JPH06196398A - Removal method of resist-film image - Google Patents

Abstract

PURPOSE:To provide a method wherein an image into which ions have been implanted on a semiconductor substrate and which is composed of an inessential resist film is removed in the manufacture of a semiconductor integrated circuit device. CONSTITUTION:In the removal method of an image which exists on a semiconductor substrate and which is composed of a resist material, a substance having a function of easily removing the image is brought into contact with the resist- film image as a pretreatment, an adhesive sheet or the like is then pasted on the resist-film image, and the adhesive sheet or the like and the resist material are stripped integrally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor substrate which has become unnecessary in the manufacture of a semiconductor integrated circuit device.
The present invention relates to a method of removing an image formed of a resist film into which ions are implanted.

[0002]

2. Description of the Related Art In manufacturing 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 is formed by a normal photo process. Using this as a mask, ions of P ⁺ , B ⁺ , As ⁺ , Sb ^+, etc. are implanted at a high concentration in the openings.
At this time, the ions are also injected into the upper surface layer of the resist film image. Next, the unnecessary resist film image is generally removed from the semiconductor substrate by ion-assisted etching (ashing means) or a solvent.

[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 this image is cured and deteriorated, the upper surface layer has high heat resistance and reactivity. Therefore, the conventional ashing means has a problem that the removal work requires a long time and is practically difficult to remove. Furthermore, when the normal ashing means is used, the impurity ions in the resist material and the ions remain on the semiconductor substrate and are injected into the semiconductor substrate by the subsequent heat treatment, making it impossible to construct the semiconductor integrated circuit as designed. Therefore, there is a problem that the characteristics of the semiconductor device are deteriorated. Therefore, the present invention provides a simple and reliable method for removing an unnecessary resist film image on a semiconductor substrate, particularly an ion-implanted resist film image, by a novel method completely different from the conventional method. To aim.

[0004]

Means for Solving the Problems The inventors of the present invention, in removing an unnecessary resist film image on a semiconductor substrate, carry out a specific pretreatment and then use an adhesive sheet to improve ion implantation. The inventors have found that the formed resist film image can be removed easily and reliably, 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, as a pretreatment, a resist film image is brought into contact with a substance having a function of facilitating the removal of the image, The present invention relates to a method for removing a resist film image, which comprises adhering adhesive sheets on a resist film image and peeling the adhesive sheet and the resist material together.

[0006]

In the method of removing a resist film image of the present invention, first, as a pretreatment, the resist film image is brought into contact with a substance having a function of facilitating the removal of the image. Examples of the method of contacting such a substance include a method of contacting the substance as a solution or a method of contacting a vaporized substance.

In the present invention, water such as ultrapure water or pure water can be used as the first substance having the function of facilitating the removal of the resist film image, and in particular, the prevention of contamination of the semiconductor substrate is required. Therefore, ultrapure water is preferable. The method of bringing the ultrapure water or pure water into contact with the image is not particularly limited, but, for example, spraying of water or immersion in water can be adopted. In this case, the water temperature is as high as possible, usually 80 ° C. or higher, preferably 100 ° C., and if this temperature is too low, the removal effect is difficult to obtain. Here, the spraying amount and the immersion time are not particularly limited, and the spraying amount may be a small amount, and the immersion time may be about 5 seconds or more, preferably about 40 seconds.

Further, in the present invention, steam such as vaporized ultrapure water or pure water can be sprayed on the image or left in a steam atmosphere. Here, the amount of spraying and the standing time are not particularly limited, and are, for example, at 85 ° C.-85% RH for about 10 minutes or more.

In the present invention, after carrying out the above-mentioned contact treatment, preferably water is removed from the resist film image surface by a usual drying means such as spraying with dry N ₂ , and then the adhesive sheets are removed. And the adhesive material and the resist material are integrally peeled off. At this time, when ultrapure water or pure water is brought into contact with the image in a solution or vapor state, the water or water vapor diffuses from the surface of the resist film image to the interface with the semiconductor substrate, and the semiconductor substrate and the resist film image. The ion-implanted resist film image can be satisfactorily removed from the semiconductor substrate together with the adhesive sheets by lowering the adhesive force with the adhesive sheets and then peeling off the adhesive sheets.

The adhesive sheet used here is not particularly limited, and an ordinary pressure-sensitive adhesive sheet can be used, but from the viewpoint of preventing contamination of the semiconductor substrate, a curable pressure-sensitive adhesive sheet described later is used. It is preferable.

The second substance having a function of facilitating the removal of the resist film image in the present invention is a water-affinity compound. As such a water-affinity compound,
At least one of alcohols, ketones, and esters having a boiling point of 98 ° C. or lower and an alkyl group having 3 or less carbon atoms is preferable. Other water-affinity compounds are not preferable because their effects are reduced even when they are brought into contact with the resist film image.

Specific examples of the water-affinity compound that is particularly preferable in the present invention include alcohols such as methyl alcohol and ethyl alcohol, and ketones such as methyl alcohol and ethyl alcohol.
Examples of the esters such as acetone and ethyl methyl ketone include ethyl acetate.

The method of bringing these water-affinity compounds into contact with the resist film image is not particularly limited, but similar to the case of the above-mentioned water, for example, spraying a solution of the water-affinity compound, immersing in a solution, or steam. It is possible to employ spraying of the converted water-affinity compound or leaving it in a vaporized atmosphere.

In the present invention, after carrying out the above-mentioned contact treatment, preferably the water adhering to the image surface of the resist film is removed by a usual drying means such as spraying with dry N ₂ , and then the adhesive sheet or the like. And the adhesive material and the resist material are integrally peeled off. At this time, by bringing the water-affinity compound into contact with the image in a solution or vapor state, the water-affinity compound diffuses from the surface of the resist film image to the interface with the semiconductor substrate, and the semiconductor substrate and the resist film. By reducing the adhesive force with the image and then peeling off the adhesive sheets, the ion-implanted resist film image can be satisfactorily removed from the semiconductor substrate together with the adhesive sheets.

Here, it is preferable that the temperature of the semiconductor substrate when the adhesive sheets are attached is set to not more than the boiling point of the water or the water-affinitive compound, and usually about 5 to 50 ° C. is desirable. If this temperature is too high, the evaporation of water or a water-affinity compound from the resist film image is promoted, and the effect of the treatment tends to decrease.

The adhesive sheets used in the present invention have particularly good affinity with the resist agent from the viewpoint of preventing contamination of the semiconductor substrate, and particularly when the water-affinity compound is used for pretreatment. It is preferable to attach adhesive sheets using a curable pressure-sensitive adhesive. At this time, the resist material and the adhesive are favorably adhered and integrated, but in order to promote the adherence and integration, heating and / or pressure may be applied during the adhering.

In such a curable pressure-sensitive adhesive, a pressure-sensitive adhesive polymer is made to contain a non-volatile compound having a good affinity with a resist material and having at least one unsaturated double bond in the molecule. Is preferred.

As the above-mentioned pressure-sensitive adhesive polymer, any of various known polymers applicable to general pressure-sensitive adhesives can be used, and particularly preferable polymers are alkyl acrylate and / or methacrylic acid. An acrylic polymer having an alkyl ester as a main monomer can be used.

This acrylic polymer is, in addition to the above-mentioned main monomer, that is, an ester of acrylic acid or methacrylic acid and an alcohol having a carbon number of usually 12 or less, a monomer having a carboxyl group or a hydroxyl group if necessary, and other modifications. It can be obtained by polymerizing these using a monomer for use by a conventional method such as solution polymerization, emulsion polymerization, suspension polymerization and bulk polymerization.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, maleic acid,
Itaconic acid or the like is used, and as the hydroxyl group-containing monomer, for example, hydroxyethyl acrylate, hydroxypropyl acrylate or the like is used. The amount of these monomers used is preferably 20% by weight or less based on the total amount of all the monomers.

As the above-mentioned other modifying monomers, vinyl acetate, vinyl propionate, styrene, acrylonitrile, acrylamide, couglycidyl methacrylate and the like are used. The amount of these modifying monomers used is preferably 50% by weight or less in the total amount with the main monomer.

The acrylic polymer composed of such monomers 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, the viscosity will be low when the non-volatile compound described below is blended therein, and problems such as flowing during storage are likely to occur, and if it is too high, handling problems are likely to occur. Further, the acrylic polymer preferably has a glass transition point of 250 ° K or lower in consideration of workability at the time of image removal. If it is higher than this, it tends to be too hard after curing and the peeling tends to be heavy. However, it does not try to eliminate all the use of acrylic polymers having such a high glass transition point,
Of course, it can be used in some cases.

In the present invention, the above-mentioned pressure-sensitive adhesive polymer contains a non-volatile compound having a good affinity with a resist material and having at least one unsaturated double bond in the molecule. An adhesive sheet made of a pressure sensitive adhesive is preferably used. Here, having a good affinity with the resist material means that the phenomenon of dissolving, swelling or destroying the resist material is remarkable, and also includes the phenomenon of migration or diffusion into the resist material. As a guide for this, the resist material is sufficiently dried and the solvent is dipped in the non-volatile compound, and the resist material is dissolved, swelled or destroyed when stored at 130 ° C. for 24 hours. Further, that the compound is non-volatile means that it is not easily volatilized in the step of coating and drying the adhesive.

Such a non-volatile compound has a function such that after the adhesive sheets are adhered on the semiconductor substrate on which the resist film image is present, the resist material and the adhesive are integrated by the action of this compound and then cured. . Therefore, this non-volatile compound is required to have at least one unsaturated double bond capable of being cured by heat or light in the molecule and to have good affinity with the resist material. It is also required that the polymer has good compatibility with the water-soluble polymer and does not flow out during storage.

Examples of such non-volatile compounds include phenoxy polyethylene glycol (meth) acrylate, ε-caprolactone (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate and trimethylolpropane tri. (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, oligoester (meth) acrylate, and the like. Among these, the type of pressure-sensitive adhesive polymer to be used. One or two or more of them can be appropriately selected and used depending on the target resist material.

The amount of the non-volatile compound used is usually 5 to 20 relative to 100 parts by weight of the pressure-sensitive adhesive polymer.
The amount is 0 parts by weight, preferably 10 to 100 parts by weight. If the amount used is too small, the peeling effect of the resist material may not be sufficient, and if it is too large, the adhesive may flow out during storage, which is not preferable.

In the above-mentioned curable pressure-sensitive adhesive used in the present invention, it is preferable that the pressure-sensitive adhesive polymer is cross-linked to enhance cohesive force in terms of workability when it is attached to a semiconductor substrate. . For example, an acrylic polymer obtained by copolymerizing a carboxyl group- or hydroxyl group-containing monomer as a pressure-sensitive adhesive polymer is used, and a polyfunctional compound that reacts with the functional group of the polymer, such as polyisocyanate, polyepoxy, various metal salts, By containing a chelate compound or the like in the adhesive, the above reaction can be promoted in the step of forming a sheet or the like to crosslink the polymer.

The amount of the polyfunctional compound used is usually 20 parts by weight or less based on 100 parts by weight of the pressure-sensitive adhesive polymer. Within this range, the higher the molecular weight of the polymer, the lower the molecular weight of the polymer. , May be selected as appropriate.
If the amount of the polyfunctional compound used is too large, the adhesive strength will decrease, which is not preferable.

The curable pressure-sensitive adhesive may also contain a filler such as finely divided silica for the same purpose as the use of the above polyfunctional compound. Further, various additives such as a tackifier, a colorant and an anti-aging agent may be contained if necessary. The amount of these used may be in the usual range.

To the curable pressure-sensitive adhesive which can contain such various components, a polymerization initiator suitable for the curing means can be further added. For example, in the case of heat curing, benzoyl peroxide, a thermal polymerization initiator such as azobisisobutyronitrile that generates radicals by heating is used, and in the case of photocuring such as ultraviolet light, benzoin, benzoin ethyl ether, A photopolymerization initiator that generates radicals by light irradiation such as dibenzyl is used. These polymerization initiators are usually used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive polymer.

The curable pressure-sensitive adhesive used in the present invention thus constructed has an initial elastic modulus, that is, an elastic modulus before curing of usually about 0.5 to 50 g / mm ² , and after curing. It is desirable that the elastic modulus is adjusted to about 3 to 400 g / mm ² . This is because when the elastic modulus is adjusted to such a range, favorable results can be obtained for both the pressure-sensitive adhesive property before curing and the resist releasability after curing. The adjustment of the elastic modulus is carried out by the type of pressure-sensitive adhesive polymer, the amount of the non-volatile compound added to the polymer, the amount of other compounding components, and the like,
Alternatively, it can be carried out by appropriately selecting the degree of crosslinking by the polyfunctional compound, the curing conditions and the like.

The above-mentioned elastic modulus was determined by applying a stress-strain to the adhesive having a cross-sectional area of 5 mm ² under a temperature of 23 ± 2 ° C. at a pulling speed of 50 mm / min with a marked line distance of 10 mm. It means a value measured by a method of obtaining a curve and obtaining it from an initial slope.

When used, such a curable pressure-sensitive adhesive can be formed into a sheet or tape by itself, but it is usually dried on a film substrate. To be about 10 to 180 μm, which can be used as an adhesive sheet used in the method for removing a resist film image of the present invention. As the film substrate, for example, a resin film made of polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polyvinyl chloride, a saponified product of ethylene-vinyl acetate copolymer, and having a thickness of usually about 12 to 100 μm is used. In particular, when the adhesive is cured by light irradiation, a material that transmits light such as ultraviolet rays is selected and used.

In the method for removing a resist film image according to the present invention, an adhesive sheet using the curable pressure-sensitive adhesive having the above-mentioned structure is attached onto a semiconductor substrate having a resist film image, and the resist material and the adhesive are used. After the two are integrated, a predetermined curing treatment is performed by heating or light irradiation. At this time, when the thermal influence on the semiconductor substrate is taken into consideration, the curing treatment by light irradiation is particularly suitable, and the irradiation amount of ultraviolet rays is usually in the range of 300 to 3000 mj / cm ² .

By this curing treatment, the adhesive is cured in a state of being integrated with the resist material, and the elastic modulus thereof is remarkably increased as described above, and accordingly, the adhesive force between the resist film image and the semiconductor substrate is increased. Greatly reduced. As a result, by peeling off the adhesive sheets after the curing, the resist film image on the substrate is integrated with the adhesive sheets,
Can be removed easily and completely.

The third substance having a function of facilitating the removal of the resist film image in the present invention is an amine compound solution. The amine compound is not particularly limited, and primary, secondary, and tertiary amines can be used. Further, lower and water-soluble amine compounds are preferable, but higher and solid amine compounds can be used as long as they are soluble in a solvent.

Specific examples of this amine compound include, for example, tertiary amines such as trioctylamine and triethanolamine, secondary amines such as diisooctylamine and diethanolamine, stearylamine, aminonaphthol, 2- Aminopropyl alcohol, m-xylylenediamine, 2-aminoethanol, 2-amino-
Other examples include primary amines such as 2-ethyl-1,3-propanediol, amine polymers such as polyethyleneimine and triethylenetetramine, and those having a primary to tertiary amino group. Among these, one kind or two or more kinds can be appropriately selected and used according to the resist material to be targeted.

The method of bringing the solution of the amine compound into contact with the resist film image is not particularly limited.
Spraying of the solution or immersion in the solution can be adopted.

In the present invention, after carrying out the above-mentioned contact treatment, preferably after removing the water adhering to the image surface of the resist film by a normal drying means such as spraying with dry N ₂ , adhesive sheets And the adhesive material and the resist material are integrally peeled off. At this time, the ion-implanted resist film image can be satisfactorily removed from the semiconductor substrate by bringing the amine compound into contact with the resist film image.

The adhesive sheets used here are not limited in any way, and ordinary pressure-sensitive adhesive sheets can be used. In particular, from the viewpoint of preventing the contamination of the semiconductor substrate, the adhesive sheet particularly has an affinity with the resist agent. It is preferable to attach adhesive sheets using a good curable pressure-sensitive adhesive. As the adhesive sheet using such a curable pressure-sensitive adhesive, the same ones as described above can be used.

[0041]

As described above, according to the present invention, an image of a resist film on a semiconductor substrate, into which ions which are usually difficult to remove are implanted, can be removed very easily and reliably, and further, the image in the resist material can be removed. This has the effect of reducing the problem that the impurity ions are injected into the semiconductor substrate.

[0042]

EXAMPLES The present invention will be described below based on examples. In addition, "parts" means "parts by weight".

Reference Example 1 A resist material consisting of cresol novolac resin and naphthoquinone diazide was applied on the surface of a silicon wafer (semiconductor substrate), heated, exposed and developed to form a resist film image on the entire surface. ⁺ Ion acceleration energy 8
The entire surface was implanted at a high concentration of 0 keV and a dose amount of 1 × 10 ¹⁶ ions / cm ² .

Example 1 A silicon wafer that had been ion-implanted according to the reference example was immersed in boiled (100 ° C.) ultrapure water for 10 seconds, and then the water content on the resist film image surface was blown off with N ₂ gas to clean the surface. Dried. Next, a curable pressure-sensitive adhesive sheet containing an acrylic polymer as a main component was pressure-bonded to the entire surface of the resist film image on a heating plate of 100 ° C., and then ultraviolet rays of 1000 mJ were applied by a high pressure mercury lamp. It was irradiated and cured at an irradiation dose of / cm ² . Then, when the adhesive sheet was peeled off, the resist film image was peeled off together with the adhesive sheet. The surface of the silicon wafer was observed with a fluorescence microscope, but no resist material was observed.

Example 2 An adhesive sheet was prepared in the same manner as in Example 1 except that shower-like boiled ultrapure water was sprayed for 10 seconds instead of being immersed in boiled ultrapure water. Was peeled off, the resist film image was peeled off together with the adhesive sheet. The surface of the silicon wafer was observed with a fluorescence microscope, but no resist material was observed.

Comparative Example 1 A peeling removal process was performed in the same manner as in Example 1 except that the pretreatment with ultrapure water was not carried out. Only the adhesive sheet was peeled off, and the resist film image remained entirely on the silicon wafer. Was there.

Production Example 1 of adhesive sheet 80 parts of n-butyl acrylate, 15 parts of ethyl acrylate
Part of the monomer mixture consisting of 5 parts of acrylic acid and 150 parts of ethyl acetate and 0.1 part of azobisisobutyronitrile were subjected to solution polymerization at 60 ° C. for 12 hours under a nitrogen stream to give a weight average molecular weight of 56. The glass transition point is 231 °
An acrylic polymer solution of K was obtained.

To 250 parts of this acrylic polymer solution,
100 parts of urethane acrylate as a non-volatile compound,
3 parts of diphenylmethane diisocyanate as a polyfunctional compound and 3 parts of benzyl dimethyl ketal as a polymerization initiator
The parts were uniformly mixed to obtain a curable pressure-sensitive adhesive solution.

Next, the curable pressure-sensitive adhesive solution was added to
A resist film image-removing adhesive sheet used in the present invention was produced by coating a polyester film having a thickness of 50 μm so that the thickness after drying was 50 μm, and drying at 150 ° C. for 10 minutes.

Production Example 2 of Adhesive Sheet A monomer mixture consisting of 60 parts of 2-ethylhexyl acrylate, 30 parts of butyl acrylate, 5 parts of vinyl acetate and 5 parts of acrylic acid was polymerized in the same manner as in Production Example 1 to obtain a weight average. An acrylic polymer solution having a molecular weight of 620,000 and a glass transition point of 207 ° K was obtained.

To 250 parts of this acrylic polymer solution,
Oligoester acrylate 10 as non-volatile compound
The present invention was carried out in the same manner as in Production Example 1 by uniformly mixing 0 parts, 3 parts of tolylene diisocyanate as a polyfunctional compound, and 5 parts of benzyl dimethyl ketal as a polymerization initiator to obtain a curable pressure-sensitive adhesive solution. An adhesive sheet for removing the resist film image used in 1. was prepared.

Production Example 3 of Adhesive Sheet 3 parts of diphenylmethane diisocyanate were uniformly mixed with 250 parts of the solution of the acrylic polymer of Production Example 1,
After preparing the pressure-sensitive adhesive solution, an adhesive sheet for removing a resist film image was prepared in the same manner as in Production Example 1.

Example 3 The ion-implanted silicon wafer in the reference example was
After soaking in methyl alcohol for 1 minute, the methyl alcohol content on the resist film image surface is blown off with N ₂ gas,
The surface was dried. Next, after the adhesive sheets obtained in Production Examples 1 and 2 were pressure-bonded to the entire surface of the resist film image on a heating plate at 100 ° C., ultraviolet rays of 1000 mJ / cm ² were applied by a high pressure mercury lamp. The adhesive sheet was cured by irradiating with an irradiation amount. After that, when the adhesive sheet was peeled off, the resist film image was peeled off together with the adhesive sheet. The surface of the silicon wafer was observed with a fluorescence microscope, but no resist material was observed.

Comparative Example 2 A peeling treatment was carried out in the same manner as in Example 3 except that the adhesive sheet obtained in Production Example 3 was used. Only the adhesive sheet was peeled off, and the resist film image was formed on the silicon wafer. It remained all over.

Example 4 A resist film image was formed in the same manner as in Example 3 except that shower-like methyl alcohol was sprayed for 1 minute instead of immersion in methyl alcohol for 1 minute. When peeling and removing treatment was performed, good results were obtained as in Example 3.

Example 5 When the resist film image was peeled off in the same manner as in Example 3 except that methyl alcohol was changed to ethyl alcohol, good results were obtained as in Example 3. was gotten.

Comparative Example 3 The resist film image was peeled and removed in the same manner as in Example 3 except that methyl alcohol was changed to isobutyl alcohol. As a result, almost only the adhesive sheet was peeled off, and the resist film was removed. The image was largely left on the silicon wafer.

Comparative Example 4 The resist film image was peeled and removed in the same manner as in Example 3 except that the pretreatment with the water-affinity compound solution was not carried out. Only the adhesive sheet was peeled off, and the resist film image was silicon. It was left on the entire surface of the wafer.

Example 6 A silicon wafer, which was subjected to ion implantation in the reference example, was
After dipping in 2-aminoethanol for 10 minutes, the 2-aminoethanol content on the resist film image surface was blown off with N ₂ gas to dry the surface. Next, Production Examples 1 and 2
Adhesive sheet obtained in, on the entire surface of the resist film image,
After sticking by pressure bonding on a heating plate at 100 ° C., ultraviolet rays were irradiated by a high pressure mercury lamp at an irradiation dose of 1000 mJ / cm ² to cure the adhesive sheet. After that, when the adhesive sheet was peeled off, the resist film image was peeled off together with the adhesive sheet. The surface of the silicon wafer was observed with a fluorescence microscope, but no resist material was observed.

Comparative Example 5 When a peeling removal treatment was performed in the same manner as in Example 6 except that the adhesive sheet obtained in Production Example 3 was used, almost only the adhesive sheet was peeled off, and the resist film image was on the silicon wafer. Most of it remained.

Example 7 In the same manner as in Example 6, except that shower-like 2-aminoethanol was sprayed for 10 minutes instead of dipping in 2-aminoethanol for 10 minutes. When the resist film image was peeled and removed, good results were obtained as in Example 6.

Example 8 A peeling removal treatment of a resist film image was carried out in the same manner as in Example 6 except that 2-aminoethanol was changed to 2-amino-2-ethyl-1,3-propanediol. Then, good results were obtained as in Example 6.

Comparative Example 6 When the resist film image was peeled and removed in the same manner as in Example 6 except that the pretreatment with an amine compound was not carried out, only the adhesive sheet was peeled off, and the resist film image was formed on the silicon wafer. Was completely left over.

Reference Example 2 A positive type photoresist material consisting of cresol novolac resin, naphthoquinone diazide sulfonic acid ester of polyhydroxyl compound and ethyl lactate was applied on the surface of a silicon wafer (semiconductor substrate), heated, exposed and developed. After forming a resist film image on the entire surface, As ⁺ ions are accelerated at an energy of 80 keV and a dose of 1 × 10 ¹⁶ ions / cm ²
Was injected over the entire surface at a high concentration of.

Example 9 Water vapor of ultrapure water was added to the resist film image of Reference Example 2 described above.
After spraying for minutes, the moisture on the resist film image surface was blown off with dry nitrogen, and then a general pressure-sensitive adhesive sheet was stuck on the entire surface of the resist film image at room temperature. After that, when the adhesive sheet was peeled off, the resist film image was peeled off together with the adhesive sheet.

Comparative Example 7 A peeling removal process was performed in the same manner as in Example 9 except that the pretreatment was not performed in Example 9, and only the adhesive sheet was peeled off, and the resist film image remained on the entire surface of the silicon wafer. It was

Adhesive Sheet Production Example 4 The curable pressure-sensitive adhesive solution obtained in Adhesive Sheet Production Example 1 was applied onto a polyester film having a thickness of 50 μm so that the thickness after drying would be 50 μm. 24 at 70 ℃
After drying for a minute, an adhesive sheet for removing a resist film image used in the present invention was produced.

Example 10 Water vapor of ultrapure water was added to the resist film image of Reference Example 2 described above.
After spraying for minutes, the moisture on the surface of the resist film image was blown off with dry nitrogen, and then the adhesive sheet obtained in the above Production Example 4 was stuck on the entire surface of the resist film image at room temperature and then irradiated with ultraviolet rays of 1000 mJ / cm 2 by a high pressure mercury lamp. ^It was irradiated and cured at a dose of ² . Then, when the adhesive sheet was peeled off, the resist film image was peeled off together with the adhesive sheet. The surface of the silicon wafer was observed with a fluorescence microscope, but no resist material was observed.

Example 11 A resist film was prepared in the same manner as in Example 10 except that the steam of ultrapure water was sprayed for 5 minutes instead of being left in a steam atmosphere of methyl alcohol for 10 minutes. When the image removal processing was performed, the same good results as in Example 10 were obtained.

[Measurement of Elastic Modulus] The initial elastic modulus of the pressure-sensitive adhesive of the adhesive sheet obtained in each Production Example and ultraviolet rays were irradiated at a dose of 1000 mj / cm ² using a high pressure mercury lamp to cure. As a result of measuring the elastic modulus after the test, it was as shown in Table 1 below.

[0071]

[Table 1]

Front page continuation (72) Inventor Kaoru Aizawa 1-2-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation (72) Hideaki Shimodan 1-2-2 Shihohozumi, Ibaraki-shi, Osaka Nitto Denko Stock In-house (72) Inventor Jun Nakazawa 1-2 1-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation

Claims (10)

[Claims] 1. In a method of removing an image made of a resist material existing on a semiconductor substrate, a substance having a function of facilitating the removal of the image is brought into contact with the resist film image as a pretreatment, and then the resist film image is obtained. A method for removing a resist film image, which comprises: sticking adhesive sheets on top of the adhesive sheet and peeling the adhesive sheet and the resist material together. 2. The method for removing a resist film image according to claim 1, wherein the contact treatment of the substance having a function of facilitating the removal of the image is spraying of the substance with a solution or immersion in the solution. . 3. The resist film according to claim 1, wherein the contact treatment of the substance having a function of facilitating the removal of the image is spraying of a vaporized substance or leaving it in an atmosphere of vaporization. Image removal method. 4. The method of removing a resist film image according to claim 1, wherein the substance having a function of facilitating image removal is ultrapure water or pure water. 5. The method for removing a resist film image according to claim 3, wherein the substance having a function of facilitating image removal is ultrapure water or pure water. 6. A substance having a function of facilitating image removal is a water-affinity compound.
The method for removing a resist film image described. 7. The water-affinity compound is selected from at least one of alcohols, ketones, and esters having a boiling point of 98 ° C. or lower and an alkyl group having 3 or less carbon atoms. Of removing the resist film image of. 8. The method for removing a resist film image according to claim 1, wherein the substance having a function of facilitating image removal is an amine compound solution. 9. A method for removing a resist film image, wherein the adhesive sheet used in the method for removing a resist film image according to claim 1 is an adhesive sheet using a curable pressure-sensitive adhesive. . 10. A curable pressure-sensitive adhesive comprising a pressure-sensitive adhesive polymer containing a non-volatile compound having good affinity with a resist material and having at least one unsaturated double bond in the molecule. 10. The method for removing a resist film image according to claim 9, wherein