JPH11111760A - Bonding agent for electronic parts and bonding tape for electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce heat absorption of a bonding agent layer during a thermal process, and to improve reliability both at the time of mounting and after mounting, by permitting the bonding agent to contain a group of trihydroxyphenylmethane phenol resin having a structurally large free volume. SOLUTION: Trihydroxyphenylmethane phenol resins are generally represented by formula. The content of a trihydroxyphenylmethane phenol resin should desirably be at 5-15 wt.% in consideration of low-heat shrinkage and insulation reliability of a bonding agent. Less than 5 wt.% content of the phenol resin renders a tape to suffer great warpage, which is liable to cause problems such as a bonding failure ascribed to positional shift of the leads, at the time of bonding an inner lead and an outer lead to a semiconductor chip. On the other hand, a content greater than 15 wt.% is apt to cause the problem of lowering insulation reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for assembling a semiconductor device, such as a TAB (Tape Automated Bondin) suitable for increasing the number of pins, miniaturizing the device, and mounting the device at high density.
g) Adhesives for electronic components suitable for use in methods, etc., and
The present invention relates to a TAB tape and a lead frame fixing tape using this adhesive, and an electronic component adhesive tape used for a method of connecting a lead frame and a TAB tape by wire bonding.

[0002]

2. Description of the Related Art Conventionally, a film tape carrier based on the TAB method has been manufactured through the following processing steps. 1) Drill a sprocket device hole into a TAB tape by stamping. 2) After thermocompression bonding copper foil to the perforated TAB tape,
The adhesive is cured by heating. 3) A photoresist is applied, irradiated with ultraviolet rays or the like through a mask, and then developed. 4) Backing the device hole, etching copper, removing the resist, and removing the backing to create a circuit and apply a solder resist. 5) Perform tin or gold plating. After performing the inner lead bonding of the chip to the tape manufactured through the above steps, the outer lead is cut, and the outer lead is bonded to a printed board or the like,
Seal with resin. Alternatively, after inner lead bonding, sealing is performed with a resin, cutting is performed including peripheral circuits, and outer lead bonding is performed.

[0003] Further, the lead frame fixing tape is taped on lead pins, delivered to a semiconductor maker, and sealed with a resin after mounting an IC. for that reason,
The lead frame fixing tape is required to have insulation reliability and sufficient adhesive strength at a semiconductor level and sufficient heat resistance to withstand heating in a semiconductor device assembly process.

[0004]

In the film tape carrier manufacturing process described above, when the semiconductor chip is subjected to the inner lead bonding and / or the outer lead bonding to the tape, the tape is caused by heat shrinkage of the adhesive. Sledding is a problem. In other words, as the integration and miniaturization continue to increase in the future, warpage of the tape caused by a thermal process during the assembly process has become a major cause of defective manufacturing of semiconductor devices. The warpage of the tape includes the heat shrinkage of the base film itself, but most of the warp is caused by the heat curing process of the adhesive and the subsequent shrinkage due to heat history. In particular, heat shrinkage is largely controlled by the composition of the adhesive.

[0005] As the adhesive for TAB tapes which has been conventionally used, as the degree of integration and the voltage of integrated circuits are increasing, adhesives having higher heat resistance and insulation reliability have been demanded. In many cases, thermal shrinkage was involved due to the composition and reaction mechanism. For example, conventionally, those containing a polyamide resin, an epoxy resin, and a resol-type phenol resin have been used. In a TAB tape using such an adhesive, warpage occurs in the tape on which the pattern is formed, and when the semiconductor chip is subjected to inner lead bonding to the tape, bonding failure, disconnection of the lead after the inner lead bonding, and the like occur. There was a risk of occurrence.

In a conventional tape for fixing a lead frame, an adhesive layer such as a synthetic rubber resin such as polyacrylonitrile, polyacrylate or acrylonitrile-butadiene copolymer is formed on a support such as a polyimide film. Or modified with another resin, or coated with an adhesive mixed with another resin. However, such adhesives have sufficient heat resistance, but there is a problem in that heat shrinkage increases with the improvement in heat resistance, and the position of the lead pin becomes irregular after heating and cooling. Was.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems in the conventional adhesive tapes for electronic parts such as TAB tapes and lead frame fixing tapes. It is an object of the present invention to provide a highly reliable electronic component adhesive and an electronic component adhesive tape at the time of mounting and after mounting by reducing the heat shrinkage of the adhesive layer due to the heat process.

[0008]

Means for Solving the Problems The present inventor has conducted intensive studies to complete an adhesive having low heat shrinkage as well as heat resistance and insulation resistance. Focusing on hydroxyphenylmethane type phenolic resin, as a result of various experiments, it was found that it is most suitable as a resin to be contained in an adhesive. That is,
The adhesive for electronic parts of the present invention is a thermosetting adhesive containing a trihydroxyphenylmethane type phenol resin. Specifically, the trihydroxyphenylmethane type phenol resin used in the present invention generally refers to a resin represented by the following general formula.

[0009]

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[0010]

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[0011]

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[0012]

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The content of the trihydroxyphenylmethane type phenol resin in the present invention is determined by the low heat shrinkage of the adhesive,
In consideration of insulation reliability, the content is desirably 5 to 15% by weight. That is, in the present invention, the content of the trihydroxyphenylmethane type phenol resin is 5% by weight.
If the number is smaller, warpage of the tape becomes large, and problems such as bonding failure due to misalignment of the lead and disconnection of the lead after bonding are liable to occur at the time of inner lead bonding with the semiconductor chip and at the time of outer lead bonding. On the other hand, when the content is more than 15% by weight, a problem such as a decrease in insulation reliability tends to occur. More preferably, the content of the trihydroxyphenylmethane type phenol resin is 5 to 12% by weight.

The components of the adhesive in the present invention include, in addition to the trihydroxyphenylmethane type phenol resin,
A component having a functional group in its structure and reacting with the component itself and / or another component to cure the component can be used. For example, an epoxy resin, a phenol resin other than the above, and a maleimide compound can be used. Less than,
Specific examples thereof will be described.

A. Epoxy resin The epoxy compound that can be used in the present invention must contain two or more epoxy groups in one molecule.
Specifically, allyl glycidyl ether, butyl glycidyl ether, glycidyl methacrylate, 3,4-epoxy-6-methylcyclohexylmethyl-3, 4-epoxy-6-methylcyclohexenecarboxylate, vinylcyclohexenecarboxylate, vinylcyclohexene dioxide, Bisphenol A obtained from dipentenedionoxide, dicyclopentadienedioxide, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, diglycidyl tetrahydrophthalate, phenol novolak epoxy resin, triglycidyl isocyanate bisphenol A and epichlorohydrin Bisphenol A type epoxy resin such as diglycidyl ether, epoxidized cresol novolak resin, trihydric Polyfunctional epoxy resins represented by hydroxyphenyl methane type epoxy resins, etc. The epoxy compound of the epoxy compound was partially modified with fatty acids are exemplified. Furthermore, epoxy compounds having other structures, for example, various elastomer-modified epoxy resins such as silicon, NBR, SBR, and dimer acid can be used in combination.

B. Phenol resin Examples of the phenolic resin that can be used in the present invention include alkylphenol resin, paraphenylphenol resin, novolak phenol resin such as bisphenol A type phenol resin and alkylphenol resin, cresol type phenol resin, resol phenol resin such as bisphenol A type phenol, and polyphenol resin. Known phenol resins such as phenyl paraphenol resin are exemplified.

C. Maleimide compound The maleimide compound that can be used in the present invention has at least one maleimide group as a functional group in the basic skeleton, and generally includes bismaleimides. Specifically, N, N'-m-phenylenebismaleimide, N, N'-m-toluylenebismaleimide,
N, N'-4,4-biphenylenebismaleimide, N,
N'-4,4 '-[3,3'-dimethylbiphenylene] bismaleimide, N, N'-[3,3-dimethyldiphenylmethane] bismaleimide, N, N'-4,4 '
-[3,3-diethyldiphenylmethane] bismaleimide, N, N'-4,4'-diphenylmethanebismaleimide, N, N'-4,4'-diphenylpropanebismaleimide, N, N'-4,4 ' -Diphenylether bismaleimide, N, N'-3,3'diphenylsulfonebismaleimide, N, N'-4,4'-diphenylsulfonebismaleimide and the like.
Further, the adhesive of the present invention may contain an imidazole compound as a curing accelerator.

D. Electronic Component Adhesive Tape An electronic component adhesive tape can be formed by providing the above-described adhesive of the present invention as an adhesive layer on an insulating film. The thickness of the adhesive layer is preferably 6 to 40 μm, more preferably 10 to 20 μm. Since the adhesive layer is in direct contact with the insulating film, it shows high adhesiveness even at high temperatures, shows high adhesive strength with the insulating film, and has high adhesiveness with copper foil and the like when processing into a film carrier. It is required that the chemicals to be exposed have excellent chemical resistance. Further, since the film carrier is required to have processability such as stamping, the adhesive layer after curing must have flexibility. In order to satisfy such conditions, in the present invention, a polyamide resin, a polyamide-imide resin,
Polyimide resin, polyester resin, NBR, SBR,
It is preferable to include at least one kind of thermoplastic resin such as polyvinyl acetal resin.

The insulating film constituting the adhesive sheet for electronic parts of the present invention preferably has a thickness of 25 to 188 μm, and more preferably 50 to 125 μm. As the insulating film, an insulating film made of a heat-resistant plastic film such as polyimide, polyetherimide, polyphenylene sulfide, or polyether ketone, or a composite heat-resistant film such as an epoxy resin-glass cloth or an epoxy resin-polyimide-glass cloth can be used.

A peelable protective film (protective layer) can be provided on the surface of the adhesive layer of the adhesive sheet for electronic parts. This protective film protects the adhesive layer until the copper foil or the like is adhered to the adhesive layer, and is peeled off when the copper foil or the like is adhered. The preferred thickness of the protective film is 15 to 50 μm. As a material for the protective film, for example, a film such as polyethylene, polyethylene terephthalate, or polypropylene can be used. In order to form the protective film so that the protective film can be peeled, the protective film may be subjected to a peeling treatment.

E. Next, the method for producing the adhesive tape for electronic parts of the present invention is described by TA.
This will be described by taking the B tape as an example. First, (a) an adhesive having a predetermined composition is applied on the protective film so that the film thickness after drying is in the above-mentioned range, and an adhesive layer is formed.
At this time, in order to obtain a semi-cured state, 100 to 150
Dry under heating conditions at 5 ° C. for 5 minutes. Next, (b) an insulating film is superimposed on the surface of the formed adhesive layer,
(C) A thermocompression bonding is performed at 100 to 130 ° C. under a condition of 1 kg / cm ² or more, and (d) a TAB tape in which a protective film is laminated on an insulating film via an adhesive layer. The obtained TAB tape is, for example, 3 to 30 mm in width and 200 mm in width.
It has a length of 0 to 300 m and is wound around a winding shaft and stocked.

[0022]

The present invention will be described below with reference to examples. In the following description, “parts” means “parts by weight”, and “%” means “% by weight”. Numerical values in parentheses indicate parts by weight of solids. Example 1 An adhesive layer forming paint having the following composition was applied to a protective layer made of polyethylene terephthalate having a thickness of 38 μm, and dried at 130 ° C. for 5 minutes.
μm adhesive layer, and further 25 μm thick
The protective film made of polyethylene terephthalate was provided to prepare an adhesive film.

45% (11.25 parts) of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin (“Macromelt 6239” manufactured by Henkel Japan) • Bismaleimide resin (“BMI-MP” manufactured by Mitsui Toatsu Chemicals, Inc.) ) 20% tetrahydrofuran solution 17 parts (3.4 parts) · Epoxy resin (“Epicoat 1031S” manufactured by Yuka Shell Co., Ltd.) 50% methyl ethyl ketone solution 11 parts (5.5 parts) Essential component in the invention: 50% methanol solution of trihydroxyphenylmethane-type phenol resin described in [Chemical Formula 1] 5.5 parts (2.75 parts) 22% of 1% 2-ethyl-4-methylimidazole in 1% methyl ethyl ketone solution (0.22 parts) (Phenol resin in the above composition is 12.0%)

Example 2 An adhesive film of Example 2 was prepared in the same manner as in Example 1 except that the coating composition for forming the adhesive layer had the following composition.・ 33 parts (16.5 parts) of 25% isopropyl alcohol / toluene mixed solution of polyamide resin (“Macromelt 6240” manufactured by Henkel Japan) ・ 50% methyl ethyl ketone solution of epoxy resin (“TMII574” manufactured by Sumitomo Chemical Co., Ltd.) 13 parts (6.5 parts) ・ Resol type phenol resin (“BKM2620” manufactured by Showa Polymer Co., Ltd.) 50% methyl ethyl ketone solution 6 parts (3 parts) ・ Novolak type phenol resin (“CRG951” manufactured by Showa Polymer Co., Ltd.) 6 parts (3 parts) of a 50% methyl ethyl ketone solution 8 parts (4 parts) 2-ethyl- of a 50% methanol solution of a phenol resin (an essential component in the present invention: a trihydroxyphenylmethane type phenol resin described in Chemical Formula 2) 33 parts of a 1% solution of 4-methylimidazole in methyl ethyl ketone (0. 3) (12.0 percent phenolic resin in the composition)

Example 3 An adhesive film of Example 3 was prepared in the same manner as in Example 1, except that the coating composition for forming the adhesive layer had the following composition.・ 50 parts (12.5 parts) of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin (“Macromelt 6240” manufactured by Henkel Japan) ・ 50% methyl of an epoxy resin (“Epicoat 157S65” manufactured by Yuka Shell) 12 parts (6 parts) of ethyl ketone solution, 7 parts (3.5 parts) of a 50% methyl ethyl ketone solution of resole type phenol resin (“CKM908” manufactured by Showa Polymer Co., Ltd.), and phenol resin (an essential component in the present invention: 6 parts (3 parts) of a 50% methanol solution of the above-mentioned trihydroxyphenylmethane-type phenol) and 25 parts (0.25 parts) of a 1% methyl ethyl ketone solution of 2-ethyl-4-methylimidazole (the phenol resin in the above composition is 11.9%)

Example 4 An adhesive film of Example 4 was produced in the same manner as in Example 1, except that the coating composition for forming the adhesive layer had the following composition.・ 50 parts (12.5 parts) of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin (“Macromelt 6239” manufactured by Henkel Japan) ・ 50% methyl ethyl ketone solution of an epoxy resin (“EOCN1020” manufactured by Nippon Kayaku) 14 parts (7 parts) of a 50% methanol solution of a phenol resin (an essential component in the present invention: trihydroxyphenylmethane-type phenol described in Chemical Formula 4) 6 parts (3 parts) -novolak-type phenol resin ("BRG555" Showa) 5 parts (2.5 parts) of a 50% methyl ethyl ketone solution of a polymer company) 25 parts (0.25 parts) of a 1% methyl ethyl ketone solution of 2-ethyl-4-methylimidazole (the phenol resin in the above composition is 11.9) %)

Example 5 An adhesive film of Example 5 was produced in the same manner as in Example 1 except that the coating composition for forming the adhesive layer had the following composition. 44% (11 parts) of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin ("Macromelt 6239" manufactured by Henkel Japan) 20% tet of a bismaleimide resin ("BMI-MP" manufactured by Mitsui Toatsu Chemicals, Inc.) 21 parts (4.2 parts) of a lahydrofuran solution, 12 parts (6 parts) of a 50% methyl ethyl ketone solution of an epoxy resin (“Epicoat 1031S” manufactured by Yuka Shell Co., Ltd.), and a phenol resin (an essential component in the present invention: 1] Triethanoloxyphenylmethane type phenol resin) described above 1 part (0.5 part) methanol solution 22 parts (0.22 part) 1% 2-ethyl-4-methylimidanol in 1% methyl ethyl ketone solution (The phenolic resin in the above composition is 2.3%)

Example 6 An adhesive film of Example 6 was produced in the same manner as in Example 1 except that the paint for forming the adhesive layer had the following composition. 44% (11 parts) of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin ("Macromelt 6239" manufactured by Henkel Japan) 20% tet of a bismaleimide resin ("BMI-MP" manufactured by Mitsui Toatsu Chemicals, Inc.) 19 parts (3.8 parts) of a lahydrofuran solution, 12 parts (6 parts) of a 50% methyl ethyl ketone solution of an epoxy resin (“Epicoat 1031S” manufactured by Yuka Shell Co., Ltd.), and a phenol resin (an essential component in the present invention: 3] (1.5 parts) of a 50% methanol solution of trihydroxyphenylmethane type phenol resin described in [1]; 22 parts (0.22 parts) of a 1% methyl ethyl ketone solution of 2-ethyl-4-methylimidazole (the above composition) 6.6% in phenolic resin)

Example 7 An adhesive film of Example 7 was produced in the same manner as in Example 1, except that the coating composition for forming the adhesive layer had the following composition. -46 parts (11.5 parts) of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin ("Macromelt 6239" manufactured by Henkel Japan)-20 of a bismaleimide resin ("BMI-MP" manufactured by Mitsui Toatsu Chemicals, Inc.) 9 parts (4.5 parts) of a 50% methyl ethyl ketone solution of an epoxy resin (“Epicoat 1031S” manufactured by Yuka Shell Co.) 15 parts (3 parts) of a 15% tetrahydrofuran solution and a phenol resin (an essential component in the present invention: 8 parts (4 parts) of a 50% methanol solution of trihydroxyphenylmethane-type phenol resin according to [Chemical Formula 1], 22 parts (0.22 parts) of a 1% solution of 2-ethyl-4-methylimidazole in methyl ethyl ketone (the above composition) Phenolic resin in 17.2%)

Comparative Example 1 An adhesive film of Comparative Example 1 was prepared in the same manner as in Example 1, except that the coating composition for forming the adhesive layer had the following composition. -Polyamide resin ("Macromelt 6239", manufactured by Henkel Japan) 53% 25% isopropyl alcohol / toluene mixed solution-Epoxy resin ("Epicoat 828" manufactured by Yuka Shell Co., Ltd.) 7 parts-Resol type phenolic resin ("CKM1634") 8 parts of 50% methyl ethyl ketone solution of Showa Polymer Co., Ltd. ・ 5 parts of 50% methyl ethyl ketone solution of novolak type phenol resin (“CKM2400” manufactured by Showa Polymer Co., Ltd.) ・ 1% methyl ethyl ketone solution of 2-ethyl-4-methylimidazole 27 Department

Comparative Example 2 An adhesive film of Comparative Example 2 was prepared in the same manner as in Example 1, except that the coating composition for forming the adhesive layer had the following composition. 45 parts of a 25% isopropyl alcohol / toluene mixed solution of a polyamide resin ("Macromelt 6239" manufactured by Henkel Japan) 45 parts 17 parts of a 20% tetrahydrofuran solution of a bismaleimide resin ("BMI-MP" manufactured by Mitsui Toatsu Chemicals, Inc.) 11 parts of 50% methyl ethyl ketone solution of epoxy resin ("Epicoat 1031S" manufactured by Yuka Shell Co., Ltd.) 5 parts of 50% methanol solution of novolak type phenol resin ("CKM2432" manufactured by Showa Polymer Co., Ltd.) 2-ethyl-4 -22 parts of a 1% solution of methylimidazole in methyl ethyl ketone

(1) Preparation of Sample for Measurement of Heat Shrinkage Next, both sides of the protective layer of the adhesive films prepared in Examples and Comparative Examples were peeled off, and 1 oz of electrolytic copper foil (thickness of 35 to 4
0 μm) on both sides, 130 ° C., 1 kg / cm
^The heating and pressurizing treatment was performed under the conditions of ² . Then 70 ° C
For 4 hours, and the temperature was increased from 70 ° C. to 160 ° C. at a constant speed over 8 hours, and then heated at 160 ° C. for 6 hours to cure the adhesive layer. Further, one side of the copper foil surface was removed by etching, and this was used as a sample for measuring heat shrinkage.

(2) Preparation of Sample for Bias Test Further, one side of the protective layer of the adhesive film prepared in each of Examples and Comparative Examples was peeled off, and an insulating film made of a polyimide film having a thickness of 75 μm was laminated thereon. ,
It was heated and pressed under the condition of 1 kg / cm ² to prepare a TAB tape. Next, the protective film of this TAB tape is peeled off, and 1 oz of electrolytic copper foil (thickness: 35 to 40 μm)
And heat-pressurized at 130 ° C. and 1 kg / cm ² . Thereafter, the mixture was further heated at 70 ° C. for 4 hours, then heated at a constant speed from 70 ° C. to 160 ° C. over 8 hours, and heated at 160 ° C. for 6 hours to cure the adhesive layer. Further, a photoresist film is formed on the copper foil by a conventional method and processed, the copper foil is etched, a comb-shaped circuit is formed, and a film carrier tape is produced.
A sample for a test (bias test) was used.

(Characteristics Test) The following property evaluation test was performed on the heat shrinkage measurement samples obtained from the adhesive films of Examples 1 to 7 and Comparative Examples 1 and 2. 1) Measurement of heat shrinkage The adhesive tape was cut into dimensions of 40 mm in length and 40 mm in width. The cut adhesive tape was left for 48 hours or more in an atmosphere at a room temperature of 23 ° C. and a relative humidity of 65%. The adhesive tape was placed on a table with the adhesive side down, and the curl height was measured with a microscope at the depth of focus. By the way, in this test, a substrate which affects the heat shrinkage such as a polyimide film is not used, so that the curl height measured in this test is all that of the adhesive itself.

2) PCBT Test (Bias Test) For each of the tape samples of Examples 1 to 7,
A test was performed to measure the time at which the electrical resistance suddenly dropped. The test conditions were 130 ° C. /
85% RH / 2.7 atm, line / line width 50 μm / 1
A voltage of 100 V was applied to a 00 μm comb circuit. Table 1
2 shows the results of curl measurement and the time required for the electric resistance value to decrease in the PCBT test. Table 1 also shows the content of the phenol resin of the present invention.

As is clear from Table 1, the adhesive tape for electronic parts of the present invention has a lower curl height as compared with the comparative example.
Excellent heat shrinkage was exhibited. Further, even in the PCBT test, the electric resistance does not decrease for a long time, and the device has sufficient electric reliability for practical use. In particular, in Examples 1 to 4 and 6 in which the content of the trihydroxyphenylmethane-type phenol resin is 5 to 15% by weight, the electric resistance does not decrease for an extremely long time and shows excellent low heat shrinkage. Was confirmed.

[0037]

[Table 1]

[0038]

As described above, in the present invention,
Since the adhesive contains a trihydroxyphenylmethane-type phenol resin, the adhesive has excellent low heat shrinkage after thermal curing and subsequent thermal processes, and can improve electrical reliability. Therefore, it is possible to reduce the occurrence of manufacturing defects when performing the inner lead bonding and the outer lead bonding between the adhesive tape and the chip, and it is possible to maintain the electrical reliability for a long time.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/52 H01L 21/52 G // C08G 8/04 C08G 8/04 (72) Inventor Takushi Shiozawa Yomune, Shizuoka-shi, Shizuoka 3-1 Tomoecho, Electronic Materials Division, Hamakawa Paper Mills Co., Ltd. (72) Inventor: Takeshi Yoshioka 3-1, Tomoe Tomoecho, Shizuoka-shi, Shizuoka Prefecture, Electronic Materials Division, Hamakawa Paper Co., Ltd. (72) Inventor: Hiromi Yamada 3-1 Yomomochi-cho, Shizuoka-shi, Shizuoka Pref.

Claims (6)

[Claims] 1. An adhesive for electronic parts, comprising a trihydroxyphenylmethane type phenol resin. 2. The electronic component adhesive according to claim 1, further comprising an epoxy resin. 3. The adhesive for electronic components according to claim 1, further comprising a polyamide resin. 4. The adhesive for electronic parts according to claim 1, wherein said trihydroxyphenylmethane type phenol resin is contained in the adhesive in an amount of 5 to 15% by weight. 5. An adhesive tape for electronic parts, comprising an insulating film provided with an adhesive layer comprising the adhesive according to claim 1. 6. The adhesive tape for electronic parts according to claim 5, wherein a peelable protective layer is provided on the surface of the adhesive layer.