KR100302212B1 - Method for the preparation of the adhesive tape for the electronic parts - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive tape for electronic components having heat resistance used for bonding between components around a lead frame constituting a semiconductor device such as a lead, a die pad, and a heat sink semiconductor chip. In order to improve the electrical characteristics, etc.

The present invention is an acrylonitrile-butadiene copolymer having a weight average molecular weight of 5,000 to 200,000 and an acrylonitrile content of 5 to 50% by weight, a mixed epoxy resin of bisphenol A-based epoxy and cresol novolac epoxy or phenol novolac epoxy, one minute Adhesive layer by coating and drying on one or both sides of the heat resistant film using an adhesive composition composed of a compound containing two or more maleimide groups, an aromatic diamine compound, a liquid silicone resin, a filler made of inorganic or organic particles, and a solvent. The present invention relates to a method for producing an adhesive tape, wherein the adhesive tape thus prepared is excellent in general properties such as adhesive strength and heat resistance, and is particularly useful when used as an electronic component such as a semiconductor chip.

Description

Manufacturing method of adhesive tape for electronic component {METHOD FOR THE PREPARATION OF THE ADHESIVE TAPE FOR THE ELECTRONIC PARTS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive tape for electronic components that can be used for bonding between components around a lead frame constituting a semiconductor device such as a lead, a die pad, and a heat sink semiconductor chip.

Adhesive tapes used in conventional resin packaged semiconductor devices include adhesive tapes for fixing lead frames, adhesive tapes for heat sinks, TAB carrier tapes, and the like. In the case of adhesive tapes for fixing lead frames, the lead frame is fixed by It is used to improve the yield and productivity of the lead frame itself and the entire semiconductor assembly process, and is generally bonded onto the lead frame in the lead frame maker, and the semiconductor assembly company uses the semiconductor chip to mount the semiconductor chip and then package it with resin. At this time, the adhesive tape for fixing the lead frame should be excellent in general reliability at the semiconductor level, workability at the time of taping, adhesive strength after taping, etc., as well as sufficient heat resistance to withstand the heating in the assembly process of the semiconductor device.

Existing adhesive tapes used in such applications are, for example, coated with polyacrylonitrile, polyacrylate, or acrylonitrile-butadiene copolymer alone or the like on a heat resistant support film such as a polyimide film. Or those coated with a mixture of thermosetting resins were used. However, in recent years, the structure of the package has become complicated due to the requirement for multi-pinning or securing heat dissipation even inside the semiconductor device, and the demand for electrical, physical, thermal characteristics, and handling characteristics of organic materials of adhesive tapes has become strict. As a matter of fact, in the case of the conventional adhesive tape as described above, thermal properties, dimensional stability, and electrical properties are not sufficient, and in particular, in the process of bonding the heat sink and the lead fins or bonding the semiconductor chip and the lead fins with insulating tape. It has a problem of deforming or damaging metal materials such as lead frames.

In order to solve this problem, USP 5,494,757, USP 5,500,294 uses an adhesive composed of a butadiene-acrylonitrile copolymer having a piperazinyl ethylaminocarbonyl group, a compound containing two or more maleimide groups, a diamine-containing polysiloxane compound, and the like. In this case, there are problems such as adhesion and curing at a relatively low temperature, excellent heat resistance and electrical properties, but a large amount of outgas.

The present invention has been made to solve the above problems, and because it can be bonded and cured at a relatively low temperature, excellent heat resistance, electrical properties and less outgassing to provide an adhesive tape particularly useful for bonding between semiconductor components. The purpose is.

According to the present invention, an acrylonitrile-butadiene copolymer (component a) bisphenol having a weight average molecular weight in the range of 5,000 to 200,000 on one side or both sides of the heat resistant film, having an acrylonitrile content of 5-50% by weight, and containing a carboxyl group in the molecular chain Epoxy mixture resin (component b) of A type epoxy and cresol novolac epoxy or bisphenol A type epoxy and phenol novolac epoxy, the compound (component c) which contains two or more maleimide groups in one molecule, and aromatic diamine type compound (component d) Manufacture of adhesive tape for electronic parts, characterized by coating and drying an adhesive composition composed of a liquid silicone resin (component e) having an epoxy group, a filler (component f) composed of particles of an inorganic or organic component, and a solvent. It is about a method.

Hereinafter, the present invention will be described in detail.

In the present invention, the acrylonitrile-butadiene copolymer (component a) has a weight average molecular weight of 5,000 to 200,000, an acrylonitrile content of 5 to 50% by weight, and an equivalent of a carboxyl group in the range of 500 to 10,000 is used. At this time, when the weight average molecular weight is less than 5,000, the thermal stability is poor, the adhesion and heat resistance is lowered, and when the weight average molecular weight is greater than 200,000, the solubility in the solvent is worsened and the viscosity increases during solution preparation, resulting in poor workability. When the acrylonitrile content is less than 5% by weight, the heat resistance and chemical resistance are lowered, and when the acrylonitrile content is more than 50% by weight, the adhesion is poor. In addition, when the carboxyl group equivalent is greater than 10,000, the adhesion and heat resistance are lowered, and when the carboxyl equivalent is less than 500, the stability in the solution state is lowered, resulting in poor workability.

In the case of component b (epoxy mixture resin), 20 to 500 parts by weight of bisphenol A epoxy (more preferably 80 to 200 parts by weight), cresol novolac epoxy or phenol novolac epoxy 10 based on 100 parts by weight of component a An epoxy mixed resin composed of ˜200 parts by weight (more preferably 40-100 parts by weight) is used. In this case, when less than 20 weight part of bisphenol A epoxy is used, adhesive force falls, and when used excessively, heat resistance falls. In addition, when the cresol novolac epoxy or phenol novolac epoxy is less than 10 parts by weight, the heat resistance is poor, and when used excessively, the adhesive strength is lowered.

Component c is a compound containing two or more maleimide groups in one molecule, such as the compound represented by the following Chemical Formula 1 or Chemical Formula 2, and its amount is preferably 10 to 200 parts by weight based on 100 parts by weight of component a. If less than the weight part, the heat resistance and the post-curing elastic modulus and mechanical strength are lowered, and if excessive, the adhesive force is lowered.

In the case of component d (aromatic diamine-based compound), a suitable amount should be included with respect to the epoxy resin and bismaleimide resin content, and it is used in the range of 1 to 100 parts by weight based on 100 parts by weight of the total amount of component b and component c. In case of lack or excessive, solvent resistance, heat resistance, electrical resistance, etc. are lowered. In the present invention, it is particularly preferable to use an aromatic diamine compound having excellent electrical properties, heat resistance, and chemical resistance, and a curing accelerator may be used to promote a curing reaction.

In the case of component e (a silicone resin having an epoxy group), a silicone component, etc., chemically bonds in the adhesive, thereby improving heat resistance, water absorption, and electrical insulation of the adhesive, thereby providing durability and reliability of the adhesive tape. b It is added in the range of 0.1 to 20 parts by weight based on 100 parts by weight. At this time, when the addition of less than 0.1 parts by weight, such a performance improvement is insignificant, and when more than 20 parts by weight is added, the adhesive strength is lowered.

In the case of component f (particles of inorganic or organic components), it is preferable to add 1 to 50 parts by weight with respect to 100 parts by weight of component a. However, when less than 0.1 part by weight, adhesiveness is excessive and workability is lowered. The mechanical strength and elastic modulus are lowered, and when added in excess of 50 parts by weight, the adhesive strength is lowered. At this time, inorganic fillers that can be used include zinc oxide, silica, alumina and zircon powders, and organic fillers include powdery acrylic resins, polyamide resins, or silicon.

The adhesive composition prepared in the above composition is dissolved in a solvent so as to have a viscosity of 100 to 2000 cps (preferably 300 to 1000 cps).

In the present invention, the adhesive composition is applied so that the thickness after drying on the heat-resistant film is 10 ~ 50㎛ and dried for 1 to 20 minutes at 80 ~ 120 ℃ and attach the release film and the radius for 5 to 30 minutes at 80 ~ 120 ℃ The desired heat-resistant adhesive tape is obtained through a general adhesive tape manufacturing process.

At this time, as the heat-resistant film that can be used, for example, a heat-resistant resin film such as polyimide, polyphenylene sulfide, polyethylene terephthalate, polyethylene naphthalate, and the like can be used, the thickness is approximately 5 ~ 100㎛ (more Preferably 25-150 micrometers) is suitable.

On the other hand, as a peelable film which can be used by this invention, a polypropylene film, a fluororesin-type film, a polyethylene film, a polyethylene terephthalate film, a paper, and the film which provided them with silicone resin in some cases, etc. are mentioned.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

<Example 1>

100 parts by weight of an acrylonitrile-butadiene copolymer having a weight average molecular weight of 20,000, a carboxyl equivalent of 1,200 and an acrylonitrile content of 40% by weight was dissolved in methyl ethyl ketone to prepare a solution having a solid content of 15% by weight. 100 parts by weight of epoxy (epoxy equivalent 400), 50 parts by weight of cresol novolac epoxy (epoxy equivalent 200), 25 parts by weight of N ', N'-(4-4'-diphenylmethane) bismaleimide, diaminodiphenyl 25 parts by weight of methane, 2 parts by weight of liquid silicone resin having an epoxy group, and 6 parts by weight of zinc oxide having an average particle size of 2.0 µm were added and mixed, and the viscosity of the solution was adjusted to 800 to 1000 cps using methyl ethyl ketone and toluene solvent.

Using this adhesive composition, it was applied on a polyimide film having a thickness of 50 µm (trade name: KAPTON, manufactured by DUPON Co., Ltd.) so as to have a thickness of 20 µm after drying, and dried at 120 ° C. for 5 minutes, and then 38 µm thick polyethylene terephthalate. The film was laminated to prepare an adhesive tape.

<Example 2>

200 parts by weight of bisphenol A-based epoxy (epoxy equivalent 400) to 100 parts by weight of an acrylonitrile-butadiene copolymer having a weight average molecular weight of 100,000, a carboxyl equivalent of 2,700 and an acrylonitrile content of 27% by weight, and cresol novolac epoxy (epoxy Equivalent 200) 100 parts by weight, 50 parts by weight of N ', N'-(4-4'-diphenylmethane) bismaleimide, 50 parts by weight of diaminodiphenylmethane, 2 parts by weight of liquid silicone resin with epoxy group, average 6 parts by weight of zinc oxide having a particle size of 2.0 μm was added to adjust the viscosity of the solution to 800 to 1000 cps using methyl ethyl ketone and toluene solvent as in Example 1, and then the same method as in Example 1 using this adhesive composition. An adhesive tape was prepared.

<Example 3>

200 parts by weight of bisphenol A epoxy (epoxy equivalent 400) to 100 parts by weight of an acrylonitrile-butadiene copolymer having a weight average molecular weight of 100,000, a carboxyl equivalent of 2,300 and an acrylonitrile content of 32% by weight, and phenol novolac epoxy (epoxy Equivalent 200) 100 parts by weight, 50 parts by weight of N, N '-(4,4'-diphenylmethane) bismaleimide, 50 parts by weight of diaminodiphenylmethane, 2 parts by weight of liquid silicone resin with epoxy group, average particle 6 parts by weight of zinc oxide having a size of 2.0 μm was added to adjust the viscosity of the solution to 800 to 1000 cps using methyl ethyl ketone and toluene solvent as in Example 1, and then using the adhesive composition in the same manner as in Example 1 Adhesive tape was prepared.

Comparative Example 1

100 parts by weight of an acrylonitrile-butadiene copolymer having a weight average molecular weight of 100,000, a carboxyl equivalent of 2,300 and an acrylonitrile content of 32% by weight, 300 parts by weight of bisphenol A epoxy (400 equivalents), diaminodiphenylmethane 50 By weight, 2 parts by weight of a liquid silicone resin having an epoxy group, and 6 parts by weight of zinc oxide having an average particle size of 2.0 µm were added, and the viscosity of the solution was adjusted to 800 to 1000 cps using methyl ethyl ketone and toluene solvent as in Example 1. Next, an adhesive tape was prepared in the same manner as in Example 1 using this adhesive composition.

Comparative Example 2

100 parts by weight of an acrylonitrile-butadiene copolymer having a weight average molecular weight of 150,000 and an acrylonitrile content of 32% by weight, 200 parts by weight of bisphenol A epoxy (400 equivalents), 100 parts by weight of cresol novolac epoxy (200 equivalents) 1 part by adding 50 parts by weight of N, N '-(4-4'-diphenylmethane) bismaleimide, 50 parts by weight of diaminodiphenylmethane, and 6 parts by weight of zinc oxide having an average particle size of 2.0 µm. As described above, the viscosity of the solution was adjusted to 800 to 1000 cps using methyl ethyl ketone and toluene solvent, and then the adhesive tape was prepared in the same manner as in Example 1 using this adhesive composition.

Properties of the adhesive tapes prepared in Examples and Comparative Examples were evaluated by the following method and the results are shown in Table 1 below.

Adhesion

The copper foil was placed on a hot plate maintained at 150 ° C., and the tapes prepared in Examples and Comparative Examples were pressed for 5 seconds at a pressure of 5 kg / cm 2, and then cured for 1 hour in a 175 ° C. hot air oven, followed by tensile strength. T-PEEL strength was measured using a tester.

Pyrolysis temperature

The temperature at which the mass was reduced by 5% as measured using TGA (Dupont V4.IC 2200) was used as the pyrolysis temperature.

Outgas

After storage for 1 hour at 170 ℃ in the dryer the weight change was measured.

Moisture absorption

The weight change was measured after soaking in water at 23 ° C. for 24 hours.

Modulus

After curing at 170 ° C. for an additional 1 hour at 250 ° C., the elastic modulus was measured using a tensile strength tester.

Evaluation item Adhesion Pyrolysis temperature Outgas Moisture absorption Modulus unit (g / cm) (℃) (%) (%) (Kg / mm2) Example 1 900 370 0.7 1.5 4,500 Example 2 740 395 0.6 1.3 4,570 Example 3 720 395 0.7 1.3 4,990 Comparative Example 1 930 370 1.1 1.4 3,200 Comparative Example 2 310 390 0.6 1.2 4,660

In the analysis of the examples and comparative examples, the overall physical properties such as adhesion and heat resistance are excellent in the examples prepared according to the present invention, while in the case of the comparative examples, for example, especially in the case of Comparative Example 1 It has a disadvantage of high gas generation and low modulus of elasticity, and in Comparative Example 2, the adhesive strength is particularly bad. Thus, the adhesive tape prepared according to the present invention is very useful when used for electronic parts such as semiconductor devices because of excellent physical properties such as adhesion, heat resistance and electrical properties.

Claims (7)

Selected from carboxyl group-containing acrylonitrile-butadiene copolymers having a weight average molecular weight of 5,000 to 10,000 and acrylonitrile content of 5 to 50% by weight, bisphenol A epoxy and cresol novolac epoxy or bisphenol A epoxy and phenol novolac epoxy An epoxy composite resin, a compound containing two or more maleimide groups in one molecule, an aromatic diamine-based compound, a liquid silicone resin having an epoxy group, a filler and a solvent are prepared by coating and drying one or both sides of the heat resistant film. Method for manufacturing an adhesive tape for electronic components, characterized in The method of claim 1, wherein the carboxyl group-containing acrylonitrile-butadiene copolymer has a carboxyl group equivalent in the range of 500 to 10,000. The bisphenol A epoxy is used in an amount of 20 to 50 parts by weight based on 100 parts by weight of the acrylonitrile-butadiene copolymer, and 10 to 200 parts by weight of cresol novolac epoxy or phenol novolac epoxy. Manufacturing method of adhesive tape for electronic parts The method for producing an adhesive tape for electronic component according to claim 1, wherein the compound containing two or more maleimide groups in one molecule is used in an amount of 10 to 200 parts by weight based on 100 parts by weight of the acrylonitrile-butadiene copolymer. The method for manufacturing an adhesive tape for an electronic component according to claim 1 or 4, wherein the compound containing two or more maleimide groups in one molecule is selected from the compounds represented by the following Chemical Formulas (1) and (2). <Formula 1> <Formula 2> The method for producing an adhesive tape for electronic parts according to claim 1, wherein the aromatic diamine compound is used in an amount of 1 to 100 parts by weight based on 100 parts by weight of the total amount of the compound containing an epoxy mixed resin and two or more maleimide groups. The method for producing an adhesive tape for an electronic component according to claim 1, wherein the liquid silicone resin having an epoxy group is used in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the acrylonitrile-butadiene copolymer.