JPH05198542A - Grinding method for rear of semiconductor wafer and adhesive tape used in the method - Google Patents

Abstract

PURPOSE:To obtain adhesive tape which provide low adhesion in an early stage, and what is more, does not increase its adhesive power even if it is left over for long time after pasted by defining its early stage adhesive power with a mirror wafer within a specific range with the adhesive tape which uses a pressure sensitive adhesive which contains a specific surface activator and cross-link agent. CONSTITUTION:An acrylic group resin water emulsion type adhesive agent-compounding solution which includes a specific water-soluble organic compound, a specific interface activator and a specific cross-link agent is prepared. The compounding solution is coated and dried on the top of the base material film, which provides adhesive tape provided with a pressure sensitive agent layer whose adhesive power with a mirror wafer ranges from 50 to 450g/25mm. This construction makes it possible to obtain a reverse side grinding adhesive tape for semiconductor which provides strong early stage adhesion to a semiconductor mirror wafer and what is more, minimizes an increase in its adhesive power with the lapse of time. When the adhesive tape is applied to the surface of the semiconductor wafer to grind the reverse side of the semiconductor, this construction makes it possible to protect the semiconductor wafer from damage and separate the tape from the wafer with ease even if it is left over for about ten days and enhance workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor integrated circuit (hereinafter referred to as "semiconductor IC") chip manufacturing process, in which a surface of the semiconductor wafer on which the integrated circuit is incorporated (hereinafter referred to as "semiconductor wafer surface") is adhered. The present invention relates to a method of applying a tape and polishing the other surface of the semiconductor wafer (hereinafter referred to as the back surface of the semiconductor wafer), and an adhesive tape used in the method.

[0002]

2. Description of the Related Art Generally, a semiconductor IC chip is obtained by slicing a single crystal such as high-purity silicon into a semiconductor mirror wafer, and incorporating an integrated circuit on one surface of the semiconductor mirror wafer by means such as impurity thermal diffusion or ultrafine processing. After the formation, the back surface of the semiconductor wafer is ground to reduce the thickness, and then the semiconductor wafer is diced into chips.

Conventionally, when the back surface of a semiconductor wafer is ground, cracking of the semiconductor wafer itself due to grinding stress and damage to an integrated circuit formed on the surface of the semiconductor wafer (hereinafter referred to as damage to the semiconductor wafer) are prevented. Therefore, a method of sticking a protective adhesive tape on the surface of the semiconductor wafer is adopted.

As this adhesive tape, for example, Japanese Patent Publication No. 1
JP-A-51511 discloses an aqueous emulsion pressure-sensitive adhesive containing only a nonionic surfactant on at least one surface of a synthetic resin film, or a water-soluble organic compound having a boiling point of 100 ° C. or higher and a nonionic surfactant. Semiconductor I prepared by applying a water emulsion adhesive containing both of the agents
A C process film is disclosed.

The semiconductor IC process film can be easily removed by washing with water or the like even when the back surface of the semiconductor wafer is ground and peeled from the front surface of the semiconductor wafer, even if the adhesive residue, dust or the like adheres to the front surface. However, it is not always satisfactory because the peelability is difficult because the increase in adhesive strength over time is not suppressed.

Conventionally, the time until the adhesive tape is peeled off after adhering the adhesive tape on the front surface of the semiconductor wafer and grinding the back surface of the semiconductor wafer is at most one day. Due to the increase in quantity or holidays, the time until the adhesive tape is peeled off is 1
The number of days is increasing. Therefore, when an adhesive tape having an adhesive layer whose adhesive strength increases with time is used, there is a problem that peeling becomes difficult.

If an adhesive tape having an adhesive layer whose adhesive strength increases with time is attached to the front surface of a semiconductor wafer and the back surface of the semiconductor wafer is ground, the surface of the semiconductor wafer is left for a long time, for example, for one day or more. There is a problem that the adhesive strength to the adhesive tape increases, the adhesive tape becomes difficult to peel off, and the semiconductor wafer is damaged during the peeling. Even if the adhesive strength does not increase with time, the same problem occurs when the initial value of the adhesive strength is large.

As a method for improving the cohesive force of the adhesive,
For example, in JP-A-60-32873, 100 parts by weight of a solid content of an acrylic emulsion pressure-sensitive adhesive having a crosslinkable functional group, 0.1 to 10 parts by weight of a melamine resin as a crosslinking agent and aziridinyl are used. Compound 0.00
A pressure-sensitive adhesive composition containing 1 to 5 parts by weight is disclosed. The pressure-sensitive adhesive composition has a good balance between cohesive force and adhesive force and provides a pressure-sensitive adhesive layer having excellent temperature-sensitive properties at low and high temperatures.

However, the pressure-sensitive adhesive composition disclosed in this publication has a high adhesion value to the SUS-304 plate at 23 ° C. of as high as 570 to 700 g / 20 mm.

When the adhesive tape having such a high adhesive strength is attached to the front surface of the semiconductor wafer, the back surface of the semiconductor wafer is ground, and the adhesive tape is peeled from the front surface of the semiconductor wafer, the semiconductor wafer is damaged. There is. Therefore, the pressure-sensitive adhesive composition cannot be applied as an adhesive for an adhesive tape used when grinding a semiconductor wafer.

Further, according to the knowledge of the present inventors, the pressure-sensitive adhesive composition has a small temperature dependency of the adhesive strength and is good, but the adhesive strength after being adhered to an adherend increases with time. Has the drawback of being large.

Further, in JP-A-61-211387, [A] (a) (a) unsaturated acid monomer unit 0.5 to 10
% By weight (b) 0.5 to 10% by weight of a hydroxyl group-containing unsaturated monomer unit (c) 100 parts by weight of a vinyl-based copolymer, the balance of which is an unsaturated monomer unit copolymerizable with (a) and (b) (B) Emulsion 100 consisting of 0.2 to 10 parts by weight of epoxy resin, and 0.2 to 5 parts by weight of [B] alkali metal compound are disclosed. Has been done.

However, the re-peelable pressure-sensitive adhesive has an adhesive force to a SUS plate at 20 ° C. of 700 to 900 g / 25.
Since the value is as high as mm, the semiconductor wafer may be damaged when peeled from the surface of the semiconductor wafer, and cannot be applied as an adhesive for an adhesive tape used when grinding the semiconductor wafer.

[0014]

The first object of the present invention is to solve the above-mentioned problems and to provide a low initial adhesive strength when applied to the surface of a semiconductor wafer, and to adhere even if left for a long time after application. PROBLEM TO BE SOLVED: To provide an adhesive tape for backside grinding of a semiconductor wafer having an adhesive layer whose force does not increase with time, and secondly to attach the adhesive tape to the front surface of the semiconductor wafer and grind the backside of the semiconductor wafer. To provide.

[0015]

DISCLOSURE OF THE INVENTION The inventors of the present invention have diligently studied, and an appropriate adhesive force of an adhesive tape used for grinding the back surface of a semiconductor wafer varies depending on the surface state of the semiconductor wafer. It has been found that 50 to 450 g / 25 mm is optimum as the adhesive force to the mirror wafer before being incorporated.

That is, if the adhesive force immediately after applying the adhesive tape for grinding the back surface of the semiconductor wafer is less than 50 g / 25 mm, it may be peeled off when grinding the back surface of the semiconductor wafer, and it may not function sufficiently for protection. However, there is a drawback that the semiconductor wafer is damaged. Also, adhesive strength is 450g / 25mm
It has been found that if it exceeds the range, the peeling property is lowered and peeling becomes difficult, and if the peeling is forcibly performed, the semiconductor wafer will be damaged.

Furthermore, at least 5 days, preferably 1
As a result of diligent study on the pressure-sensitive adhesive composition such that the pressure-sensitive adhesive strength is kept in the range of 50 to 450 g / 25 mm even if left on the mirror wafer for 0 days, as a result, a nonionic surfactant, a specific water-soluble organic compound The present inventors have found that an acrylic resin water emulsion type pressure-sensitive adhesive containing a compound and a specific cross-linking agent has a low initial adhesive force and does not thicken with time, and has reached the present invention.

The exact reason why the pressure-sensitive adhesive used in the present invention has such a property is not clear, but since it contains a crosslinking agent, it has a high molecular weight and the cohesive force of the pressure-sensitive adhesive is increased.
By the synergistic effect of the surfactant and the cross-linking agent such as forming a barrier layer between the adhesive layer and the semiconductor wafer by the surfactant bleeding out on the surface of the adhesive layer,
It is presumed that this is because the initial value of the adhesive strength is lowered and the thickening with time is prevented.

That is, in the method for grinding the back surface of a semiconductor wafer according to the first aspect of the present invention, an acrylic resin water emulsion type is provided on one surface of a base film made of a synthetic resin film monolayer or multilayer. 100 parts by weight of adhesive as a solid content, nonionic surfactant 0.05 to
10 parts by weight, 0.01 to 10 parts by weight of a crosslinking agent selected from the group consisting of an epoxy crosslinking agent, an aziridine crosslinking agent, and a mixture of an epoxy crosslinking agent and an aziridine crosslinking agent, and a boiling point of 100 ° C or higher. Some water-soluble organic compound
A pressure-sensitive adhesive tape provided with a pressure-sensitive adhesive layer having an acrylic resin water emulsion-type pressure-sensitive adhesive coating solution containing 1 to 100 parts by weight, dried, and having an adhesive force to a mirror wafer at 23 ° C. of 50 to 450 g / 25 mm. Is provided on the surface of the semiconductor wafer on which the integrated circuit is incorporated and the back surface is ground, and a back surface grinding method for a semiconductor wafer is provided.

According to the second aspect of the present invention, 100 parts by weight of a solid content of an acrylic resin water emulsion type pressure-sensitive adhesive is provided on one side of a base film made of a monolayer or a multilayer of a synthetic resin film, Nonionic surfactant 0.0
5 to 10 parts by weight, 0.01 to 10 parts by weight of a crosslinking agent selected from the group consisting of an epoxy crosslinking agent, an aziridine crosslinking agent and a mixture of an epoxy crosslinking agent and an aziridine crosslinking agent, and a boiling point of 100 ° C. The acrylic resin water emulsion type pressure sensitive adhesive coating liquid containing 0.1 to 100 parts by weight of the above water-soluble organic compound is applied and dried, and 2
50-450g adhesion to mirror wafer at 3 ° C
There is provided a pressure-sensitive adhesive tape for backside grinding of a semiconductor wafer, which is / 25 mm.

In the present invention, the adhesive force to the mirror wafer at 23 ° C. is a value measured by the following method.

Using a rubber roller having a pressing force of 2 kg / cm ² , a sample tape having a width of 25 mm was attached to the surface of the silicon mirror wafer, and the sample tape was allowed to stand in an atmosphere of a temperature of 23 ° C. and a relative humidity of 50% for a predetermined time. Using a tensile tester (manufactured by Toyo Baldwin Co., Ltd.) at a temperature of 23
At a peeling angle of 180 ° and a peeling speed of 30 cm / min, the adhesive force when peeling the sample tape from the surface of the silicon mirror wafer is measured.

First, an adhesive tape for backside grinding of a semiconductor wafer according to the present invention will be described.

An adhesive tape for backside grinding of a semiconductor wafer according to the present invention comprises a base film made of a synthetic resin film having a single-layer structure or a multi-layer structure, and a specific amount of an acrylic resin water emulsion type pressure-sensitive adhesive, a specific amount. Nonionic surfactant,
A specific amount of the crosslinking agent selected from the group consisting of an epoxy-based crosslinking agent, an aziridine-based crosslinking agent, and a mixture of an epoxy-based crosslinking agent and an aziridine-based crosslinking agent, and a specific amount of the boiling point of 10
It is manufactured by applying an acrylic resin water emulsion type pressure-sensitive adhesive compounding liquid containing a water-soluble organic compound at 0 ° C. or higher and drying it to form a pressure-sensitive adhesive layer having a specific composition on one surface of the base film. It

The pressure-sensitive adhesive tape for grinding the back surface of a semiconductor wafer manufactured by the above-mentioned method is usually formed by applying a polypropylene film or the like as a release layer on the surface of the pressure-sensitive adhesive layer and then forming a roll-shaped roll or a predetermined shape. It is cut and made into a laminated body, or cut into a predetermined shape and then attached to a polypropylene film or the like to be stored and transported as a roll-shaped roll or the like.

As the base film used in the present invention, ethylene vinyl acetate copolymer (hereinafter referred to as EVA), polybutadiene (hereinafter referred to as PB), polyethylene, polypropylene (hereinafter referred to as PP), polyamide, polyethylene terephthalate, etc. are synthesized. A film having a thickness of 5 to 500 μm, which is composed of a single layered body of a resin film or a multi-layered body of these, can be mentioned.

Among these substrate films, the Shore D hardness is preferably 40 or less in order to absorb the stress when the back surface of the semiconductor wafer is ground and prevent the semiconductor wafer from being damaged. When the base film is a multilayer body,
It is preferable that the film on the side on which the pressure-sensitive adhesive layer is formed has a Shore D hardness of 40 or less.

Further, in order to improve the coatability of the pressure-sensitive adhesive coating liquid on the base film, it is preferable to subject the surface of the base film to corona discharge treatment in advance.

The acrylic resin emulsion pressure-sensitive adhesive used in the present invention comprises an acrylic acid alkyl ester monomer or a methacrylic acid alkyl ester monomer, and
It is obtained by emulsion polymerization of a monomer mixture containing a monomer having a carboxyl group in a deionized water medium containing an emulsifier, a polymerization initiator and the like. Further, a monomer mixture obtained by mixing a vinyl monomer or the like copolymerizable with them may be used if necessary. The selection of the monomer composition can be appropriately performed depending on the required adhesive force.

Usually, the resulting acrylic resin water emulsion type pressure sensitive adhesive coating liquid contains 30 to 60% by weight of solid content (acrylic resin). It can also be diluted with.

Examples of the acrylic acid alkyl ester monomer or methacrylic acid alkyl ester monomer include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl acrylate,
Hexyl methacrylate, octyl acrylate, octyl methacrylate, nonyl acrylate, nonyl methacrylate, dodecyl acrylate, dodecyl methacrylate and the like can be mentioned, and the alkyl group may be linear or branched. Further, two or more kinds of the above alkyl acrylate ester monomers or methacrylic acid alkyl ester monomers may be used in combination depending on the purpose.

Examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid,
Examples thereof include itaconic acid, maleic acid and fumaric acid.

The amount of the monomer having a carboxyl group used is 0.1 to 100 parts by weight of the monomer mixture constituting the acrylic resin water emulsion type adhesive.
It is preferably 10 parts by weight. The carboxyl group in the pressure-sensitive adhesive reacts with the crosslinking agent described below to form a cross-linked structure. Therefore, when the amount of the monomer having a carboxyl group in the pressure-sensitive adhesive is less than 0.1 part by weight, it is sufficient. A cross-linked structure is not formed, the cohesive force becomes insufficient, and it is impossible to prevent reduction in initial adhesive force and increase in viscosity over time.

If the amount of the monomer having a carboxyl group in the pressure-sensitive adhesive exceeds 10 parts by weight, the reaction system during emulsion polymerization becomes unstable and it becomes difficult to obtain a stable emulsion, which is not preferable.

Examples of the vinyl monomer copolymerizable with the acrylic acid alkyl ester monomer or the methacrylic acid alkyl ester monomer and the monomer having a carboxyl group include, for example, hydroxyethyl acrylate,
Examples thereof include hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, acrylamide, methacrylamide, dimethylamino acrylate, dimethylamino methacrylate, vinyl acetate, styrene and acrylonitrile.

A cross-linking agent for the acrylic resin water emulsion type pressure-sensitive adhesive, a nonionic surfactant and a boiling point of 10
The water-soluble organic compound having a temperature of 0 ° C. or higher is usually added after the pressure-sensitive adhesive is polymerized or before being applied to the base film, but the surfactant is added when the pressure-sensitive adhesive is emulsion-polymerized. It can also be added together with an emulsifier used for emulsification.

Examples of the nonionic surfactant used in the present invention include polyoxyethylene lauryl ether,
Polyoxyethylene alkyl ethers such as polyoxyethylene stearyl ether, polyoxyethylene lauryl ester, polyoxyethylene alkyl esters such as polyoxyethylene stearyl ester, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, etc. Oxyethylene alkyl phenyl ethers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate and other sorbitan alkyl esters, polyoxyethylene sorbitol laurate, polyoxyethylene sorbitol oleate laurate and other polyoxyethylene sorbitan alkyl esters , Polyoxyalkylenes such as polyoxyethylene polyoxypropylene,
Examples include polyoxyethylene alkyl amides and the like.

The amount of the nonionic surfactant added is 0.05 to 10 parts by weight, preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the solid content of the acrylic resin emulsion type adhesive.
Parts by weight. When the amount of the surfactant is less than 0.05 part by weight, the bleed-out of the surfactant on the surface of the pressure-sensitive adhesive layer is reduced, and the effect of lowering the adhesive strength is reduced. That is,
There is a drawback that the initial adhesive strength of the adhesive tape exceeds 450 g / 25 mm, which is not preferable. On the other hand, if the amount exceeds 10 parts by weight, the adhesive strength of the adhesive tape is extremely lowered, and the adhesive tape is peeled off when the back surface of the semiconductor wafer is ground, so that the protective effect cannot be sufficiently exerted, which is not preferable.

Examples of the water-soluble organic compound having a boiling point of 100 ° C. or higher used in the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol isopropyl ether and ethylene glycol monobutyl ether. Carbitol compounds such as cellosolve compounds, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monobutyl ether, glycosorb compounds such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether Ethyl ether acetate, diethylene glycol Acetate-based compounds such as butyl ether acetate, diethylene glycol, triethylene glycol, glycol compounds such as dipropylene glycol, and the like. Of these, the boiling point is 130
Water-soluble organic compounds having a temperature of 0 ° C. or higher are preferable.

The amount of the water-soluble organic compound added can be appropriately selected in consideration of the adhesive force to the semiconductor wafer to be used. Usually, the solid content of the acrylic resin water emulsion type adhesive is 100 parts by weight. On the other hand, 0.1-10
The amount is preferably 0 parts by weight, more preferably 1 to 50 parts by weight. If it is less than 0.1 part by weight, the coating property on the base film is poor, and if it exceeds 100 parts by weight, the adhesive strength becomes too low, which is not preferable.

As the epoxy-based crosslinking agent used in the present invention,
Examples thereof include water-soluble epoxy resins that can react with carboxylic acids such as sorbitol polyglycidyl ether, polyglycol polyglycidyl ether, pentaerythritol polyglycidyl ether, and trimethylolpropane polyglycidyl ether.

As the aziridine-based crosslinking agent used in the present invention, tetramethylol-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, trimethylolpropane-
Examples thereof include aziridine compounds capable of mutually reacting with a carboxylic acid such as tri-β- (2-methylaziridine) propionate.

The epoxy-based cross-linking agent and the aziridine-based cross-linking agent may be used alone, but it is preferable to use a mixture of the two in order to reduce the initial adhesive strength and prevent thickening over time. The mixing ratio of both is 0.1 to 10 parts by weight of the aziridine-based crosslinking agent with respect to 1 part by weight of the epoxy-based crosslinking agent.
In order to achieve the object of the present invention, it is preferable to use parts by weight.

Of these crosslinking agents, water-soluble ones are simple substances, and water-insoluble ones are dissolved in a small amount of alcohols or an organic solvent such as acetone and added to the acrylic resin water emulsion pressure-sensitive adhesive. ..

The amount of the crosslinking agent added is usually 100 parts by weight of the solid content of the acrylic resin water emulsion adhesive.
0.01 to 10 parts by weight, preferably 0.05 to 5
Parts by weight. The addition amount of the cross-linking agent can be appropriately selected within the above range depending on the kind of the cross-linking agent, the required adhesive strength and the like. When the amount of the cross-linking agent is less than 0.01 parts by weight, the cross-linking effect of the acrylic resin is small and the initial adhesive force of the adhesive tape on the mirror wafer exceeds 450 g / 25 mm.
This is not preferable because the adhesive strength increases with time. Also,
If it exceeds 10 parts by weight, crosslinking will proceed too much and the adhesive strength will be 50 g.
Since it is less than / 25 mm, it cannot adhere to the surface of the semiconductor wafer and cannot serve the purpose.

The method for applying the acrylic resin water emulsion type pressure-sensitive adhesive compounding solution to the base film is not particularly limited and a known method is applied. For example, a known coating method using a reverse roll coater, a gravure coater, a bar coater, a die coater, a comma coater, etc. is exemplified.

Usually, one surface of the substrate film, preferably the surface treated with corona discharge, is coated with the acrylic resin water emulsion type pressure sensitive adhesive composition of the above composition at room temperature or a temperature in the vicinity thereof by the above method, and then 80 The pressure-sensitive adhesive layer is formed by drying with hot air of 150 ° C. The thickness of the pressure-sensitive adhesive layer after drying is usually about 1 to 100 μm.

The adhesive tape for grinding the back surface of a semiconductor wafer of the present invention has a synthetic resin film such as a polypropylene film attached to the surface of the adhesive layer as a release layer (separator) to protect the adhesive layer as necessary. Preferably.

As the synthetic resin film used as the release layer, a polypropylene film having good release properties is preferably used. In particular, a biaxially stretched polypropylene film is preferably used because it has good peelability and workability such as sticking and peeling.

When using the adhesive tape, first, the release film is peeled from the surface of the adhesive layer, and then the adhesive tape is attached to the surface of the semiconductor silicon wafer, that is, the surface on which the integrated circuit is incorporated. Then, it is trimmed by machine or manually so as to match the shape of the semiconductor wafer.

Next, a method for adhering the adhesive tape for grinding the back surface of the semiconductor wafer of the present invention to the front surface of the semiconductor wafer and grinding the back surface of the semiconductor wafer will be described.

An integrated circuit is incorporated on the surface of the mirror wafer to form a semiconductor wafer, an adhesive tape is attached to the surface of the semiconductor wafer via an adhesive layer, and trimming is performed by a machine or manually to match the shape of the semiconductor wafer.

Then, the back surface of the semiconductor wafer to which the adhesive tape is attached is polished by a polishing machine (for example, manufactured by Disco Corporation,
Format: Infeed grinder DFG-821F / 8
Using a mold or the like) to reduce the thickness to about 100 to 600 μm.

At this time, it is preferable that the grindstone used has a grain size of # 100 to # 1000 in the first rough cutting and a grain size of # 700 to # 3000 in the final finishing.
The particle size is preferably 10 to 150 μm at the first rough cutting and 1 to 30 μm at the final finishing.

The peripheral speed of the grindstone is 2 to 10 μm / sec in the first rough cutting and 0.1 to 10 μm in the final finishing.
2 μm / sec is preferable. Considering productivity and the like, the polishing time is preferably 1 to 20 minutes.

At this time, the adhesive tape attached to the surface of the semiconductor wafer prevents damage to the semiconductor wafer and adhesion of polishing dust or the like to the integrated circuit.

After the polishing is completed, pure water is used to wash away the polishing dust and the like adhering to the polished surface. Next, the adhesive tape is peeled off from the surface of the semiconductor wafer, the surface of the semiconductor silicon wafer is washed with pure water, and dried.

[0058]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. The adhesion to the mirror wafer and the peelability from the surface of the semiconductor shown in the examples were evaluated by the following methods.

(1) Evaluation of Adhesive Strength Using a rubber roller having a pressing force of 2 kg / cm ² , a sample tape having a width of 25 mm was attached to the surface of a silicon mirror wafer and placed in an atmosphere at a temperature of 23 ° C. and a relative humidity of 50%. After leaving it for a predetermined time, using a tensilon tensile tester [manufactured by Toyo Baldwin Co., Ltd.], a temperature of 23 ° C. and a peeling angle of 180
At a peeling speed of 30 cm / min, the adhesive force when peeling the sample tape from the surface of the silicon mirror wafer is measured.

(2) Evaluation of peelability Automatic tape sticking machine (manufactured by Takatori Co., Ltd., model; ATM-
1000B), an adhesive tape is attached to the surface of a 4-inch semiconductor wafer, and left in a cassette case for 1 day and 10 days at room temperature.

After standing for 1 day or 10 days, a grinding machine (Infeeder Grinder D manufactured by Disco Co., Ltd.)
FG-821F / 8 type) is used to grind the back surface of the semiconductor wafer.

At this time, of the grindstone used for the first rough cutting,
The particle size is # 320, the particle size is 40 to 60 μm, the particle size of the grindstone used for the final finishing is # 1400, and the particle size is 5 to 12 μm.
m. The peripheral speed of the grindstone is 50 m / sec for the first rough cutting and 57 m / sec for the final finishing.
The feed rate is 6 → 3 μm / sec during the first rough cutting,
At the time of final finishing, it is set to 1.0 → 0.5 μm / sec. The grinding time is 7 minutes and the grinding amount is about 450 μm.

After the grinding is completed, the debris and the like adhering to the grinding surface are washed off with pure water, and then the automatic tape peeling machine (manufactured by Takatori Co., Ltd., model; ATRM-200).
0B) using a Scotch tape (manufactured by 3M Co., Ltd.) installed in the peeling machine, 4 inches (1
01 mmΦ) Peel the adhesive tape from the surface of the semiconductor wafer. This peel test is performed on 20 4-inch semiconductor wafers.

Unseparable number The number of wafers in which the adhesive tape could not be separated from the surface of the 4-inch semiconductor wafer by using the above-mentioned automatic tape peeling machine is defined as the number of unseparable tapes.

Number of Damaged Wafers Of the four 20-inch semiconductor wafers used for the evaluation of peelability, the remaining 4 inch semiconductor wafers that were capable of tape peeling were counted for the number of wafers damaged when peeling. The number of damaged wafers.

Example 1 150 parts by weight of deionized water and polyoxyethylene nonylphenyl ether (surfactant) were placed in a flask equipped with a thermometer, a reflux condenser, a dropping funnel, a nitrogen inlet and a stirrer.
Add 1.0 parts by weight and stir in a nitrogen atmosphere while stirring 70
After the temperature is raised to 0 ° C, 0.5 part by weight of a polymerization initiator is added and dissolved.

Then, 23 parts by weight of methyl methacrylate,
100 parts by weight of a monomer mixture containing 73 parts by weight of 2-ethylhexyl acrylate, 2 parts by weight of glycidyl methacrylate and 2 parts by weight of methacrylic acid are continuously added dropwise over 4 hours. After completion of the dropping, the polymerization reaction was continued by continuing stirring for 3 hours to obtain an acrylic resin water emulsion type adhesive having a solid content of about 47% by weight.

With respect to 100 parts by weight of the solid content of this adhesive,
10 parts by weight of diethylene glycol monobutyl ether as a water-soluble organic compound, 0.5 part by weight of polyoxyethylene nonylphenyl ether as a surfactant, 0.5 part by weight of trimethylolpropane polyglycidyl ether as a cross-linking agent and tetramethylol-tri-β- 0.5 parts by weight of aziridinyl propionate was added to each to prepare a pressure-sensitive adhesive compounding solution.

A base film having a thickness of 1 consisting of two layers of EVA film and PP film formed by the T-die method
A 10 μm film was used, and the EVA layer surface of the film was subjected to corona discharge treatment.

Using a roll coater, the above-mentioned compounded liquid was applied to the corona discharge treated surface of the base film and dried at 90 ° C. to obtain an adhesive tape having an adhesive layer with a thickness of 10 μm.

The obtained adhesive tape was subjected to 4 by the above method.
Affixed to the surface of inch semiconductor wafer for 1 day and 10
I left it in the cassette case for a day. After standing for 1 day or 10 days, the back surface of the semiconductor wafer was ground by the above method. After the grinding was completed, the adhesive tape was peeled from the surface of the 4-inch semiconductor wafer by the above method.

The above-mentioned test was carried out on 20 4-inch semiconductor wafers, and the number of non-peelable sheets and the number of broken sheets when the adhesive tape was peeled from the surface of the 4-inch semiconductor wafers were counted.

As a result, no peeling inability was observed, and
The semiconductor wafer was not damaged. The obtained results are shown in [Table 1].

Further, the adhesive strength of the adhesive tape to the mirror wafer was measured by the above-mentioned method, and the adhesive strength was evaluated immediately after sticking, after standing for 1 day, and after standing for 10 days. The obtained results are shown in [Table 1].

As is apparent from [Table 1], the initial adhesive force is 180 g / 25 mm, and the adhesive force after leaving for 1 day is 200 g.
/ 25mm, adhesive strength after leaving for 10 days is 250g / 25
mm, the initial value of the adhesive force was low, and the change in the adhesive force with time was slight, which was good.

Example 2 An acrylic resin water emulsion type adhesive obtained in the same manner as in Example 1 was added with 10 parts by weight of triethylene glycol monomethyl ether as a water-soluble organic compound and 1 part by weight of polyglycol polyglycidyl ether as a crosslinking agent. Parts were added to prepare a pressure-sensitive adhesive compounding solution.

As the substrate film, an EVA film having a thickness of 150 μm formed by the T-die method was used, and one side of the film was subjected to corona discharge treatment.

Using a roll coater, the above-mentioned compounded liquid was applied to the corona discharge treated surface of the base film and dried at 100 ° C. to obtain an adhesive tape having an adhesive layer with a thickness of 20 μm.

The same test as in Example 1 was carried out on the obtained adhesive tape. The initial value of adhesive strength is low, and
The change in adhesive strength with time was slight and good. Further, no peeling failure was observed, and the semiconductor wafer was not damaged. The obtained results are shown in [Table 1].

Example 3 An acrylic resin water emulsion type pressure-sensitive adhesive obtained in the same manner as in Example 1 was supplemented with 10 parts by weight of diethylene glycol monobutyl ether as a water-soluble organic compound and tetramethylol-tri-β-aziridinini as a crosslinking agent. An adhesive compounding liquid was prepared by adding 0.3 part by weight of lepropionate.

As the base film, a PB film having a thickness of 150 μm formed by the T-die method was used, and one side of the film was subjected to corona discharge treatment.

Using a roll coater, the above-mentioned compounded liquid was applied to the corona discharge treated surface of the base film and dried at 100 ° C. to obtain an adhesive tape having an adhesive layer with a thickness of 40 μm.

The same test as in Example 1 was carried out on the obtained adhesive tape. The initial value of adhesive strength is low, and
The change in adhesive strength with time was slight and good. Further, no peeling failure was observed, and the semiconductor wafer was not damaged. The obtained results are shown in [Table 1].

Comparative Example 1 A solution type acrylic resin pressure-sensitive adhesive (solid content: 50% by weight) obtained by dissolving a monomer mixture having the same composition as in Example 1 in acetone and polymerizing the mixture was used in Example 1. The same film was applied and dried to obtain an adhesive tape having an adhesive layer with a thickness of 10 μm.

The adhesive tape thus obtained was evaluated in the same manner as in Example 1, and the results obtained are shown in Table 1. As shown in [Table 1], the adhesive strength after leaving for 1 day is 1000 g /
Increased to 25 mm and the adhesive strength after standing for 1 day is 1300
increased to g / 25 mm. In addition, peeling is not possible,
Moreover, the semiconductor wafer was damaged during the peeling.

Comparative Example 2 The solid content of the same pressure-sensitive adhesive as the pressure-sensitive adhesive used in Comparative Example 1 was 100.
An adhesive tape was obtained in the same manner as in Comparative Example 1, except that the same amount of the crosslinking agent used in Example 1 was added to parts by weight.

The adhesive tape thus obtained was evaluated in the same manner as in Example 1, and the results obtained are shown in Table 1. As shown in [Table 1], the adhesive strength after standing for 1 day is 600 g / 2.
Increased to 5 mm, the adhesive strength after leaving for 10 days is 1000 g
/ 25 mm. Further, the peeling was impossible, and the semiconductor wafer was damaged during the peeling.

Comparative Example 3 An adhesive tape was obtained in the same manner as in Example 1 except that the crosslinking agent was not added. The obtained adhesive tape was evaluated in the same manner as in Example 1, and the obtained results are shown in [Table 1].
As shown in [Table 1], the initial value of the adhesive strength was high, and the increase in viscosity with time was observed. Further, the peeling was impossible, and the semiconductor wafer was damaged during the peeling.

Comparative Example 4 The amount of the crosslinking agent added was 20 parts by weight (10 parts by weight of trimethylolpropane polyglycidyl ether, 10 parts by weight of tetramethylol-tri-β-aziridinyl propionate).
An adhesive tape was obtained in the same manner as in Example 1 except for the above. The obtained adhesive tape was evaluated in the same manner as in Example 1, and the obtained results are shown in [Table 1]. As shown in [Table 1], the initial adhesive strength was as low as 5 g / 25 mm, and it could not be attached to a 4-inch semiconductor wafer.

Comparative Example 5 0.005 parts by weight of the crosslinking agent of Example 1 (0.003 parts by weight of trimethylolpropane polyglycidyl ether, 0.002 parts by weight of tetramethylol-tri-β-aziridinyl propionate) An adhesive tape was obtained in the same manner as in Example 1 except that the adhesive tape was added. The obtained adhesive tape was evaluated in the same manner as in Example 1, and the obtained results are shown in [Table 1]. As shown in [Table 1], the initial value of the adhesive strength was high, and the increase in viscosity with time was observed. Further, the peeling was impossible, and the semiconductor wafer was damaged during the peeling.

Comparative Example 6 An adhesive tape was obtained in the same manner as in Example 1 except that 0.04 parts by weight of the nonionic surfactant was added during the polymerization of the adhesive. The obtained adhesive tape was evaluated in the same manner as in Example 1, and the obtained results are shown in [Table 1]. As shown in [Table 1], as shown in [Table 1], the initial value of the adhesive strength was high and the increase in viscosity over time was observed. Further, the peeling was impossible, and the semiconductor wafer was damaged during the peeling.

Comparative Example 7 An adhesive tape was obtained in the same manner as in Example 1 except that 19 parts by weight of a nonionic surfactant was added after the completion of the polymerization reaction. The obtained adhesive tape was evaluated in the same manner as in Example 1, and the obtained results are shown in [Table 1]. [Table 1]
As shown in, the initial adhesive strength was as low as 20 g / 25 mm and it could not be attached to a 4-inch semiconductor wafer.

Comparative Example 8 An adhesive tape was obtained in the same manner as in Example 1 except that the water-soluble compound (diethylene glycol monobutyl ether) was not added. Example 1 of the obtained adhesive tape
Evaluations were made in the same manner as above, and the obtained results are shown in [Table 1].
As shown in [Table 1], the initial value of the adhesive strength was high, and the increase in viscosity with time was observed. Further, the peeling was impossible, and the semiconductor wafer was damaged during the peeling.

[0094]

[Table 1]

[0095]

According to the present invention, it is possible to obtain an adhesive tape for grinding the back surface of a semiconductor wafer, which has a low initial adhesive force to the semiconductor mirror wafer and a small increase in viscosity over time. Also,
A backside grinding method for a semiconductor wafer is provided, which comprises applying the tape to the front surface of the semiconductor wafer.

Therefore, when the adhesive tape is attached to the front surface of the semiconductor wafer and the back surface of the semiconductor wafer is ground, damage to the semiconductor wafer can be prevented and the adhesive tape can be easily peeled off even if left for about 10 days. The workability is remarkably improved without damaging the semiconductor wafer during the peeling work.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 28, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0035

[Correction method] Change

[Correction content]

Examples of the vinyl monomer copolymerizable with the acrylic acid alkyl ester monomer or the methacrylic acid alkyl ester monomer and the monomer having a carboxyl group include, for example, hydroxyethyl acrylate,
Examples thereof include hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, acrylamide, methacrylamide, dimethylaminoalkyl acrylate, dimethylaminoalkyl methacrylate, vinyl acetate, styrene and acrylonitrile.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0050

[Correction method] Change

[Correction content]

When using the adhesive tape, first, the release film is peeled from the surface of the adhesive layer, and then the adhesive tape is attached to the surface of the semiconductor wafer, that is, the surface on which the integrated circuit is incorporated. Trim to fit the shape of the semiconductor wafer by machine or manually.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction content]

The peripheral speed of the grindstone is 10 to 100 m / sec at the first rough cutting, and 15 to 10 at the final finishing.
120 m / sec is preferable. The feed speed of the grindstone is preferably 2 to 10 μm / sec at the first rough cutting and 0.1 to 2 μm / sec at the final finishing. Considering productivity and the like, the polishing time is preferably 1 to 20 minutes.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoko Takeuchi Mitsui Toatsu Chemical Co., Ltd. 2-1, Tangodori, Minami-ku, Nagoya-shi, Aichi

Claims (6)

[Claims] 1. A method for grinding a back surface of a semiconductor wafer, wherein 100 parts by weight of a solid content of an acrylic resin water emulsion type adhesive is applied to one side of a base film made of a synthetic resin film monolayer or multilayer. , A nonionic surfactant 0.05 to 10 parts by weight, an epoxy crosslinking agent, an aziridine crosslinking agent, and a crosslinking agent 0.01 selected from the group consisting of a mixture of an epoxy crosslinking agent and an aziridine crosslinking agent.
10 parts by weight and 0.1-100 parts by weight of a water-soluble organic compound having a boiling point of 100 ° C. or more are applied, dried, and coated with an acrylic resin water emulsion type pressure sensitive adhesive coating solution.
50-450g adhesion to mirror wafer at 3 ° C
/ 25mm adhesive tape provided with an adhesive layer,
A method for grinding a back surface of a semiconductor wafer, which is attached to a surface of a semiconductor wafer on which an integrated circuit is incorporated and ground the back surface. 2. The method for grinding a semiconductor wafer according to claim 1, wherein the crosslinking agent is a mixture of an aziridine crosslinking agent and an epoxy crosslinking agent. 3. The mixing ratio of the crosslinking agent is 0.1 to 10 parts by weight of the aziridine crosslinking agent to 1 part by weight of the epoxy crosslinking agent.
The backside grinding method for a semiconductor wafer according to claim 2, wherein the backside grinding is performed by weight. 4. A water-based acrylic resin adhesive of 100 parts by weight as a solid content on one side of a base film made of a monolayer or a multi-layer of a synthetic resin film, and a nonionic surfactant of 0.05 to. 10 parts by weight, 0.01 to 10 parts by weight of a crosslinking agent selected from the group consisting of an epoxy crosslinking agent, an aziridine crosslinking agent, and a mixture of an epoxy crosslinking agent and an aziridine crosslinking agent, and a boiling point of 100 ° C or higher. An acrylic resin water emulsion type pressure-sensitive adhesive coating solution containing 0.1 to 100 parts by weight of a certain water-soluble organic compound is applied and dried, and the adhesion to a mirror wafer at 23 ° C. is 50 to 450 g / 25 mm. An adhesive tape for backside grinding of a semiconductor wafer, which is characterized in that 5. The adhesive tape for backside grinding of a semiconductor wafer according to claim 4, wherein the crosslinking agent is a mixture of an aziridine crosslinking agent and an epoxy crosslinking agent. 6. The mixing ratio of the crosslinking agent is 0.1 to 10 parts by weight of the aziridine crosslinking agent to 1 part by weight of the epoxy crosslinking agent.
The adhesive tape for backside grinding of a semiconductor wafer according to claim 5, wherein the adhesive tape is a weight part.