoelasticity measuring machine manufactured by IT Measurement Control Co., Ltd., the adhesives for electronic components prepared in Examples and Comparative Examples were cured at 110 ° C. for 40 minutes and 170 ° C. for 15 minutes. The storage elastic modulus of the cured product at 25 ° C. and 260 ° C. was measured at a heating rate of 5 ° C./min, pulling, grip width of 24 mm, and 10 Hz.

(2-3) Measurement of Void Using the obtained adhesive for electronic parts, a silicon chip and a substrate (manufactured by Daisho Electronics Co., Ltd.) are joined, and an adhesive layer made of an adhesive for electronic parts (adhesive layer) The cured product was obtained by curing at 80 ° C. for 1 hour, 100 ° C. for 1 hour, 120 ° C. for 1 hour, and 170 ° C. for 15 minutes. The cured product was observed for the presence of voids between the chip and the substrate using an ultrasonic imaging device SAT (Scan Acoustic Tomograph, mi-scope hyper II, manufactured by Hitachi Construction Machinery Finetech Co., Ltd.). A case where the number of voids having a diameter of 100 μm or less was 1 piece / mm ² or less was rated as “◯”, and a case where a void having a diameter of 100 μm or less was 1 piece / mm ² or more was shown as “X”.

(3) Electronic component assembly (3-1) Production of semiconductor chip assembly The obtained adhesive for electronic components was filled into a 10 mL syringe (manufactured by Iwashita Engineering Co., Ltd.), and a precision nozzle (manufactured by Iwashita Engineering Co., Ltd., A nozzle tip diameter of 0.3 mm) is attached, and applied on a glass substrate using a dispenser device (SHOT MASTER300, manufactured by Musashi Engineering Co., Ltd.) with a discharge pressure of 0.4 MPa, a gap between the semiconductor chip and the needle of 200 μm, and a coating amount of 5 mg. did. The application amount was set to (application amount to the outer peripheral portion of the joint portion / application amount to the central portion) = 4.
After coating, a semiconductor chip (chip 1) having 172 110 μm pad openings in a peripheral shape (thickness 80 μm, 10 mm × 10 mm square, mesh pattern, aluminum wiring: thickness 0.7 μm, L / S = 15/15, the thickness of the silicon nitride film on the surface: 1.0 μm) was laminated by pressing at a normal pressure of 0.1 MPa for 5 seconds using a flip chip bonder (DB-100, manufactured by Kasuya Kogyo Co., Ltd.). By heating at 110 ° C. for 40 minutes and 170 ° C. for 15 minutes to cure the adhesive for electronic components, a semiconductor chip bonded body was manufactured.

(3-2) Measurement of warp amount of semiconductor chip The warp amount was measured with a laser displacement meter (LT9010M, KS-1100, manufactured by KEYENCE) along the diagonal line of the semiconductor chip of the manufactured semiconductor chip assembly.

(3-3) Wire Bonding Evaluation Wire bonding was performed with a wire having a diameter of 25 μm on the manufactured semiconductor chip bonding material using a wire bonder UTC2000 (manufactured by Shinkawa Co., Ltd.). The wire was pulled at the wire neck portion, and the one cut at the wire neck was marked with ◯, and the one cut at the joined portion was marked with ×.

(3-4) Evaluation of reflow resistance After the produced semiconductor chip joined body is left in a constant temperature and high humidity oven at 85 ° C. and 85% for 24 hours, an IR in which 230 ° C. or higher is 20 seconds or longer and the maximum temperature is 260 ° C. The reflow furnace was charged three times. After the introduction, the presence or absence of reflow cracks in the semiconductor device was observed with an ultrasonic flaw detector (SAT) and evaluated according to the following criteria.
A: Reflow crack occurrence number 0/30
○: Number of reflow cracks generated 1/30
Δ: Number of reflow cracks generated 2/30
X: Number of reflow cracks generated 3/30

According to the present invention, the cured product after curing has moderate flexibility at room temperature and high temperature, and has excellent adhesion between the electrical component such as a semiconductor chip and the substrate, and the electrical component such as a semiconductor chip adhered to the substrate. It is possible to provide an adhesive for electronic parts that can prevent large warpage from occurring.

Claims (6)

An epoxy compound (A) having a C3-C6 polyether skeleton, an aromatic skeleton, and a glycidyl ether skeleton directly connected to the aromatic skeleton;
An epoxy compound (B) having a C3-C6 aliphatic polyether skeleton and a glycidyl ether skeleton directly connected to the aliphatic polyether skeleton;
A curing agent (C);
An adhesive for electronic parts containing a polyfunctional epoxy (D) having an epoxy equivalent of 50 to 150 and / or an inorganic filler having an aromatic skeleton,
An adhesive for electronic parts, wherein the cured product has a storage elastic modulus at 260 ° C of 4 MPa or more. The number average molecular weight of an epoxy compound (A) is 800-10000, and the number average molecular weight of an epoxy compound (B) is 800-10000, The adhesive agent for electronic components of Claim 1 characterized by the above-mentioned. The adhesive for electronic parts according to claim 1 or 2, wherein the curing agent is an acid anhydride curing agent and / or an imidazole compound. The adhesive for electronic parts according to claim 1, 2 or 3, further comprising a curing accelerator. 5. The adhesive for electronic components according to claim 1, wherein the curing accelerator is an imidazole compound having a triazine skeleton. The epoxy compound (B) contains 30 to 200 parts by weight and the curing agent (C) contains 3 to 60 parts by weight with respect to 100 parts by weight of the epoxy compound (A). The adhesive for electronic components according to 3, 4, or 5.