JPH097932A - Method for removing resist film image - Google Patents

Abstract

PURPOSE: To provide a method for easily and surely peeling off an unnecessary resist film image on a semiconductor substrate, without implanting the impurity ions in the resist material into the semiconductor substrate nor affecting the operation environment nor causing the trouble of contaminating the semiconductor substrate. CONSTITUTION: On a resist film image on a semiconductor substrate, curing type pressure sensitive adhesive sheets, which provide an adhesion less than 150g/10mm width when it is peeled at 180 deg. from the dummy wafer (mirror plane side), are affixed after curing. After permitting the partial curing type pressure sensitive adhesive to permeate into the recessed part of the resist pattern by applying pressure or heat, the adhesive sheets are cured. Then, the adhesive sheets and the resist material are peeled together.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing an unnecessary resist film image on a semiconductor substrate in manufacturing a semiconductor integrated circuit device or the like.

[0002]

2. Description of the Related Art In the manufacture of a semiconductor integrated circuit device, a resist material is applied onto a semiconductor substrate such as a silicon wafer, and a predetermined resist film image (resist pattern) is formed by a normal photo process. As the mask, for example, various treatments such as ion implantation of P ⁺ , B ⁺ , As ⁺ , Sb ^+, etc., and etching are performed on the opening. At this time, the above ions are also injected into the upper surface layer of the resist film image. After that, the unnecessary resist film image is removed, and a predetermined circuit is formed. Further, in order to form the next circuit, the cycle of applying the resist material again is repeated. In forming such a circuit, as a method for removing an unnecessary resist film image, a method using ion assist etching (ashing means), a solvent (peeling solution) or a chemical is known.

[0003]

However, when the above-mentioned ions are injected into the upper surface layer of the resist film image and the upper surface layer of the resist film image is cured and deteriorated, the upper surface layer has high heat resistance and reaction. Due to its low property, the usual ashing means requires a long time for the removal work, which makes the removal practically difficult. Furthermore, the impurity ions in the resist material and the implanted ions remain on the semiconductor substrate and are implanted into the semiconductor substrate by the subsequent heat treatment, making it impossible to construct a semiconductor integrated circuit as designed and degrading the characteristics of the semiconductor device. Let In addition, the method using a solvent or a chemical has a problem that the working environment is damaged.

Japanese Unexamined Patent Publication (Kokai) No. 6-302509 proposes a method in which a resist remover is attached to the upper surface of a resist material, and the resist material on the article is removed by peeling the resist remover. According to this method, there are few problems as described above, which are unavoidable by the method using ashing means, solvent, or chemicals, but since the adhesive force is large in the portion where the resist film image does not exist, the wafer is removed at the time of peeling the resist removal body A part of the removed body may remain on the upper surface and contaminate the semiconductor substrate.

Therefore, according to the present invention, an unnecessary resist film image on a semiconductor substrate can be obtained without impairing impurity ions in the resist material into the semiconductor substrate or impairing the working environment. It is an object of the present invention to provide a simple and reliable method of peeling and removing without causing contamination and any problems.

[0006]

The inventors of the present invention have conducted extensive studies to achieve the above-mentioned object, and as a result, as a result, a specific curable pressure-sensitive adhesive sheet was used as a resist remover, which was used as a semiconductor. By applying a specific state on the resist film image on the substrate and peeling it after curing the pressure-sensitive adhesive, problems of conventional ashing means, methods using solvents or chemicals, for example, impurities in the resist material It is possible to remove the resist film image easily and reliably without causing any problems when ions are injected into the semiconductor substrate or when the working environment is damaged, and without causing any problems with the contamination of the semiconductor substrate. They have found the present invention and completed the present invention.

That is, according to the present invention, in a method of removing an image made of a resist material existing on a semiconductor substrate, a cured dummy wafer (mirror side) is formed on the resist film image.
Adhesion of a curable pressure-sensitive adhesive sheet with a 180 degree peel adhesive strength of less than 150 g / 10 mm width is applied, and a part of the curable pressure-sensitive adhesive is permeated into the concave portion of the resist pattern by applying pressure or heat. After that, the adhesive sheet is cured, and then the adhesive sheet and the resist material are integrally peeled off.

[0008]

Construction and operation of the invention The curable pressure-sensitive adhesive sheets used in the present invention have a thickness of about 10 to 180 .mu.m on a film substrate.
m layer of curable pressure-sensitive adhesive is applied to form sheet or tape.
The adhesive has a pressure-sensitive adhesive property and includes various types of adhesives having a property of being cured by active energy rays such as heat or ultraviolet rays. . From the viewpoint of not exerting a thermal adverse effect on the curing workability and the circuit board, an ultraviolet-curable pressure-sensitive adhesive is preferable, and in this case, the film substrate is made of polyethylene, polypropylene, polyethylene terephthalate, or the like. An ultraviolet-transparent resin film having a thickness of about 10 to 100 μm is used.

In the present invention, a curable pressure-sensitive adhesive having such a constitution is used as a curable pressure-sensitive adhesive.
180 degree peel adhesion to wafer (mirror side) is 150
less than g / 10mm width, preferably 10-100g / 10mm
The width is selected and used. If the adhesive strength after curing is 150 g / 10 mm width or more, there is a problem in the peeling process, and problems such as contamination of the semiconductor substrate due to adhesive residue easily occur, which hinders easy and reliable peeling and removal of the resist film image. Easy to come. The 180-degree peeling adhesive strength to the dummy wafer (mirror surface side) before curing is 150 g /
10 mm width or more, preferably 200 to 1,000 g / 10
It should be mm wide.

As a curable pressure-sensitive adhesive having such adhesive properties, a pressure-sensitive adhesive polymer containing a non-volatile low molecular weight substance having at least one polymerizable carbon-carbon double bond in the molecule is contained. What is formed is preferable. As the pressure-sensitive adhesive polymer, any of various known polymers applied to general pressure-sensitive adhesives can be used, but a particularly preferable polymer.
Examples of the acrylic polymer include an acrylic polymer and / or a methacrylic acid alkyl ester as a main monomer.

This acrylic polymer is a main monomer described above, that is, an ester of acrylic acid or methacrylic acid with an alcohol having a carbon number of usually 12 or less, and a monomer having a carboxyl group or a hydroxyl group if necessary. ,
These can be synthesized by using other modifying monomers and polymerizing them by a method such as solution polymerization, emulsion polymerization, suspension polymerization or bulk polymerization according to a conventional method.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, maleic acid, and itaconic acid, and examples of the hydroxyl group-containing monomer include hydroxyethyl acrylate and hydroxypropyl acrylate. Are used respectively. The amount of these monomers used is usually preferably 20% by weight or less in all the monomers. As other modifying monomers, vinyl acetate, vinyl propionate, styrene, acrylonitrile, acrylamide, glycidyl methacrylate and the like are used. The amount of these reforming monomers used is usually preferably 50% by weight or less based on the total amount of the main monomers.

In the synthesis of the above-mentioned acrylic polymer, as the copolymerization monomer, one having two or more polymerizable carbon-carbon double bonds is used, or the acrylic polymer after synthesis is polymerized. By introducing a polymerizable carbon-carbon double bond into the molecule of the acrylic polymer by, for example, chemically bonding a compound having a carbon-carbon double bond by a reaction between functional groups, this polymer You may make it participate in a polymerization hardening reaction by irradiation of an ultraviolet ray itself.

The acrylic polymer composed of such a monomer has a weight average molecular weight of usually 30.
It is preferably from 10,000 to 2,000,000. If the molecular weight is too low, when a non-volatile low molecular weight compound having one or more polymerizable carbon-carbon double bonds in the molecule is blended with it, it will have a low viscosity and will cause inconveniences such as flowing during storage. Easy,
If it becomes too high, handling problems are likely to occur.

A non-volatile low molecular weight compound having one or more polymerizable carbon-carbon double bonds in the molecule (hereinafter referred to as a curable compound) compounded in the pressure-sensitive adhesive polymer including the acrylic polymer. ) Has excellent compatibility with the above-mentioned polymer and contributes to fluidization of the entire adhesive, giving good results for fluid penetration and adhesion to the concave portion of the resist pattern, and it is polymerized by heating or irradiation with ultraviolet rays. To cure the entire adhesive. In order to exert such effects, it is preferable that the molecular weight is 10,000 or less, and in particular, the molecular weight is 5,000 or less so that the three-dimensional reticulation of the adhesive layer during curing can be efficiently performed. It is good to be

Specific examples of such curable compounds include, for example, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, and commercially available oligos. Ester (meth) acrylate
The following urethane (meth) acrylate oligomers
(Meth) acrylate compounds such as In addition, the organopolysiloxane composition as described in JP-B-5-25907 (particularly in the section of the prior art) may be used.

Urethane (meth) acrylate-based oligomers include polyol compounds, polyvalent isocyanate compounds,
It is synthesized from hydroxy (meth) acrylate and the like. Polyol compounds include ethylene glycol
Polypropylene glycol, diethylene glycol, butanediol, pentanediol, trimethylolethane, trimethylolpropane, pentaerythritol, etc. , Phenylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate
, Dimethyldiphenyl diisocyanate, dicyclohexylmethane diisocyanate, xylene diisocyanate
But hydroxy (meth) acrylate has 2-
Hydroxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate, pentaerythritol
There is Lutri (meta) acrylate.

Such a curable compound is used in an amount of 1 to 200 parts by weight, based on 100 parts by weight of the pressure-sensitive adhesive polymer.
Preferably 5 to 150 parts by weight, more preferably 10 to 1
It is used in an amount of 20 parts by weight, more preferably 20 to 100 parts by weight. If this amount is too small, the peeling effect of the resist film image may not be sufficient, and if it is too large, the adhesive may flow out during storage, which is not preferable.

The curable pressure-sensitive adhesive includes
A thermal polymerization initiator such as benzoylperoxide or azobisisobutyronitrile that generates radicals by heating is added. In the case of photo-curing such as ultraviolet rays, benzoin,
Benzoin ethyl ether, dibenzyl, isopropyl benzoin ether, benzophenone, Michler's ketone chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, acetophenone diethyl ketate
Photopolymerization initiators such as benzyl, benzyl dimethyl ketal, α-hydroxycyclohexyl phenyl ketone, and 2-hydroxymethyl phenyl propane are added. These polymerization initiators are used in the range of 0.1 to 15 parts by weight with respect to 100 parts by weight of the pressure sensitive adhesive polymer.

In addition, in order to improve the workability when it is attached to a semiconductor substrate, this curable pressure-sensitive adhesive is used to crosslink the pressure-sensitive adhesive polymer to increase the cohesive force as an adhesive. Crosslinking agent, for example, an acrylic polymer having a carboxyl group or a hydroxyl group, polyisocyanate, polyepoxy, various metal salts, chelate compounds and the like as a polyfunctional compound that reacts with the above functional groups. Good. The amount of the polyfunctional compound used may be appropriately determined within the range of 20 parts by weight or less with respect to 100 parts by weight of the pressure-sensitive adhesive polymer according to the molecular weight of the polymer.

Further, such a curable pressure-sensitive adhesive may contain a filler such as finely divided silica for the same purpose of use as the above-mentioned polyfunctional compound. Further, in this curable pressure-sensitive adhesive, in addition to various known additives such as tackifying resin, colorant, and antiaging agent, hydroquinone, hydroquinone monomethyl ether, benzoquinone, butyl catechol, tri-p If desired, a polymerization inhibitor such as -nitrophenylmethyl may be included. The amounts of these various additives used may be the usual amounts known as curable pressure-sensitive adhesives.

In the present invention, the curable pressure-sensitive adhesive sheet thus constructed is used to remove the resist film image as follows. First, a curable pressure-sensitive adhesive sheet is pasted on the resist film image on the semiconductor substrate, and a part of the curable pressure-sensitive adhesive is permeated into the concave portion of the resist pattern by applying pressure and / or heating, Adhere sufficiently. Normal resist patterns often adhere to the substrate after circuit formation in a concave shape or have fine irregularities on the surface at the stage of circuit formation. Therefore, the peeling operation is facilitated.

The pressurization or heating is for promoting the integration of the resist material and the adhesive by permeation / adhesion of the adhesive to the concave portion of the resist pattern, and the conditions are as follows. It may be appropriately determined according to the adhesion state of the resist pattern and the type of the adhesive. Generally, under a wide range of conditions from finger pressure to roll pressure, the adhesive does not harden or stick to the side surface, usually 10 to 20
You can choose a temperature of 0 ° C. Only pressurization or heating may be used.

After the attachment process is performed as described above, the adhesive sheet is subjected to a predetermined curing process for almost completely curing it. This curing process is based on the type of adhesive sheet.
Although thermal curing or photo-curing is selected, as described above, considering the thermal influence on the semiconductor substrate, photo-curing, especially curing by irradiation of ultraviolet rays is desirable.
The irradiation dose should be 5,000 mj / cm ² .

By this hardening treatment, the adhesive is hardened in the state of being integrated with the resist material, and the elastic modulus thereof is remarkably increased, and along with this, the adhesive force between the resist material and the semiconductor substrate is greatly reduced. Therefore, it is easy to peel off after curing,
Little pollution. In addition, since the adhesive penetrates into the recesses of the resist pattern and hardens, the adhesive sheet is peeled off after the curing, so that the resist material on the semiconductor substrate is It can be easily and completely peeled off. In addition, the particles do not adhere to the surface without the resist film image.

Moreover, according to the method of peeling and removing the resist film image as described above, the work is prolonged as in the conventional method using the ashing means and the impurity ions in the resist material are injected into the semiconductor substrate. There is no worry at all, and there is no particular concern that the working environment deteriorates as in the conventional method using a solvent.

[0027]

As described above, according to the method of the present invention,
The resist film image on the semiconductor substrate, the impurity ions in the resist material is injected into the semiconductor substrate, without any problems when working environment is harmed, and without causing the problem of contamination of the semiconductor substrate, It can be removed easily and reliably.

[0028]

EXAMPLES Next, the present invention will be described more concretely by reference examples, examples and comparative examples. In the following, "parts" means "parts by weight".

Reference Example 1 On the surface of a 5-inch silicon wafer (semiconductor substrate), a positive photoresist consisting of cresol novolak resin, naphthoquinone diazide sulfonic acid ester of polyhydroxy compound, and ethyl lactate was applied, heated, exposed, After development, a resist pattern (film image) was formed on the entire surface, and then P ⁺ ions were implanted over the entire surface at an acceleration energy of 80 KeV at a dose of 1 × 10 ¹⁶ ions / cm ² .

Example 1 80 parts of n-butyl acrylate, 15 ethyl acrylate
Part, a monomer mixture consisting of 5 parts of acrylic acid was subjected to solution polymerization at 60 ° C. for 12 hours in a nitrogen stream using 150 parts of ethyl acetate and 0.1 part of azobisisobutyronitrile, and the weight average molecular weight was 560,000 solutions of acrylic polymer A were obtained.

Next, to this solution A, 10 parts of polyethylene glycol diacrylate and dipentaerythritol as a curable compound were added to 100 parts of acrylic polymer.
10 parts of hexahexaacrylate, 30 parts of trimethylolpropane triacrylate, 3 parts of diphenylmethane diisocyanate as a polyfunctional compound, α as a polymerization initiator
3 parts of -hydroxycyclohexyl phenyl ketone were mixed uniformly to prepare a curable pressure-sensitive adhesive solution.

This curable pressure-sensitive adhesive solution was applied onto a polyester film having a thickness of 50 μm so that the thickness after drying would be 45 μm, and dried at 130 ° C. for 3 minutes to give a curable pressure-sensitive adhesive. A pressure-sensitive adhesive sheet was prepared. This adhesive sheet
The 180 degree peeling adhesive strength to the dummy wafer (mirror surface side) before curing and the adhesive strength after curing are as follows.
When measured, the 180 degree peel adhesion before curing was 2
35g / 10mm width, the same adhesive strength after curing is 13g / 10mm
It was width.

<Measurement of 180 ° Peel Adhesion> As a dummy wafer, a 4-inch silicon dummy wafer (single-sided polish) manufactured by Shin-Etsu Semiconductor was used, and a width of 1
A strip-shaped adhesive sheet having a length of 0 mm and a length of 100 mm was attached and heated on a hot plate (130 ° C.) for 3 minutes, and then the adhesive strength before curing was measured. Also, after the above heating,
Ultraviolet rays (4
(6 mj / cm ² · sec) for 23 seconds to cure the pressure-sensitive adhesive, and the adhesive strength after curing was measured. Each measurement is at 23 ℃, 65% RH, peeling speed 300mm
/ Min, and the peeling angle was 180 °.

Next, the above-mentioned adhesive sheet was attached to the entire surface of the resist film image of the P ⁺ ion-implanted silicon wafer according to Reference Example 1 and heated and pressed at 130 ° C. for 3 minutes to form an adhesive. After infiltrating a part of the
Ultraviolet rays were irradiated at 1,000 mJ / cm ² with a high pressure mercury lamp to cure the adhesive sheet. After that, when the adhesive sheet was peeled off, the resist film image was easily peeled off together with the adhesive sheet. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Example 2 To the solution A of the acrylic polymer obtained in Example 1, 100 parts of the acrylic polymer, 20 parts of polyethylene glycol methacrylate as a curable compound, and trimethylolpropane triacrylate were used as curable compounds. -30 parts, 3 parts of tolylene diisocyanate as a polyfunctional compound, and 5 parts of α-hydroxycyclohexylphenyl ketone as a polymerization initiator are uniformly mixed to prepare a solution of a curable pressure-sensitive adhesive. did.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 538 g / 10 mm width, and the adhesive force after curing was 12 g / 10 mm width.

Then, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1, and the resist film image showed this adhesive sheet. -It was easily peeled off together with the grate. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Example 3 90 parts of n-butyl acrylate and 10 parts of acrylonitrile
Part, and a monomer mixture consisting of 5 parts of acrylic acid were polymerized in the same manner as in Example 1 to obtain a solution B of an acrylic polymer having a weight average molecular weight of 620,000.

Next, in this solution B, 100 parts of an acrylic polymer was used, and tetramethylo as a curable compound.
Lumethan triacrylate 30 parts, dipentaerythritol hexahexaacrylate 5 parts, polyfunctional compound diphenylmethane diisocyanate 3 parts, polymerization initiator α-hydroxycyclohexyl phenyl ketone 5 parts Were uniformly mixed to prepare a curable pressure-sensitive adhesive solution.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 345 g / 10 mm width, and the adhesive force after curing was 14 g / 10 mm width.

Then, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1. -It was easily peeled off together with the grate. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Example 4 In the solution A of the acrylic polymer obtained in Example 1, 100 parts of the acrylic polymer, 10 parts of dipentaerythritol hexaacrylate as a curable compound, and polyethylene glycol diacrylate were used. 10 parts, 3 parts of diphenylmethane diisocyanate as a polyfunctional compound, and 5 parts of α-hydroxycyclohexyl phenyl ketone as a polymerization initiator are uniformly mixed to prepare a solution of a curable pressure-sensitive adhesive. Prepared.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 300 g / 10 mm width, and the adhesive force after curing was 64 g / 10 mm width.

Then, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1. The resist film image showed that this adhesive sheet. -It was easily peeled off together with the grate. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Example 5 To the solution B of the acrylic polymer obtained in Example 3, 100 parts of the acrylic polymer, 30 parts of trimethylolpropane triacrylate as a curable compound, and dipentaerythritol were used as curable compounds. -Hexa acrylate 5 parts, diphenyl methane diisocyanate 3 parts as a polyfunctional compound, and α-hydroxycyclohexyl phenyl ketone 5 parts as a polymerization initiator are uniformly mixed to give a curable pressure-sensitive adhesive. Was prepared.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 465 g / 10 mm width, and the adhesive force after curing was 17 g / 10 mm width.

Then, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1. -It was easily peeled off together with the grate. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Example 6 Solution B of the acrylic polymer obtained in Example 3 was mixed with 100 parts of the acrylic polymer and 20 parts of polyethylene glycol methacrylate as a curable compound and phenoxypolyethylene glycol. 40 parts, 0.01 part of polyepoxy compound as a polyfunctional compound, α- as a polymerization initiator
5 parts of hydroxycyclohexyl phenyl ketone were uniformly mixed to prepare a solution of curable pressure-sensitive adhesive.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 357 g / 10 mm width, and the adhesive force after curing was 17 g / 10 mm width.

Then, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1, and the resist film image showed this adhesive sheet. -It was easily peeled off together with the grate. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Example 7 A monomer mixture consisting of 50 parts of 2-ethylhexyl acrylate, 50 parts of methyl acrylate and 10 parts of acrylic acid was polymerized in the same manner as in Production Example 1 to give a weight average molecular weight of 90.
A solution C of many acrylic polymers was obtained.

Next, to this solution C, 100 parts of an acrylic polymer was added, and trimethylol as a curable compound.
30 parts of propane triacrylate, 3 parts of diphenylmethane diisocyanate as a polyfunctional compound, and 5 parts of α-hydroxycyclohexyl phenyl ketone as a polymerization initiator are uniformly mixed to give a curable composition. A solution of pressure sensitive adhesive was prepared.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 720 g / 10 mm width, and the adhesive force after curing was 23 g / 10 mm width.

Next, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1, and the resist film image showed that this adhesive sheet. -It was easily peeled off together with the grate. No adhesive was found on the surface of the wafer, and it was hardly contaminated.

Comparative Example 1 In the solution A of the acrylic polymer obtained in Example 1, 100 parts of the acrylic polymer, 60 parts of polyethylene glycol dimethacrylate as a curable compound, and trimethylolpropane triacrylate were used as curable compounds. -90 parts, 30 parts dipentaerythritol hexaacrylate, 3 parts diphenyl methane diisocyanate as a polyfunctional compound, 5 parts α-hydroxycyclohexyl phenyl ketone as a polymerization initiator, are uniformly mixed. Then, a solution of the curable pressure-sensitive adhesive was prepared.

Using this curable pressure-sensitive adhesive solution,
A curable pressure-sensitive adhesive sheet was produced in the same manner as in Example 1. The 180 ° peeling adhesive strength of the adhesive sheet to the dummy wafer (mirror side) before curing and the same adhesive strength after curing were measured in the same manner as above. The force was 153 g / 10 mm width, and the adhesive force after curing was 288 g / 10 mm width.

Then, using this curable pressure-sensitive adhesive sheet, an attempt was made to peel off the resist film image on the silicon wafer in the same manner as in Example 1. However, the resist film image is not separated and removed integrally with this adhesive sheet,
The adhesive force to the peripheral portion of the wafer (resist-uncoated portion) was too large to perform the peeling work easily, failing to achieve the intended purpose.

Claims (1)

[Claims] 1. A method for removing an image made of a resist material existing on a semiconductor substrate, wherein a 180-degree peeling adhesive force to a dummy wafer (mirror side) after curing is less than 150 g / 10 mm width on the resist film image. Curable pressure-sensitive adhesive sheets that will be used as the adhesive sheet are adhered, and a portion of the curable pressure-sensitive adhesive is permeated into the recesses of the resist pattern by applying pressure or heat, and then the adhesive sheets are cured. Then, a method for removing a resist film image, characterized in that the adhesive sheet and the resist material are then peeled off integrally.