WO2005100500A1

WO2005100500A1 - Adhesive tape

Info

Publication number: WO2005100500A1
Application number: PCT/KR2005/001081
Authority: WO
Inventors: Sang-Kyun Kim; Jeong-Yeol Moon; Chang-Beom Chung; Jong-Min Park
Original assignee: Kolon Industries Inc.
Priority date: 2004-04-16
Filing date: 2005-04-14
Publication date: 2005-10-27
Also published as: KR20050100918A; TW200535003A; JP2007532747A

Abstract

The present invention provides an adhesive tape prepared by coating the one side or both sides of a substrate film with an adhesive composition including an acrylonitrile-butadiene copolymer or an acrylonitrile-butadiene-acrylic acid terpolymer containing carboxyl groups, an epoxy resin, a modified epoxy resin, a curing agent, an antioxidant, a filler, and other additives, the adhesive tape being excellent in thermal shrinkage and outgas rate to guarantee a high reliability in the semiconductor chip manufacturing process.

Description

ADHESIVE TAPE

Technical Field The present invention relates to an adhesive tape including an adhesive layer that is formed by coating an adhesive composition on the one side or both sides of a substrate film. More particularly, the present invention relates to an adhesive tape used to fix leads for resin-molded packaging systems.

Background Art Recently the trend of high performance, high function and high density of the electronic devices has been accelerated in accordance with the demands for mass data communications, large capacity and high speed for data transmission and digitalization. For this purpose, the demands for miniaturization of fine semiconductor components and high-density mounting techniques request an adhesive and a material of adhesive tapes to have higher performance such as heat resistance, insulation capacity and applicability to the process than the conventional adhesives. The conventional adhesive tapes used for resin-molded semiconductor components include lead-fixing adhesive tapes, TAB tapes, etc. As shown in FIG. 1. which presents the general view of a lead frame, a lead- fixing adhesive tape 2 fixes the lead position of the lead frame in the assembly process of the lead frame and semiconductor chips to facilitate the assembly process and thereby to enhance the yield and the productivity of the assembly process. Generally, a lead frame manufacturer puts the lead-fixing adhesive tape onto the lead frame, and a semiconductor manufacturer mounts a semiconductor chip using the adhesive tape and packages it with a chip-protection resin. Therefore, the lead-fixing adhesive tape is required to have a sufficiently high resistance to the heat possibly generated from the semiconductor chip and a high reliability, as well as an adhesive strength high enough to fix the leads. In addition, the adhesive tape must have good thermal shrinkage and outgas rate so as to minimize the shifting of the leads caused by the thermal shrinkage of the adhesive tape and the cracks on the chip-protection resin caused by the outgas during a sealing with the protection resin. The conventional adhesive tapes used for the above applications are prepared by coating various adhesive compositions on a heat-resistant substrate film such as a polyamide or polyimide film, or by semi-hardening an adhesive on such a substrate film. Korean Patent Publication No. 1998-16625 discloses, for example, an adhesive composition that includes an acrylonitrile having C -C_IQ alkyl groups; an acrylic resin prepared from a monomer including acrylate, acrylic acid, methacrylic acid, and hydroxyethylacrylate, or hydroxyethylmethacrylate; an epoxy resin including bisphenol- based epoxy, and cresol-novolak-based epoxy; a curing agent; and a silicon resin. Japanese Patent Laid Open No.1995-74213 proposes a technology in which a polyamide resin and a bismaleimide resin are added to lower the chloride concentration to 20 ppm so as to solve the problem in regard to insulation aging of the conventional epoxy resin resulting from a low electric resistance due to the existence of chlorine impurities. In addition, Japanese Patent Laid Open No.1994- 172524 discloses a soluble polyimide resin applicable to electrical and electronic components. However, these conventional adhesive tapes are susceptible to thermal shrinkage in the high-temperature mounting process subsequent to the taping process to cause the shifting of leads or a short circuit from the shifting of leads, and also to outgas from the adhesive layer to produce cracks in the course of the resin molding process after the final mounting process. Accordingly, there is a demand for adhesive tapes that overcome the poor characteristics of the conventional adhesive tapes in regard to thermal shrinkage and outgas rate. In an attempt to manufacture an adhesive tape excellent in reliability such as thermal shrinkage and outgas characteristic as can be used for the manufacturing process of semiconductor chips, the inventors of the present invention have found out that an adhesive tape having an adhesive layer with the one side or both sides of a substrate film coated with an adhesive composition, which includes an acrylonitrile-butadiene copolymer or an acrylonitrile-butadiene-acrylic acid terpolymer, an epoxy resin, a modified epoxy resin, a curing agent, an antioxidant, a filler, and other additives, is excellent in properties such as thermal shrinkage and outgas rate, resulting in a high reliability. It is therefore an object of the present invention to provide an adhesive tape having a high reliability thanks to its excellent thermal shrinkage and outgas rate. The adhesive tape of the present invention excellent in reliability, which adhesive tape has an adhesive layer coated on the one side or both sides of a substrate film, exhibits a thermal shrinkage of 0.01 to 0.15 % and a outgas rate of 0.1 to 1.3 %.

Disclosure of Invention Hereinafter, the present invention will be described in detail as follows. The adhesive tape of the present invention, which has an adhesive layer coated on the one side or both sides of a substrate film, exhibits a thermal shrinkage of 0.01 to 0.15 % and a outgas rate of 0.1 to 1.3 %. The specific examples of the substrate film of the present invention may include polyethyleneterephthalate (PET) film, polypropylene (PP) film, polystyrene (PS) film, polycarbonate (PC) film, polymethylmethacrylate (PMMA) film, polyethylenenaphthalate film, polyetherimide (PEI) film, polypphenylenesulfide (PPS) film, polyimide (PI) film, polyetherketone (PEK) film, polyetheretherketone (PEEK) film, and a composite heat- resistant material such as epoxy resin-glass fabric or epoxy resin-polyimide-glass fabric. Among these substrate film materials, most preferred is polyimide film excellent in the aspect of heat resistance with the smallest difference in the thermal expansion coefficient at a high temperature. The thickness of the substrate film of the present invention is preferably in the range of 10 to 100 μm. The one side or both sides of the substrate film is coated with an adhesive composition to form an adhesive layer of which the dry thickness is preferably in the range of 5 to 40 μm. The adhesive composition coated on the adhesive layer in the present invention includes an acrylonitrile-butadiene copolymer or an acrylonitrile-butadiene-acrylic acid terpolymer, which contains carboxyl groups at the end of its chain, an epoxy resin, a modified epoxy resin, a curing agent, an antioxidant, a filler, and other additives. The acrylonitrile-butadiene copolymer or the acrylonitrile-butadiene-acrylic acid terpolymer used in the present invention has a weight average molecular weight of 20,000 to 1,000,000 and contains carboxyl groups at the end of its chain. The existence of carboxyl groups at the end of the chain contributes to the promotion of adhesive strength resulting from polar groups. Heat resistance and adhesive strength may decrease when the weight average molecular weight of the copolymer or the terpolymer is less than 20,000. Also, it is difficult to form the adhesive layer by coating, with the copolymer or the terpolymer having a weight average molecular weight exceeding 1,000,000. Preferably, a mixture of epoxy resin and modified epoxy resin is used so as to provide excellent adhesive strength and heat resistance of the adhesive tape in the present invention. Preferably, the specific examples of the epoxy resin may include at least one selected from bisphenol A type epoxy, or bisphenol F type epoxy. Preferably, the specific examples of the modified epoxy resin may include at least one selected from tetrabromophthalic anhydride epoxy resin, phenoxy resin, phenol- novolak epoxy resin, cresol-novolak epoxy resin, rubber-modified epoxy resin, or hydrogenated bisphenol A type epoxy resin. The use of an epoxy resin alone in the adhesive composition of the present invention results in poor heat resistance, while the use of a modified epoxy resin alone provides poor adhesive strength between the adhesive layer of the adhesive tape and an inorganic object, providing no adhesiveness. The epoxy resin used in the present invention is not specifically limited, because its epoxy terminal groups function. The amount of the epoxy resin added is preferably 1 to 15 parts by weight with respect to 100 parts by weight of the copolymer or the terpolymer. With less than 1 part by weight of the epoxy resin, adhesive strength is so poor. However, when more than 15 parts by weight of the epoxy resin is added, the adhesive layer is ready to bled out in the adhering process. The weight average molecular weight of the epoxy resin used in the present invention is 200 to 20,000, and preferably 1,000 to 5,000. With the molecular weight of the epoxy resin being less than 200, heat resistance and impact resistance may decrease.

However, with the molecular weight of the epoxy resin exceeding 20,000, adhesive strength is lowered with a deterioration of the fluidity of the adhesive composition, which problem is disadvantageous in the process of forming the adhesive layer. The added amount of the modified epoxy resin is preferably 1 to 200 parts by weight with respect to 100 parts by weight of the copolymer. With less than 1 part by weight of the modified epoxy resin, heat resistance deteriorates. However, when more than 200 parts by weight of the modified epoxy resin is added, the adhesive composition is ready to be peeled off from the substrate film. The epoxy resin and the modified epoxy resin as used in the present invention are semi-cured into the B stage and applied to the subsequent adhering process. In this regard, at least one curing agent selected from acid anhydrides, amine-based curing agents, or acid-based curing agents is used so as to semi-cure the epoxy resin and the modified epoxy resin. The specific examples of the curing agent as used herein may include acid anhydrides such as phthalic anhydride, tetrachlorophthalic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, himic anhydride, pyromellitic dianhydride, methylhexahydrophthalic anhydride, maleic anhydride, or methyltetrahydrophthalic anhydride; amines such as diethylene triamine (DETA), triethylene tetramine (TETA), diethylamino propylamine (DEAPA), methane diamine (MDA), N-aminoethyl piperazine (N-AEP), M-xylene diamine (MXDA), isophorone diamine (IPDA), metaphenylene diamine (MPD), 4,4'-dimethyl aniline (DAM or DDM), diamino diphenyl sulfone (DDS), dimethyl aminomethyl phenol (DMP-10), tris-(dimethylaminomethyl) phenol (DMP-30), salts of DMP-30, or benzyl dimethyl amine (BDMA); or acids such as xylene sulfuric acid. The preferred curing agents for the epoxy resin are amine-based curing agents.

The specific examples of the amine-based curing agent as used herein may include secondary or tertiary amines such as m-xylene diamine (MXDA), isophorone diamine

(IPDA), metaphenylene diamine (MPD), 4,4 '-dimethyl aniline (DAM or DDM), diamino diphenyl sulfone (DDS), dimethyl aminomethyl phenol (DMP-10), tris- (dimethylaminomethyl) phenol (DMP-30), salts of DMP-30, or benzyl dimethyl amine (BDMA), which amines are used to reduce the reaction time, forming a three-dimensional cross-linking. According to the present invention, the curing agent is added in an amount of, with respect to 100 parts by weight of the epoxy resin and the modified epoxy resin, 0.01 to 100 parts by weight, and preferably 0.1 to 70 parts by weight. With less than 0.01 part by weight of the curing agent used, the hardening effect is unsatisfied. However, when the added amount of the curing agent exceeds 100 parts by weight, the residue of the curing agent may cause an ageing of properties. In the present invention, phenols or aromatic amines are added as an antioxidant so as to prevent exfoliation of copper in the subsequent process due to the oxidation of the lead frame after taping the adhesive tape on the lead frame. The specific examples of the antioxidant as used herein may include ethyl ene bis(oxyethylene)bis-(2-(5-tertiary-butyl- 4-hydroxy-m-toryl)-proρionate), calcium diethyl bis(((3,5-bis(l,l-dimethylethyl)-4- hydroxyphenyl)methyl)phosphonate), octadecyl-3-(3,5-di-tertiary-butyl-4- hydroxyphenyl)-propionate, 3,3 ',3 ',5,5 ',5 '-hexa-tertiary-butyl-a,a',a'-(mesitylene-2,4,6- tril)tri-p-cresol, benzene propanoic acid, 3,5-bis(l,l-dimethyl-ethyl)-4-hydroxy-C7-C9 branched alkyl ester, 4,6-bis(octylthiomethyl)-o-cresol, pentaerythritol tetrakis(3-(3,5-di- tertiary-butyl-4-hydroxyphenyl)propionate), tris(2,4-di-tertiary-butylphenyl)phosphate, 6,6 ^r-di-tertiary-butyl-2,2 '-thiodi-p-cresol, octadecyl-3-(3 ,5.rdi-tertiary-butyl-4- hydroxyphenyl)-propionate, or N,N'-hexane-l,6-diylbis(3,5-di-tertiary-butyl-4- hydroxyphenyl propionamide). At least one of these antioxidants is added in an amount of 0.01 to 30 parts by weight with respect to 100 parts by weight of the whole solid content in the adhesive composition. With less than 0.01 part by weight of the antioxidant used, there is no oxidation inhibition effect. But, when the added amount of the antioxidant exceeds 30 parts by weight, non-uniform hardening of the adhesive layer can occur. In addition, fillers may be used for the purpose of providing good processability of the adhesive layer in the high-temperature and high-pressure adhering process and manufacturing process. Preferably, the filler has a particle size of 0.5 to 5 μm. The filler may include at least one selected from calcium carbonate, zinc oxide, silica, alumina, diamond powder, quartz powder, or zircon powder. The added amount of the filler is in the range of 0.5 to 15 parts by weight with respect to 100 parts by weight of the whole solid content in the adhesive composition. If necessary, the adhesive composition of the present invention may include the following additives as well as the components mentioned above. All the additives must be non-ionic and include an extremely small amount of impurities. More specifically, thiuram, zinc oxide, or peroxides may be used as a vulcanizing agent for the acrylonitrile-butadiene copolymer or the acrylonitrile-butadiene-acrylic acid terpolymer in an amount of 0.5 to 10 parts by weight with respect to the binder polymer. When the content of the vulcanizing agent is out of the above range, the adhesive layer loses its adhesive function because of the excessive cross liking of the copolymer. In addition, a phosphine-based flame retardant may be used so as to enhance the fire retardancy of the adhesive layer. The flame retardant includes phosphine-containing compounds such as 9,10-dihydro-9-oxy-10-phosphaphenanthrene-10-oxide, 3- hydroxyphenyl phosphynylpropanoic acid, or diphenyl- 1-1,2-di-hydroxy ethyl phophine oxide. The amount of the flame retardant added is 0.01 to 20 parts by weight, and preferably 0.02 to 10 parts by weight with respect to 100 parts by weight of the binder polymer. With less than 0.01 part by weight of the flame retardant used, the fire retardancy is not improved. However, when the added amount of the flame retardant exceeds 20 parts by weight, the adhesive strength decreases and it is economically unfavorable. The method for preparing the adhesive composition can be described as follows. Copolymer or terpolymer containing carboxyl groups at the end of its chain, an epoxy resin, a modified epoxy resin, a curing agent, and an antioxidant are dissolved in a solvent. The mixture solution is pre-cured by stirring and kept still to prepare the adhesive composition having enhanced low-temperature curability. The specific examples of the solvent as used herein may include toluene, heptane, hexane, xylene, methylethylketone, tetrahydrofurane, n-methylpyrolidone, dimethylformamide, dimethyl acetamide, etc. The preferred solvents are toluene, xylene, or heptane. At least two of those solvents can be mixed in use. The viscosity of the mixed solution is in the range of 10 to 10,000 cps, and preferably 100 to 5,000 cps, in which it is easy to form an adhesive layer by coating. The adhesive composition thus prepared is coated on the one side or both sides of a target substrate with a comma knife. The coated film is dried and semi-cured to complete the final adhesive layer. The adhesive tape of the present invention has a 0.01 to 0.15% of heat shrinkage, and 0.1 to 1.3% of outgas. Therefore, it can prevent the shift of the leads caused by the thermal shrinkage of the adhesive tape and the cracks on the chip-protection resin caused by outgas during a sealing with the protection resin.

Best Mode for Carrying out the Invention Hereinafter, the present invention will be described in detail by way of the following examples, which are not intended to limit the scope of the present invention.

Example 1 150 g of an acrylonitrile-butadiene copolymer (Nippol-34, supplied by Nippon Zeon Co., Ltd.), 20 g of an epoxy resin (YD-017, supplied by Kukdo Chemical Co., Ltd.), and 100 g of a modified epoxy resin (Epikotel 180S70, supplied by Japan Jer) were dissolved in 600 g of a solvent, methylethylketone. Then, 1.2 g of a curing agent, 4- aminophenylsulfone, 0.5 g of metaphenylenediamine, 10 g of a filler, silica particles (Aerosil 200, supplied by Daegussa-Hils), and 0.1 g of an antioxidant, ethylene bis(oxyethylene)bis-2(2-(5-tertiary-butyl-4-hydroxy-m-toryl)-propionate) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer.

Example 2 100 g of an acrylonitrile-butadiene copolymer (Nippol-23, supplied by Nippon Zeon Co., Ltd.), 10 g of an epoxy resin (YDF-175, supplied by Kukdo Chemical Co., Ltd.), and 100 g of a modified epoxy resin (YDPN-636, supplied by Kukdo Chemical Co., Ltd.) were dissolved in 600 g of a solvent, methylethylketone. Then, 2.0 g of a curing agent, methane diamine, 10 g of a filler, silica particles (Aerosil 200, supplied by Daegussa-Hils), and 0.2 g of an antioxidant, octadecyl-3-(3,5-di-tertiary-butyl-4-hydroxyρhenyl)- propionate were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer. Example 3 100 g of an acrylonitrile-butadiene-acrylic acid terpolymer (ANM), 10 g of an epoxy resin (YD-012, supplied by Kukdo Chemical Co., Ltd.), and 150 g of a modified epoxy resin (KDCN-527, supplied by Kukdo Chemical Co., Ltd.) were dissolved in 500 g of a solvent, methylethylketone. Then, 0.1 g of a curing agent, isophorone diamine (IPDA), 0.9 g of diamino diphenyl sulfone (DDS), 10 g of a filler, silica particles (Aerosil 200, supplied by Daegussa-Hils), and 0.1 g of an antioxidant, N,N'-hexane-l,6-diylbis(3,5-di- tertiary-butyl-4-hydroxyphenyl propionamide) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer.

Comparative Example 1 150 g of a methylmethacrylate-2 and 150 g of an ethylhexylacrylate copolymer (supplied by Daeryung Chemical) containing hydroxyl groups and having a weight average molecular weight of 200,000 was dissolved in 500 g of a solvent, methylethylketone. Then, 1.5 g of a curing agent, isocyanate and 10 g of silica particles (Aerosil 200, supplied by Daegussa-Hils) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer. Comparative Example 2 200 g of a silicon resin (supplied by ShinEtSu Co., Ltd.) having a weight average molecular weight of 300,000 was dissolved in 500 g of a solvent, methylethylketone. Then, 0.5 g of a platinum catalyst, 1.2 g of a curing agent resin, and 10 g of silica particles (Aerosil 200, supplied by Daegussa-Hils) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer.

Comparative Example 3 100 g of an acrylonitrile-butadiene copolymer (Nippol-23, supplied by Nippon Zeon Co., Ltd.) and 100 g of an epoxy resin (YD-012, supplied by Kukdo Chemical Co., Ltd.) were dissolved in 400 g of a solvent, methylethylketone. Then, 1.5 g of a curing agent, N-aminoethyl piperazine (N-AEP) and 10 g of a filler, silica particles (Aerosil 200, supplied by Daegussa-Hils) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer.

Comparative Example 4 100 g of an acrylonitrile-butadiene copolymer (Nippol-34, supplied by Nippon Zeon Co., Ltd.) and 300 g of a modified epoxy resin (KDCN-529, supplied by Kukdo Chemical Co., Ltd.) were dissolved in 500 g of a solvent, methylethylketone. Then, 1.2 g of a curing agent, dimethyl aminomethyl phenol (DMP-10) and 10 g of a filler, silica particles (Aerosil 200, supplied by Daegussa-Hils) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer.

Comparative Example 5 100 g of an acrylonitrile-butadiene copolymer (Nippol-23, supplied by Nippon Zeon Co., Ltd.), 100 g of an epoxy resin (YD-012, supplied by Kukdo Chemical Co., Ltd.) and 100 g of a modified epoxy resin (KDCN-527, supplied by Kukdo Chemical Co., Ltd.) were dissolved in 450 g of a solvent, methylethylketone. Then, 2.3 g of a curing agent, tris-(dimethylaminomethyl)phenol (DMP-30) and 10 g of a filler, silica particles (Aerosil 200, supplied by Daegussa-Hils) were added to the mixture solution. The resulting mixture solution was stirred at 90 °C for one hour and kept at the room temperature for 3 hours. The resulting solution was coated on the one side of a polyimide film (Apical NPI, supplied by Kanekafuchi Co., Ltd.) with a comma knife and semi-cured at 150 °C for 10 minutes to manufacture an adhesive tape with a 20μm-thickness adhesive layer. The adhesive tapes prepared in the Examples and the Comparative Examples were analyzed in regard to thermal shrinkage, lead-shift test, outgasing, resin-molding and inspection as follows. The results are presented in Table 1. Measurement of Properties

(1) Thermal Shrinkage The thermal shrinkage was measured according to the JIS C-2318 measurement method. More specifically, each adhesive tape was cut in sample size of 1 cm 15 cm and marked in a length of 10 c m. After being kept in a hot-air oven at 150 °C for 30 minutes, the adhesive tape was measured in regard to length variation LI with a vernier calipers. The thermal shrinkage was then calculated according to the following equation. Thermal Shrinkage (%) - (10 - Ll)/10 x 100

(2) Lead-shift Test To measure the shift of a lead or a short circuit resulting from the lead shift as caused by the thermal shrinkage of the tape in the course of the high-temperature mounting process after the taping process, the adhesive tape was taped on a lead frame at 150 °C with a taping machine (supplied by Possehl Co., Ltd.), and the lead frame was kept in an oven at 200 °C for one hour. Then, the transfer of the lead tip was measured at 12 positions as marked in FIG. 2 with 200 magnefication of a Hi-scope compact vision system (model: KH-2200) and averaged. The figure of the shift of the lead is shown in FIG. 3.

(3) Outgas Test 5 g of the adhesive tape was kept in a hot-air oven at 150 °C for 40 minutes and then transferred to a desiccator at the room temperature for 10 minutes to cool down the sample. The weight of the sample (Wl) was measured to determine the weight difference, which was defined as a outgas rate. The outgas rate was calculated according to the following equation. Outgas Rate (%) = (5 - Wl)/5 x 100

(4) Resin-molding and Inspection In the same manner of the lead shift test, the lead frame taped with the adhesive tape was molded with a resin using an injection mold machine with STARCOM (Cheil Industries Inc.) with an injection pressure of 8 MPa and a holding pressure of 7.5 MPa at a barrel temperature of 217 °C and a mold temperature of 60 °C. After 20-resin sealing, cracks were detected by visual inspection.

Table 1

As can be seen from Table 1, when compared with the adhesive tapes prepared from the conventional adhesive compositions, the adhesive tapes prepared by coating the adhesive compositions of the present invention are more excellent in thermal shrinkage and outgas rate and have less defectives after resin molding. In particular, the lead shift test in which the shift distance of the lead is measured after the high-temperature taping process shows that the adhesive tapes of the present invention have an average lead shift distance remarkably smaller than those of the adhesive tapes prepared according to the Conventional Examples. Industrial Applicability As described above, the adhesive tape prepared by coating the one side or both sides of a substrate film with an adhesive composition including an acrylonitrile-butadiene copolymer or an acrylonitrile-butadiene-acrylic acid terpolymer containing carboxyl groups, an epoxy resin, a modified epoxy resin, a curing agent, an antioxidant, a filler, and other additives has a high reliability because of its excellencies in thermal shrinkage and outgas rate.

Claims

What is claimed is:

1. In an adhesive tape, which has an adhesive layer formed from an adhesive composition coated on the one side or both sides of a substrate film, the adhesive tape having a thermal shrinkage of 0.01 to 0.15 % as defined by a method stated in the Detailed Description of the Present Invention, and an outgas rate of 0.1 to 1.3 % as defined by a method stated in the Detailed Description of the Present Invention.

2. The adhesive tape as claimed in claim 1, wherein the substrate film includes at least one selected from polyethyleneterephthalate (PET) film, polypropylene (PP) film, polystyrene (PS) film, polycarbonate (PC) film, polymethylmethacrylate (PMMA) film, polyethylenenaphthalate film, polyetherimide (PEI) film, polyphenylenesulfide (PPS) film, polyimide (PI) film, polyetherketone (PEK) film, polyetheretherketone (PEEK) film, epoxy resin-glass fabric, or epoxy resin-polyimide- glass fabric.

3. The adhesive tape as claimed in claim 1, wherein the adhesive composition comprises of an acrylonitrile-butadiene copolymer or an acrylonitrile- butadiene-acrylic acid terpolymer containing carboxyl groups, an epoxy resin, a modified epoxy resin, a curing agent, an antioxidant, a filler, and other additives

4. The adhesive tape as claimed in claim 3, wherein the copolymer or the terpolymer has a weight average molecular weight of 20,000 to 1,000,000.

5. The adhesive tape as claimed in claim 3, wherein the epoxy resin includes at least one selected from bisphenol A type epoxy, or bisphenol F type epoxy.

6. The adhesive tape as claimed in claim 3, wherein the modified epoxy resin mcludes at least one selected from tetrabromophthalic anhydride epoxy resin, phenoxy resin, phenol-novolak epoxy resin, cresol-novolak epoxy resin, rubber-modified epoxy resin, or hydrogenated bisphenol A type epoxy resin.

7. The adhesive tape as claimed in claim 3, wherein the adhesive composition comprises: 1 to 15 parts by weight of the epoxy resin, and 1 to 200 parts by weight of the modified epoxy resin, with respect to 100 parts by weight of the copolymer or the terpolymer; 0.01 to 100 parts by weight of the curing agent, with respect to 100 parts by weight of the epoxy resin and the modified epoxy resin; 0.01 to 30 parts by weight of the antioxidant, with respect to 100 parts by weight of the copolymer or the terpolymer, the epoxy resin and the modified epoxy resin, and the curing agent; and 0.01 to 15 parts by weight of the filler, with respect to 100 parts by weight of the copolymer or the terpolymer, the epoxy resin and the modified epoxy resin, and the curing agent.

8. The adhesive tape as claimed in claim 3, wherein the curing agent includes at least one selected from acid anhydrides, amine-based curing agents, or acid- based curing agents.

9. The adhesive tape as claimed in claim 3, wherein the filler has a particle size of 0.5 to 5 μm, the filler including at least one selected from calcium carbonate, zinc oxide, silica, alumina, diamond powder, quartz powder, or zircon powder.