JPH108001A - Tacky adhesive tape and its application - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a tacky adhesive tape, having a tacky adhesive layer formed of an energy ray-hardening tacky component, an epoxy resin and a phenolic resin, capable of giving a cured article having high shock resistance, excellent in balance between a shear strength and a peel strength and useful for a silicone wafer, etc. SOLUTION: This tacky adhesive tape has a tacky adhesive layer which is formed of (A) an energy ray (e.g. ultraviolet rays)-hardening tacky component such as an acrylic compound, (B) an epoxy resin made of bisphenol, etc., and (C) a phenolic resin, and preferably contains (D) a heat activation-type latent epoxy resin hardening agent and/or an epoxy resin hardening accelerator. Further, the component C is compounded with the component B at a ratio of epoxy group to phenolic hydroxyl group of 0.2-4. Furthermore, it is preferable that an IC-chip is pasted on the tacky adhesive layer of the tacky adhesive tape, the layer is irradiated with energy rays for fixing the IC-chip on the tacky adhesive layer. Subsequently, the IC-chip is loaded on a lead frame through the tacky adhesive layer, and then heated to adhere the IC-chip to the lead frame.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel adhesive tape and a method for using the same. More specifically, the present invention provides
In particular, the present invention relates to a pressure-sensitive adhesive tape which is particularly suitable for use in a process of dicing a silicon wafer or the like and further performing die bonding to a lead frame and a method of using the same.

[0002]

BACKGROUND OF THE INVENTION Semiconductor wafers of silicon, gallium arsenide and the like are manufactured in a large-diameter state, and this wafer is cut and separated (diced) into element pieces (IC chips) and then subjected to the next step of a mounting step. Has been moved. At this time, the dicing, cleaning, drying, expanding, and pick-up steps are added to the semiconductor wafer in a state in which the semiconductor wafer is attached to the adhesive sheet in advance, and the semiconductor wafer is transferred to the next die bonding step.

[0003] Such an adhesive sheet used in the steps from the dicing step to the pick-up step of a semiconductor wafer has a sufficient adhesive force to the wafer chip from the dicing step to the drying step, and the wafer is picked up during the pick-up. It is desired that the chip has such an adhesive strength that an adhesive does not adhere to the chip.

[0004] In a die bonding step, the picked-up chip is bonded to a lead frame via a die bonding adhesive such as an epoxy bonding agent to manufacture a semiconductor device. However, when the chip is very small, it is difficult to apply an appropriate amount of adhesive, and the adhesive may protrude from the IC chip, or the IC may not be applied.
If the C chip is large, the amount of adhesive will be insufficient.
There has been a problem that bonding cannot be performed so as to have a sufficient bonding strength. In addition, such an operation of applying the die-bonding adhesive is complicated, and improvement is required to simplify the process.

In order to solve such a problem, various pressure-sensitive adhesive sheets for attaching a wafer having both a wafer fixing function and a die bonding function have been proposed (for example, Japanese Patent Application Laid-Open No. 2-32181).

JP-A-2-32181 discloses a composition comprising a (meth) acrylate copolymer, an epoxy resin, a photopolymerizable low-molecular compound, a heat-active latent epoxy resin curing agent and a photopolymerization initiator. An adhesive tape comprising an adhesive layer formed from a product and a substrate is disclosed. The adhesive layer has a function of fixing the wafer at the time of wafer dicing, and after the dicing is completed, is hardened by irradiating with an energy ray, and the adhesive strength between the substrate and the base material is reduced. Therefore, when the chip is picked up, the adhesive layer peels off together with the chip. I with adhesive layer
When the C chip is placed on the lead frame and heated, the adhesive layer develops an adhesive force, and the bonding between the IC chip and the lead frame is completed.

[0007] The pressure-sensitive adhesive sheet for attaching a wafer disclosed in the above-mentioned publication enables so-called direct die bonding, and the step of applying a die bonding adhesive can be omitted.

[0008] By the way, the adhesive layer of the above-mentioned adhesive tape has a very strong adhesion between the chip and the lead frame after die bonding after energy beam curing and heat curing. Further, improvement in toughness and impact resistance is required.

Further, in the semiconductor industry, two types of materials are used as materials for lead frames: iron-nickel alloys (FeNi alloys) and copper alloys. Among them, Fe
Ni alloys have been used as materials having good adhesiveness and thermal dimensional stability. However, with the recent improvement in productivity and higher integration, lead frames made of copper-based alloys that can quickly radiate high heat are becoming mainstream. The copper alloy is Fe
It is more cost-effective than Ni alloy. However, this copper-based alloy lead frame is inferior in the aforementioned adhesiveness and thermal dimensional stability because of its good thermal conductivity, resulting in increased chip warpage and the occurrence of package cracks due to poor adhesion and adhesion. There is a problem with reliability.

[0010] In addition, with the advancement of functions and integration of devices,
The semiconductor itself has also become highly integrated and sophisticated, and the number of pins, the size of chips, and the power consumption have been increasing. On the other hand, packaging has also been required to have higher mounting density and higher functionality. Conventionally, silver paste used for bonding a semiconductor chip and a lead frame cannot provide sufficient adhesiveness, and thus cannot meet such requirements for small size, thinness, and surface mounting. For this reason, there is a demand for an adhesive composition that is excellent in balance between shear strength and peel strength, replacing silver paste.

As a pressure-sensitive adhesive tape provided with an adhesive having an excellent balance between shear strength and peel strength, the present inventors have already disclosed in Japanese Patent Application No. 7-45648.
There has been proposed a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed of (A) an energy ray-curable adhesive component, (B) a thermosetting adhesive component, and (C) a flexible component. Although this adhesive tape is effective in solving the above-mentioned technical problems, improvement and improvement are constantly required in the semiconductor industry, which is a state-of-the-art technical field that is constantly evolving. In particular, an adhesive for die bonding incorporated in a semiconductor package as a final product is required to maintain sufficient adhesive properties even under severe heat and humidity conditions (for example, 85 ° C., 85% RH, one week), Improvements are being considered.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and has energy ray curability and heat curability, and can be used as a dicing tape in dicing. It can be used as an adhesive when mounting, and can finally give a cured product with high impact resistance, and has an excellent balance between shear strength and peel strength, severe heat and humidity conditions It is an object of the present invention to provide a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer capable of maintaining sufficient adhesive properties even below, and a method of using the same.

[0013]

SUMMARY OF THE INVENTION An adhesive tape according to the present invention comprises (A) an energy ray-curable adhesive component, (B) an epoxy resin,
(C) It is characterized by having an adhesive layer formed of a phenolic resin.

In the present invention, the phenolic resin (C) may be contained in the adhesive layer in a ratio of an epoxy group to a phenolic hydroxyl group (epoxy group / phenolic resin) with respect to the epoxy resin (B). (Hydroxyl group) in a ratio of 0.2 to 4.

The adhesive layer preferably further contains (D) a heat-active latent epoxy resin curing agent and / or an epoxy resin curing accelerator. The method for using the pressure-sensitive adhesive tape according to the present invention is as follows: an IC chip is attached to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape, and the IC chip is fixed to the pressure-sensitive adhesive layer by irradiating an energy ray. Placing the IC chip on a lead frame via the adhesive layer,
Then, by heating, the adhesive force is exerted on the adhesive layer to adhere the IC chip to the lead frame.

The energy beam to be irradiated is preferably an ultraviolet ray.

[0017]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the pressure-sensitive adhesive tape according to the present invention and a method for using the same will be described in detail.

The adhesive layer of the adhesive tape according to the present invention comprises:
(A) An energy ray-curable pressure-sensitive adhesive component, (B) an epoxy resin, and (C) a phenolic resin are essential components, and if necessary, (D) a heat-active latent epoxy resin curing agent and / or epoxy A resin curing accelerator is included.

(A) The energy ray-curable pressure-sensitive adhesive component has a sufficient adhesive strength before being irradiated with an energy ray such as an ultraviolet ray or an electron beam. Refers to components that disappear. Various such energy ray-curable pressure-sensitive adhesive components are known, and various conventionally known energy ray-curable pressure-sensitive adhesive components can be used without any particular limitation in the present invention. Examples of such an energy ray-curable pressure-sensitive adhesive component include (A-1) an acrylic pressure-sensitive adhesive, (A-2) an energy ray-polymerizable compound and, if necessary, (A-3) a photopolymerization initiator. Compositions can be given.

The acrylic pressure-sensitive adhesive (A-1) includes, for example, a (meth) acrylate copolymer comprising a structural unit derived from a (meth) acrylate monomer and a (meth) acrylic acid derivative. Can be Here, as the (meth) acrylate monomer, the alkyl group preferably has 1 to 18 carbon atoms (meth)
Alkyl acrylates such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate and the like are used. Examples of the (meth) acrylic acid derivative include (meth) acrylic acid, glycidyl (meth) acrylate, hydroxyethyl (meth) acrylate, and the like.

(Meth) acrylic acid derivative (Meth)
When glycidyl acrylate is used, the content of the component unit derived from glycidyl (meth) acrylate in the copolymer is usually 0 to 80 mol%, preferably 5 to 80 mol%.
50 mol%. By introducing a glycidyl group, compatibility with an epoxy resin as a thermosetting adhesive component described later is improved, and Tg after curing is increased, and heat resistance is also improved. The content of the component unit derived from (meth) acrylic acid is usually 0 to 40 mol%, preferably 5 to 2 mol%.
0 mol%. Further, by introducing a hydroxyl group-containing monomer such as hydroxyethyl acrylate, it becomes easy to control the adhesion to the adherend and the adhesive properties.

The molecular weight of the acrylic pressure-sensitive adhesive (A-1) is preferably 100,000 or more, and particularly preferably 150 or more.
000 to 1,000,000. The glass transition temperature of the acrylic pressure-sensitive adhesive is usually 20 ° C. or lower, preferably −7 ° C.
It is about 0 to 0 ° C. and has tackiness at normal temperature (23 ° C.).

The energy ray polymerizable compound (A-2) is a compound which polymerizes and cures when irradiated with energy rays such as ultraviolet rays and electron beams. This compound has at least one polymerizable double bond in the molecule and usually has a molecular weight of 100
３０30,000, preferably about 300 to 10,000. As such an energy ray-polymerizable compound (A-2), for example, low molecular weight compounds as disclosed in JP-A-60-196,956 and JP-A-60-223,139 are widely used. Used, specifically, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1,4-butylene glycol diacrylate, 1, Acrylate compounds such as 6-hexanediol diacrylate, polyethylene glycol diacrylate, and commercially available oligoester acrylate are used.

Further, polyester-type or polyether-type urethane acrylate oligomers, polyester acrylates, polyether acrylates, epoxy-modified acrylates and the like can be used.

The adhesive composition comprising the above components (A-1) and (A-2) is cured by irradiation with energy rays. As the energy beam, specifically, an ultraviolet ray, an electron beam, or the like is used.

When an ultraviolet ray is used as the energy ray, the polymerization curing time and the amount of light irradiation can be reduced by mixing the photopolymerization initiator (A-3) into the above composition.

As such a photopolymerization initiator (A-3),
Specifically, benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, benzoin dimethyl ketal, 2,4-diethylthioxanthone, α -Hydroxycyclohexyl phenyl ketone, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, β
-Chloranthraquinone and the like.

The energy ray-curable pressure-sensitive adhesive component (A) used in the present invention preferably comprises the above components (A-1) to (A-3), and the mixing ratio is appropriately set according to the characteristics of each component. However, generally, with respect to 100 parts by weight of the component (A-1),
Component (A-2) is 50 to 150 parts by weight, preferably 80 to 1 part by weight.
About 25 parts by weight, component (A-3) is 1.5 to 4.5 parts by weight,
Preferably, it is used in a ratio of about 2.4 to 3.8 parts by weight.

The energy ray-curable pressure-sensitive adhesive component (A) is usually 15 to 100 parts by weight, preferably 18 to 100 parts by weight, based on 100 parts by weight of the following epoxy resin (B).
It is used in an amount of 70 parts by weight, particularly preferably 20 to 50 parts by weight.

The epoxy resin (B) is not cured by energy rays, but becomes three-dimensional when heated.
It has the property of firmly bonding an adherend. As such an epoxy resin (B), conventionally known various epoxy resins are used, and usually, the molecular weight is 300 to 200.
Those having a molecular weight of about 0 are preferable, and particularly those having a molecular weight of 300 to 500
Preferably a normal liquid epoxy resin having a molecular weight of 330 to 400 and a molecular weight of 400 to 2500, preferably 500 to 20
It is desirable to use the resin in a form blended with a normal solid epoxy resin of No. 00. The epoxy equivalent of the epoxy resin preferably used in the present invention is usually 50 to 500.
0 g / eq. Specific examples of such an epoxy resin include glycidyl ethers of phenols such as bisphenol A, bisphenol F, resorcinol, phenyl novolak and cresol novolac; glycidyl ethers of alcohols such as butanediol, polyethylene glycol and polypropylene glycol; Glycidyl ethers of carboxylic acids such as phthalic acid, isophthalic acid and tetrahydrophthalic acid; glycidyl-type or alkyl glycidyl-type epoxy resins in which active hydrogen bonded to a nitrogen atom such as aniline isocyanurate is substituted with a glycidyl group; vinylcyclohexane diepoxide; 3,4-
Epoxycyclohexylmethyl-3,4-dicyclohexanecarboxylate, 2- (3,4-epoxy) cyclohexyl-
Examples of so-called alicyclic epoxides in which epoxy is introduced by, for example, oxidizing a carbon-carbon double bond in the molecule, such as 5,5-spiro (3,4-epoxy) cyclohexane-m-dioxane be able to.

Among these, in the present invention, bisphenol-based glycidyl type epoxy resin, o-cresol novolak type epoxy resin and phenol novolak type epoxy resin are preferably used.

These epoxy resins can be used alone or in combination of two or more. As the phenolic resin (C), a condensate of a phenol and an aldehyde such as alkylphenol, polyhydric phenol, biphenol, and naphthol is used without any particular limitation. The phenolic hydroxyl group contained in the phenolic resin (C) easily reacts with the epoxy group of the epoxy resin (B) by heating to form a cured product having high impact resistance. The adhesive obtained by using the energy ray-curable pressure-sensitive adhesive component (A), the epoxy resin (B) and the phenolic resin (C) together has a balance between shear strength and peel strength after curing. It is excellent and can maintain sufficient adhesive properties even under severe heat and humidity conditions.

For this reason, the adhesive tape according to the present invention having the adhesive layer formed from the components (A) to (C) is particularly preferably used as a tape for processing semiconductors. Examples of the phenolic resin (C) preferably used in the present invention include phenol novolak resin, o-cresol novolak resin, p-cresol novolak resin, t-butylphenol novolak resin, and dicyclopentadiene cresol resin. , Polyparavinylphenol resin, bisphenol A type novolak resin, or a modified product thereof.

The phenolic resin (C) has a ratio of an epoxy group to a phenolic hydroxyl group (epoxy group / phenolic hydroxyl group) based on the epoxy resin (B).
However, preferably 0.2 to 4, more preferably 0.5 to
It is used at a ratio of 1.5, particularly preferably 0.7 to 1.2. If the compounding ratio is out of this range, unreacted epoxy resin or phenol resin remains after heat curing, and the shear strength or peel strength after hot and humid conditions may be insufficient.

Next, the component (D) used as necessary in the present invention, ie, a heat-activated latent epoxy resin curing agent (hereinafter abbreviated as D1) and an epoxy curing accelerator (hereinafter abbreviated as D2). Will be described.

A heat-activated latent epoxy resin curing agent (D
1) is a type of curing agent that does not react with the epoxy resin at room temperature, is activated by heating at a certain temperature or higher, and reacts with the epoxy resin.

A heat-active latent epoxy resin curing agent (D
The activation method of 1) is a method in which active species (anions and cations) are generated by a chemical reaction by heating; it is dispersed in the epoxy resin (B-1) stably at around room temperature, There is a method of dissolving and dissolving to initiate a curing reaction; a method of eluting at a high temperature with a molecular sieve sealing type curing agent to initiate a curing reaction; a method using microcapsules, and the like.

Specific examples of the thermally active latent epoxy resin curing agent (D1) used in the present invention include various onium salts, dibasic acid dihydrazide compounds, dicyandiamide, amine adduct curing agents, and high melting points such as imidazole compounds. Active hydrogen compounds and the like can be mentioned.

These heat-active latent epoxy resin curing agents can be used alone or in combination of two or more. The heat-active latent epoxy resin curing agent (D1) as described above is preferably 0.1 to 20 parts by weight, more preferably 0.2 to 10 parts by weight, based on 100 parts by weight of the epoxy resin (B). And particularly preferably 0.3 to 5
Used in parts by weight.

As the epoxy resin curing accelerator (D2), for example, a complex in which an atom such as Ti, Al, or Zr is bonded to an alkoxy group, a phenoxy group, an acyloxy group, a β-diketonato group, an o-carbonylphenolate group, or the like. Compounds.

Among the above complex compounds, the most preferred is an organoaluminum compound. Specific examples thereof include, for example, trismethoxyaluminum, trisethoxyaluminum, trisisopropoxyaluminum, trisphenoxyaluminum, trisparamethylphenoxyaluminum, isopropoxydiethoxyaluminum, trisbutoxyaluminum, trisacetoxyaluminum, trisstearatoaluminum,
Aluminum trisbutyrate, aluminum trispropionate, aluminum trisisopropionate, aluminum trisacetylacetonato, aluminum tristrifluoroacetylacetonato, aluminum trishexafluoroacetylacetonato, aluminum trisethylacetoacetate, aluminum trissalicylaldehyde, Tris diethylmalolato aluminum, trispropyl acetoacetato aluminum, tris butyl acetoacetato aluminum, tris dipivaloyl methanato aluminum, diacetylacetonato dipivaloyl methanato aluminum, bis (ethylacetoacetato) (acetylacetonato) Aluminum, diisopropoxy (ethylacetoacetato) aluminum, and the like.

These complex compounds can be used alone or in combination of two or more. The epoxy resin curing accelerator (D2) as described above is preferably used in an amount of 0.1 to 10 with respect to 100 parts by weight of the epoxy resin (B).
Parts by weight, more preferably 0.2 to 8 parts by weight, particularly preferably 0.3 to 5 parts by weight.

The adhesive layer of the adhesive tape of the present invention comprises (A) the energy ray-curable adhesive component as described above and (B)
The curing reaction can be performed under mild conditions by using the epoxy resin and the phenolic resin (C) as essential components, and further adding the component (D) as necessary.

The adhesive layer composed of each of the above components has energy ray curability and heat curability, and can be used as an adhesive for fixing a wafer during dicing.
At the time of mounting, it can be used as an adhesive for bonding the chip and the lead frame. And finally it can give a cured product with high impact resistance through thermal curing, and also has excellent balance between shear strength and peel strength,
Sufficient adhesive properties can be maintained even under severe hot and humid conditions.

The adhesive layer of the adhesive tape of the present invention may contain the following various additives in addition to the above-mentioned components. For example, the adhesive layer further includes, for the purpose of imparting conductivity after die bonding, gold, silver, copper, nickel, aluminum, stainless steel, carbon, or ceramic, or nickel,
A conductive filler such as aluminum or the like coated with silver may be added, and for the purpose of imparting thermal conductivity, metal materials such as gold, silver, copper, nickel, aluminum, stainless steel, silicon, and germanium may be used. A thermally conductive material such as an alloy thereof may be added.

Furthermore, the adhesive layer of the adhesive tape of the present invention is provided with a flexibility after curing, which is disclosed in Japanese Patent Application No. Hei.
A flexible component described in No. 45648 may be added.
The flexible component is uniformly dispersed in the cured adhesive, improving the brittleness of the adhesive layer, and having resistance to external stress.

Further, in order to improve the adhesiveness / adhesiveness to the adherend after curing, the adhesive layer is coated on the adhesive layer as disclosed in Japanese Patent Application No. 7-2.
No. 56090 may be added. The coupling agent is considered to have an organic functional group that reacts with the epoxy resin (B), and can improve adhesiveness and adhesion without impairing the heat resistance of the cured product, and also has a high water resistance (moisture and heat resistance). improves.

As the coupling agent, a silane type (silane coupling agent) is preferable from the viewpoint of its versatility and cost advantages. Further, in the adhesive layer, in order to adjust the initial adhesive force and cohesive force before irradiation with energy rays,
Organic polyvalent isocyanate compounds, organic polyvalent imine compounds, and the like can also be added.

The organic polyvalent isocyanate compound includes an aromatic polyvalent isocyanate compound, an aliphatic polyvalent isocyanate compound, an alicyclic polyvalent isocyanate compound, and a trimer of these polyvalent isocyanate compounds. And urethane prepolymers having terminal isocyanate obtained by reacting these polyvalent isocyanate compounds with polyol compounds. More specific examples of the organic polyvalent isocyanate compound include, for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate Notate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4 ' -Diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate and the like.

Specific examples of the organic polyvalent imine compound include N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate. , Tetramethylolmethane-
Tri-β-aziridinyl propionate, N, N'-toluene-
2,4-bis (1-aziridinecarboxamide) triethylenemelamine and the like can be mentioned.

Further, a compound which is colored by irradiation with energy rays can be contained in the above-mentioned adhesive layer. By such energy ray irradiation, by including a compound to be colored in the adhesive layer, after the adhesive tape is irradiated with energy rays, the tape is colored,
Therefore, the detection accuracy when detecting the wafer chip by the optical sensor is enhanced, and no malfunction occurs when the wafer chip is picked up. Further, there is obtained an effect that whether or not the adhesive tape has been irradiated with the energy ray can be immediately visually determined.

Further, an expanding agent can be added to the above-mentioned adhesive layer. By adding the expanding agent, the expansion after the polymerization and curing of the adhesive layer is further facilitated.

Further, an antistatic agent can be added to the above-mentioned adhesive layer. By adding an antistatic agent, static electricity generated at the time of expansion or at the time of pickup can be suppressed, so that the reliability of the chip is improved.

The pressure-sensitive adhesive tape of the present invention has a pressure-sensitive adhesive layer composed of the above-mentioned components. Without using
It may be a thin film of a composition comprising the above components, or may have a multilayer structure comprising an adhesive layer formed on a support using the above composition.

As the support of the adhesive sheet of the present invention,
For example, when using ultraviolet rays as energy rays,
Polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene -Transparent films such as (meth) acrylic acid copolymer film, ethylene / (meth) acrylic acid ester copolymer film, polystyrene film and polycarbonate film are used. Further, these crosslinked films are also used. Furthermore, these laminated films may be used. When an electron beam is used as the energy beam, it is not necessary to be transparent. Therefore, in addition to the above-mentioned transparent films, an opaque film, a fluororesin film, or the like obtained by coloring them can be used.

The surface tension of the support is preferably 4
0 dyne / cm or less, more preferably 37 dyne / cm or less,
Particularly preferably, it is desirably 35 dyne / cm or less. Such a support having a low surface tension can be obtained by appropriately selecting the material, or can be obtained by applying a silicone resin or the like to the surface of the support and subjecting it to a release treatment. .

The thickness of such a support is usually from 10 to
It is about 300 μm, preferably about 20 to 200 μm, particularly preferably about 50 to 150 μm. Further, in the present invention,
Abrasive grains may be dispersed in the support. By including the abrasive grains in the support, even if the cutting blade cuts into the support and an adhesive adheres to the cutting blade, clogging can be easily removed by the polishing effect of the abrasive grains.

The pressure-sensitive adhesive tape according to the present invention is obtained by coating a pressure-sensitive adhesive composition comprising the above components on a release sheet according to a generally known method such as a comma coater, a gravure coater, a die coater, or a reverse coater. , Dried to form an adhesive layer, and the release sheet is removed. When the above-mentioned support is used, a pressure-sensitive adhesive tape is produced by applying a pressure-sensitive adhesive composition on the support in the same manner and drying to form a pressure-sensitive adhesive layer. can do. The above-mentioned adhesive composition can be applied by dissolving or dispersing it in a solvent, if necessary.

The thickness of the adhesive layer thus formed is usually 3 to 100 μm, preferably 10 to 60 μm.
m is desirable. The adhesive tape obtained as described above is used as follows.

After sticking the adhesive tape of the present invention on one surface of the silicon wafer, the silicon wafer and the adhesive tape are cut using a cutting means such as a dicing saw to form an IC chip. obtain. At this time, the adhesive force between the silicon wafer and the adhesive tape is usually 50 to 2000 g / 25 m.
m, preferably 100 to 1500 g / 25 mm, while the adhesive force between the adhesive layer of the adhesive tape and the support is usually 500 g / 25 mm or less.

Next, the adhesive tape adhered to the IC chip obtained as described above is irradiated with energy rays. Energy rays that can be used in the present invention include ultraviolet rays (center wavelength = about 365 nm), electron beams, and the like. When using ultraviolet rays as energy rays, the illuminance is usually set in the range of 20 to 500 mW / cm ² , and the irradiation time is set in the range of 0.1 to 150 seconds. Also, for example, when irradiating an electron beam, various conditions can be set according to the above-described case of irradiating an ultraviolet ray. In addition, it is also possible to perform auxiliary heating during energy beam irradiation as described above.

By irradiating the energy ray in this manner, the energy ray-curable adhesive component (A) is cured, and the adhesive force between the silicon wafer and the adhesive layer is usually 50
~ 4000g / 25mm, preferably 100 ~ 3000g /
Increase to 25mm. On the other hand, the adhesive strength between the adhesive layer of the adhesive tape and the support is usually 1 to 500 g / 25 mm, preferably 100 g / 25 mm or less.

Therefore, by irradiating with the energy beam as described above, the adhesive layer can be fixed and left on one side of the IC chip and can be peeled off from the support. Note that the energy irradiation may be performed before the dicing step.

The IC chip to which the adhesive layer is fixed in this way is placed on a lead frame, and then heated to cure the epoxy resin in the adhesive layer, and
The chip and the lead frame are bonded. The heating temperature in this case is usually about 100 to 300 ° C., preferably about 150 to 250 ° C., and the heating time is usually 1 to 30 ° C.
１２０120 minutes, preferably 5-60 minutes. By such heating, the thermosetting adhesive component is cured, and the IC chip and the lead frame can be firmly bonded.

The finally cured adhesive layer has high heat resistance, and the cured product has an excellent balance without one of shear strength and peel strength being extremely low.
Has high impact resistance. Further, even under severe hot and humid conditions, sufficient adhesive properties can be maintained.

[0066]

According to the present invention, it has energy ray curability and heat curability, can be used as a dicing tape at the time of dicing, and can be used as an adhesive at the time of mounting. A possible adhesive tape is provided. Further, according to the present invention, there is provided a method of using such an adhesive tape.

[0067]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

In the following Examples and Comparative Examples, "shear strength" and "peel strength" were evaluated as follows. Adhesive tape is attached to the back surface of a silicon wafer with a shear strength of 350 μm and a thickness of 2000 mm, and after irradiation with ultraviolet rays, 4 mm × 4 mm
And the silicon chip with the adhesive layer was adhered to a copper plate having a thickness of 30 mm × 30 mm and a thickness of 300 μm and cured under the curing conditions described in Table 1 to obtain a sample. .

Using a horizontal load measuring device (manufactured by Aiko Engineering Co., Ltd.), the shear adhesive strength of the sample (kg / 4 mm × 4 m
m) was measured. During the measurement, the sample was held on a hot plate at 250 ° C. for 30 seconds, and the measurement was performed at a load speed of 12 mm / min as it was. Adhesive tape is applied to the back surface of a silicon wafer with a peel strength of 350 μm and polished at # 2000, and after irradiation with ultraviolet rays, 5 mm × 10
Dicing to mm, picking up with adhesive layer,
The obtained silicon chip with an adhesive layer was adhered to a copper plate having a thickness of 150 μm and cured under the curing conditions shown in Table 1 to obtain a sample.

The silicon chip side of this sample was bonded and fixed, and the bonding strength (g / 5 mm) when the copper plate was peeled off by 90 ° peel was measured. In addition, the peeling speed was unified to 10 mm / min.

A sample prepared in the same manner as above was left under hot and humid conditions of 85 ° C. and 85% RH for 168 hours, and then the adhesive strength was measured in the same manner as above. In the following examples, the following were used as (A) an energy ray-curable adhesive component, (B) an epoxy resin, and (C) a phenolic resin. (A) 55 parts by weight of butyl acrylate, 10 parts by weight of methyl methacrylate, 20 parts by weight of glycidyl methacrylate, and 15 parts by weight of 2-hydroxyethyl acrylate as an energy ray-curable adhesive component (meth) acrylate copolymer. Weight average molecular weight 900,000, glass transition temperature -28
A mixture of 100 parts by weight of a copolymer at 100C, 100 parts by weight of dipentaerythritol hexaacrylate as an energy ray-polymerizable compound, and 3 parts by weight of 1-hydroxycyclohexyl phenyl ketone as a photopolymerization initiator. (B) Epoxy resin acrylic rubber fine particles (flexible component) dispersed liquid bisphenol F type resin (epoxy equivalent: 205 to 215) 62
A mixture of parts by weight, 17 parts by weight of a solid bisphenol A type resin (epoxy equivalent: 800 to 900), and 21 parts by weight of an o-cresol novolak type resin (epoxy equivalent: 215 to 225).

The epoxy equivalent of the mixed epoxy resin was 310 to 330, and the content of the flexible component in the mixture was 12.5% by weight. (C) phenolic resin phenol novolak (hydroxyl equivalent 118) (D) heat-active latent epoxy resin curing agent and / or
Is a curing accelerator D-1-1: 2-phenyl-4,5-dihydroxymethylimidazole D-1-2: dicyandiamide D-2: trisacetylacetonatoaluminum (E) aromatic polyvalent isocyanate

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Example 1 The components were mixed at the ratios shown in Table 1 to obtain an adhesive composition having a ratio of epoxy groups to phenolic hydroxyl groups of 0.92. This adhesive composition is coated with a plasticized polyvinyl chloride layer and an ethylene / methacrylic acid copolymer layer on a side of an ethylene / methacrylic acid copolymer layer (surface tension 35 dyn / cm ² ) and dried to obtain an adhesive tape.

Using the obtained adhesive tape, "shear strength" and "peel strength" were evaluated as described above.
Table 1 shows the results.

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Examples 2 to 4 and Comparative Examples 1 to 4 The same operation as in Example 1 was performed except that the mixing ratio of each component was changed as shown in Table 1. The results are shown in Tables 1 and 2.

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[Table 1]

Continued on the front page (51) Int.Cl. ⁶ Identification number Reference number in the agency FI Technical indication location C09J 7/02 JKE C09J 7/02 JKE H01L 21/52 H01L 21/52 E 21/301 21/78 M

Claims (5)

[Claims] (A) an energy ray-curable pressure-sensitive adhesive component;
An adhesive tape having an adhesive layer formed of (B) an epoxy resin and (C) a phenolic resin. 2. The phenolic resin (C) has a ratio of an epoxy group to a phenolic hydroxyl group (epoxy group / phenolic hydroxyl group) of 0.2 to the epoxy resin (B).
The adhesive tape according to claim 1, wherein the adhesive tape is contained in the adhesive layer in a ratio of 接着 4. 3. The adhesive layer according to claim 1, wherein said adhesive layer further comprises (D) a heat-active latent epoxy resin curing agent and / or an epoxy resin curing accelerator.
3. The adhesive tape according to item 1. 4. An IC chip is attached to the adhesive layer of the adhesive tape according to claim 1, and the IC chip is fixed to the adhesive layer by irradiating an energy ray. After
The IC chip is mounted on a lead frame via the adhesive layer, and then heated to cause the adhesive layer to exhibit an adhesive force and bond the IC chip to the lead frame. How to use adhesive tape. 5. The method according to claim 4, wherein the energy beam to be irradiated is ultraviolet rays.