JPH05136260A - Wafer processing tape - Google Patents

Abstract

PURPOSE:To prevent development of mold on the surface of a susceptible adherend without adding an additives such as a mold preventing agent or the like by utilizing an acrylic resin emulsion adhesive agent mixing liquid which is obtained by mixing a particular surfactant having a strong sterilizing property and a particular water soluble organic compound. CONSTITUTION:A water processing tape can be obtained by coating the surface of a base film with an aclyric resin emulsion adhesive agent mixing liquid which has been obtained by adding a water soluble organic compound expressed by the equation (wherein R1 is a 1-4C carbon compound, R2 is H or CH3CO) to an aclyric resin emulsion adhesive agent obtained by copolimerization using a cationic surface active agent. As the cationic surface active agent, a quaternary ammonium salt is used and the amount of addition is set to 0.1 to 5.0 pts.wt. for the monomer of 100 pts.wt. Moreover, amount of addition of a water soluble organic compound is set to 1.0 to 20 pts.wt. for 100 pts.wt. of the aclyric resin emulsion adhesive agent. With multiple effect of the cationic surfactant and water soluble organic compound, mold on the surface of adherend can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer processing tape used in a semiconductor IC manufacturing process.

[0002]

2. Description of the Related Art Semiconductor integrated circuit (IC) chips are usually
It is manufactured by a method of slicing a high-purity silicon single crystal or the like into a semiconductor wafer, and then incorporating an integrated circuit on the surface by means such as impurity thermal diffusion or ultrafine processing, and dicing into chips. In each of these steps, a method of attaching a wafer processing tape to the surface of the semiconductor wafer is used in order to prevent damage or damage to the surface pattern of the semiconductor wafer.

However, the time until the wafer processing tape is attached to the semiconductor wafer and the processing of the semiconductor wafer is completed and the wafer processing tape is peeled off is generally within one day. In many cases, the time until the wafer processing tape is peeled off exceeds one day due to the increase in the production amount, the increase in holidays, and the like. in this case,
The surface of the semiconductor wafer may be moldy or corroded. In particular, the aluminum surface is easily affected by the adhesive of the tape for wafer processing, which sometimes causes corrosion or mold.

As a wafer processing tape for preventing corrosion, Japanese Patent Publication No. 1-51511 discloses a water-based emulsion pressure-sensitive adhesive containing a nonionic surfactant alone on at least one side of a synthetic resin film, or a boiling point of 100 ° C. Disclosed is a film for an IC process, which is obtained by applying a water emulsion-based pressure-sensitive adhesive containing both the water-soluble organic compound and the nonionic surfactant.

However, since the film for IC process of the above publication is a water-emulsion type adhesive agent, it is apt to cause mold, and a mold which has been left for a long time, for example, 10 days or more, is subjected to a mold resistance by the method described in JIS Z 2911. There was a defect that mold was generated when the sex test was conducted.
Further, there is a drawback in that the antifungal agent bleeds to the surface of the adhesive and the surface of the semiconductor wafer is contaminated only by adding the antifungal agent to the adhesive.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wafer processing tape which does not cause mold even if the wafer processing tape is left on the surface of a semiconductor wafer for a long time.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in order to achieve the above object, and as a result, as a pressure-sensitive adhesive for acrylic resin emulsion, acrylic resin emulsion polymerized by using a cationic surfactant. We have found that a tape for wafer processing, which is obtained by applying a pressure-sensitive adhesive to a base film, prevents the generation of mold.
It was necessary to add a large amount of a cationic surfactant, and in that case, the surface of the semiconductor wafer was contaminated by the bleeding of the cationic surfactant, and the adhesive strength decreased with time.

Further, a wafer processing tape formed by coating a base film with an acrylic resin emulsion pressure sensitive adhesive compounding liquid obtained by adding a water-soluble organic compound such as ethylene glycol monoethyl ether to the acrylic resin emulsion pressure sensitive adhesive is mold. However, in order to prevent this, it is necessary to add a large amount of a water-soluble organic compound, in which case the surface of the semiconductor wafer is contaminated by bleeding of the water-soluble organic compound, The adhesive strength decreased with time.

Then, as a result of further intensive studies, an acrylic resin emulsion adhesive containing a water-soluble organic compound such as ethylene glycol monoethyl ether was added to an acrylic resin emulsion adhesive polymerized by using a cationic surfactant. By using the wafer processing tape coated with the agent mixture liquid, the addition amount can be reduced due to the synergistic effect of the cationic surfactant and the water-soluble organic compound, the generation of mold can be prevented, and the semiconductor wafer surface is contaminated. However, they found that the adhesive strength did not decrease with time, and completed the present invention.

That is, the present invention relates to an acrylic resin emulsion pressure-sensitive adhesive polymerized by using a cationic surfactant,
The following general formula (1) [Chemical formula 2]

[0011]

Embedded image R ₁ —O—CH ₂ —CH ₂ —O—R ₂ ... (1) (In the above formula, R ₁ is a carbon compound having 1 to 4 carbon atoms, and R ₂ is H.
Or CH ₃ CO. ) A tape for wafer processing, characterized in that the base film is coated with an acrylic resin emulsion pressure-sensitive adhesive compounding liquid added with a water-soluble organic compound.

Examples of the cationic surfactant used in the present invention include quaternary ammonium salts such as alkyltrimethylammonium bromide and alkyldimethylbenzylammonium bromide. Other cationic surfactants have problems such as weak emulsifying power and weak bactericidal power. As the anion of the quaternary ammonium salt, a quaternary ammonium salt having a bromine ion is particularly preferable.

The amount of the cationic surfactant added is preferably 0.1 to 5.0 parts by weight, more preferably 0.2 to 3.0 parts by weight, based on 100 parts by weight of the monomer. If the amount of the cationic surfactant is less than 0.1 part by weight, the effect of preventing the generation of mold will be weak, which is not preferable, and if it exceeds 5 parts by weight, the interface of the tape for wafer processing becomes unfavorable. The activator may bleed and contaminate the adherend, which is not preferable. Further, a nonionic surfactant may be added to increase the stability during polymerization.

Examples of the water-soluble organic compound used in the present invention include ethylene glycol monoethyl ether,
The following general formula (1) [Chemical Formula 3] such as ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether and ethylene glycol monomethyl ether

[0015]

Embedded image R ₁ —O—CH ₂ —CH ₂ —O—R ₂ ... (1) (In the above formula, R ₁ is a carbon compound having 1 to 4 carbon atoms, and R ₂ is H.
Or CH ₃ CO. ). The compound shown by these is mentioned.

The amount of the water-soluble organic compound added is usually 100 parts by weight of the acrylic resin emulsion adhesive.
1.0 to 20 parts by weight is preferable, and more preferably 5 to
10 parts by weight. If it is less than 1 part by weight, the effect of preventing mold is weak, and if it exceeds 20 parts by weight, the water-soluble organic compound may bleed and contaminate the adherend when formed into a tape for wafer processing. In addition, the adhesive strength decreases with time, which is not preferable.

The acrylic resin emulsion adhesive referred to in the present invention is, for example, a (meth) acrylic acid ester monomer such as methyl methacrylate, butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, etc. and a carboxylic acid-containing vinyl. Acrylic, methacrylic, crotonic, maleic, fumaric, itaconic acid, etc. which are surfactants, deionized water, and polymerization initiators are emulsion-polymerized in water. Can be appropriately performed according to the required adhesive strength. The acrylic resin emulsion pressure-sensitive adhesive thus polymerized usually contains a solid content (acrylic resin) of 30 to 60 wt%, but can be further diluted with water to adjust the viscosity at the time of application.

The water-soluble organic compound is usually added to the acrylic resin emulsion pressure-sensitive adhesive after polymerization of the pressure-sensitive adhesive or before application to the base film. Further, a crosslinking agent and a nonionic surfactant can be added to the acrylic resin emulsion pressure-sensitive adhesive as required.

As the base film used in the present invention, a film made of synthetic resin, natural, synthetic rubber or the like can be appropriately selected. As an example of the composition of the base film, ethylene-vinyl acetate copolymer, polybutadiene,
Soft vinyl chloride resin, polyolefin, polyester,
Thermoplastic elastomer such as polyamide, and synthetic rubber such as diene-based, nitrile-based, silicon-based, and acrylic-based rubber.

As a method for applying the acrylic resin emulsion pressure-sensitive adhesive compounding liquid to the substrate film, it is applied by a known coating method such as reverse roll coater, gravure coater, bar coater, die coater, comma coater, etc. It is possible by drying with hot air at 150 ° C. The coating thickness after drying is usually 1 μm to 100 μm.
It is about μm. In addition, it is preferable to attach a synthetic resin film called a separator on the pressure-sensitive adhesive layer side in order to protect the pressure-sensitive adhesive layer, if necessary.

[0021]

The present invention will be described more specifically with reference to the following examples.

Example 1 150 parts by weight of deionized water was placed in a flask equipped with a thermometer, a reflux condenser, a dropping funnel, a nitrogen inlet and a stirrer, and cetyltrimethylammonium bromide (cationic surfactant) 2 as a surfactant. 0.0 parts by weight was added and the temperature was raised to 70 ° C. under stirring in a nitrogen atmosphere, and then 0.5 parts by weight of ammonium persulfate (polymerization initiator) was added and dissolved. Then, 100 parts by weight of a monomer mixture consisting of 22.5 parts by weight of methyl methacrylate, 73.5 parts by weight of 2-ethylhexyl acrylate, 2 parts by weight of glycidyl methacrylate and 2 parts by weight of methacrylic acid were continuously added dropwise over 4 hours.
After completion of dropping, the mixture was continuously stirred for 3 hours to polymerize to give a solid content of about 47
A weight% acrylic resin emulsion adhesive was obtained.

With respect to 100 parts by weight of this adhesive, 5.0 parts by weight of ethylene glycol monoethyl ether as a water-soluble organic compound and tetramethylol-tri-as a crosslinking agent.
0.3 parts by weight of β-aziridinyl propionate was added to prepare a pressure sensitive adhesive formulation liquid. This compounded solution was applied by a roll coater to the corona-treated EVA surface of a 110-μm-thick film composed of two layers of EVA and PP formed by the T-die method, and dried at 90 ° C. to obtain an acrylic film with a coating thickness of 10 μm. A tape for wafer processing having a resin emulsion pressure-sensitive adhesive layer was obtained.

The wafer processing tape thus obtained was applied to a 4-inch semiconductor wafer and a 4-inch semiconductor wafer having aluminum vapor-deposited on its surface using an automatic tape applying machine ("ATM-1000B" manufactured by Takatori Corporation) for 1 day. And left for 10 days in the cassette case. Then, an automatic tape peeling machine ("ATRM-" manufactured by Takatori Co., Ltd.)
2000B ") to remove the tape for wafer processing,
The obtained 4-inch semiconductor wafer was 0.2 μm using a surface inspection device HLD-300B manufactured by Hitachi Electronics Engineering Co., Ltd.
The degree of contamination of the semiconductor wafer was measured depending on the number of foreign matter of m or more.

Further, aluminum was vapor-deposited on the surface 4
Using an inch semiconductor wafer, the presence or absence of mold was examined based on the mold resistance test of electrical equipment shown in JIS Z 2911-5. In addition, in order to measure the adhesive force of the wafer processing tape, the adhesive force to the mirror wafer was measured with a Tensilon type tensile tester (manufactured by Toyo Baldwin Co., Ltd.) immediately after being applied and after being left for 10 days. The results were good, as shown in [Table 1], with no generation of mold, no contamination of the semiconductor wafer, and almost no change in adhesive strength.

Example 2 0.5 part by weight of myristyltrimethylammonium bromide (cationic surfactant) was used as a surfactant for emulsion polymerization, and polyoxyethylene nonylphenyl ether (nonionic surfactant) 1.0
Acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Example 1 except that parts by weight was added to ethylene glycol monomethyl ether 10.0 as a water-soluble organic compound.
Parts by weight, 1.0 part by weight of polyglycol polyglycidyl ether as a cross-linking agent was applied to the corona-treated one side of a 100 μm-thick PP film formed by the T-die method with a roll coater. Then, it was dried at 100 ° C. to obtain a wafer processing tape having an acrylic resin emulsion pressure-sensitive adhesive layer with a coating thickness of 20 μm. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results were good as shown in [Table 1].

Example 3 An acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Example 2 was supplemented with 8.0 parts by weight of ethylene glycol monobutyl ether as a water-soluble organic compound and 0 parts of trimethylolpropane polyglycidyl ether as a crosslinking agent. .5
1 part by weight is added to prepare an adhesive compounding solution, which is formed into a film by the T-die method, and then coated on one side of a biaxially stretched PET film having a thickness of 50 μm, which has been subjected to corona treatment, with a roll coater.
After drying at 00 ° C., a wafer processing tape having an acrylic resin emulsion pressure-sensitive adhesive layer having a coating thickness of 40 μm was obtained. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results were good as shown in [Table 1].

Example 4 Cetyltrimethylammonium bromide (cationic surfactant) as a surfactant for emulsion polymerization
The acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Example 1 except that 0.1 part by weight and 1.5 parts by weight of polyoxyethylene nonyl phenyl ether (nonionic surfactant) were added, were mixed with a water-soluble organic compound. A corona of a PP film having a thickness of 100 μm formed by a T-die method from a pressure-sensitive adhesive compounding solution containing 0.8 part by weight of ethylene glycol monobutyl ether as a compound and 1.0 part by weight of polyglycol polyglycidyl ether as a cross-linking agent. The treated one side was coated with a roll coater and dried at 100 ° C. to obtain a wafer processing tape having an acrylic resin emulsion pressure-sensitive adhesive layer with a coating thickness of 20 μm. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The result is [Table 1]
Shown in.

Comparative Example 1 Polyoxyethylene nonylphenyl ether (nonionic surfactant) as a surfactant for emulsion polymerization
An acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Example 1 except that 1.5 parts by weight was added to 10.0 parts by weight of diethylene glycol monobutyl ether as a water-soluble organic compound and polyglycol polyglycidyl ether as a crosslinking agent. Was added to the corona-treated one side of a PP film having a thickness of 100 μm formed by the T-die method, by a roll coater,
After drying at 100 ° C., a wafer processing tape having an acrylic resin emulsion pressure-sensitive adhesive layer with a coating thickness of 20 μm was obtained. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results are shown in [Table 1].

Comparative Example 2 In an acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Example 1, 10.0 parts by weight of diethylene glycol monobutyl ether as a water-soluble organic compound and 1.0 part of polyglycol polyglycidyl ether as a cross-linking agent were used. The adhesive compounding liquid added by weight is applied by a roll coater to one side of a 100 μm-thick PP film formed by the T-die method and subjected to corona treatment, and dried at 100 ° C. to obtain an applied thickness of 2
A tape for wafer processing having a 0 μm acrylic resin emulsion adhesive layer was obtained. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results are shown in [Table 1].

Comparative Example 3 Acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Comparative Example 1 was supplemented with 10.0 parts by weight of ethylene glycol monobutyl ether as a water-soluble organic compound and polyglycol polyglycidyl ether as a cross-linking agent. A pressure-sensitive adhesive compounding liquid added with 0 parts by weight was formed into a film by the T-die method, and the thickness was 1
Coated on one side of a corona treated PP film of 00 μm with a roll coater and dried at 100 ° C. to obtain a coating thickness of 20.
A tape for wafer processing having a μm acrylic resin emulsion adhesive layer was obtained. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results are shown in [Table 1].

Comparative Example 4 In an acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Comparative Example 1, 10.0 parts by weight of diethylene glycol monobutyl ether as a water-soluble organic compound and 1.0 part by weight of polyglycol polyglycidyl ether as a crosslinking agent. Parts by weight Permachem Topside 400 as an antifungal agent
(Manufactured by Permachem Asia Co., Ltd.) A pressure-sensitive adhesive compounding liquid added with 0.1 part by weight was formed into a film by a T-die method to a thickness of 100 μm.
m PP film was coated on one side of the corona treated with a roll coater and dried at 100 ° C. to obtain a wafer processing tape having an acrylic resin emulsion adhesive layer with a coating thickness of 20 μm. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results are shown in [Table 1].

Comparative Example 5 An acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Comparative Example 1 was added with 40.0 parts by weight of ethylene glycol monobutyl ether as a water-soluble organic compound and polyglycol polyglycidyl ether 1.0 as a cross-linking agent. A pressure-sensitive adhesive compounding liquid containing 1 part by weight was formed into a film by the T-die method to a thickness of 1
Coated on one side of a corona treated PP film of 00 μm with a roll coater and dried at 100 ° C. to obtain a coating thickness of 20.
A tape for wafer processing having a μm acrylic resin emulsion adhesive layer was obtained. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results are shown in [Table 1].

Comparative Example 6 Cetyltrimethylammonium bromide (cationic surfactant) 1 as a surfactant for emulsion polymerization
Acrylic resin emulsion pressure-sensitive adhesive obtained in the same manner as in Example 1 except that 0.0 part by weight was added, and 10.0 parts by weight of diethylene glycol monobutyl ether as a water-soluble organic compound and polyglycol polyglycidyl ether as a crosslinking agent. The adhesive compounding liquid added with 1.0 part by weight was applied by a roll coater to one side of a 100 μm-thick PP film formed by the T-die method, which had been corona-treated,
After drying at 100 ° C., a wafer processing tape having an acrylic resin emulsion pressure-sensitive adhesive layer with a coating thickness of 20 μm was obtained. The tape for wafer processing thus obtained was evaluated in the same manner as in Example 1. The results are shown in [Table 1].

[0035]

[Table 1]

[0036]

EFFECT OF THE INVENTION The tape for wafer processing of the present invention is a fungicide by using an acrylic resin emulsion pressure-sensitive adhesive compounding liquid in which a specific surfactant having a strong sterilizing power and a specific water-soluble organic compound are used in combination. It is possible to prevent the generation of mold on the surface of the adherend, which is easily affected by aluminum or the like, without adding additives such as. Moreover, since no additives such as antifungal agents are added, the surface of the semiconductor wafer is not contaminated.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoko Takeuchi 2-1, Tangodori, Minami-ku, Aichi Prefecture Nagoya City Mitsui Toatsu Chemicals, Inc.

Claims (3)

[Claims] 1. An acrylic resin emulsion pressure-sensitive adhesive prepared by polymerizing using a cationic surfactant, wherein R ₁ —O—CH ₂ —CH ₂ —O— R ₂ ... (1) (In the above formula, R ₁ is a carbon compound having 1 to 4 carbon atoms, and R ₂ is H.
Or CH ₃ CO. ) A tape for wafer processing, characterized in that the base film is coated with an acrylic resin emulsion pressure-sensitive adhesive compounding liquid to which a water-soluble organic compound represented by (4) is added. 2. 100 parts by weight of an acrylic resin emulsion pressure-sensitive adhesive prepared by polymerizing an acrylic resin emulsion pressure-sensitive adhesive compounding liquid using 0.1 to 5.0 parts by weight of a cationic surfactant with respect to 100 parts by weight of a monomer. 2. The tape for wafer processing according to claim 1, wherein 1.0 to 20.0 parts by weight of a water-soluble organic compound is added to the tape. 3. The wafer processing tape according to claim 1, wherein the cationic surfactant is a quaternary ammonium salt having a bromine ion as an anion.