JP4518067B2 - Resist material - Google Patents

Description

  The present invention relates to a resist material for fine patterning that reduces a pattern separation size or a hole opening size when forming a resist pattern in a semiconductor process. The resist material of the present invention is described as the second resist in this specification.

  Along with the high integration of semiconductor devices, the wiring and isolation width required for the manufacturing process have become very fine. In general, a fine pattern is formed by a method in which a resist pattern is formed by a photolithography technique and various underlying thin films are etched using the formed resist pattern as a mask.

  Therefore, the photolithography technique is very important in forming a fine pattern. The photolithography technique is composed of resist coating, mask alignment, exposure, and development, and there is a limit to miniaturization due to restrictions on the exposure wavelength.

  Therefore, as a method for forming a fine resist pattern that exceeds the limit of photolithography technology by conventional exposure, a technique using mutual diffusion of resin components of the first resist and the second resist is disclosed (for example, Patent Documents). 1 and 2).

JP-A-6-250379 (first page) Japanese Patent Laid-Open No. 7-134422 (first page)

  However, a photoresist material soluble in an organic solvent that can dissolve the first resist is used as the second resist, and there is a problem that the first resist pattern is deformed.

  In addition, a processing method for removing the second resist includes a developer (an alkaline developer such as a tetramethylammonium hydrate aqueous solution or the like) that can expose the second resist, generate an acid, and dissolve the second resist. The second resist is dissolved and removed using xylene or the like. However, when the second resist is exposed, it may be solubilized by exposing the first resist which is the base. Since the solubilized first resist is soluble in a solution capable of dissolving the second resist, there is a high possibility that the first resist is dissolved when the second resist is dissolved and removed. There was a problem that the margin was small.

In addition, when polyvinyl alcohol is used as the second resist, its effect is small, the pattern shape after processing is poor, and development is performed only with water, so that sufficient cleaning is not performed and the pattern is not patterned. However, there is a problem that a development residue such as a stain is likely to remain, and pattern defects are generated during etching in the next process.
As described above, it has been difficult to form a fine resist pattern exceeding the wavelength limit by the conventional photolithography technique using exposure.
Further, although a technique that enables pattern formation exceeding the wavelength limit has been proposed, some problems remain and it is difficult to apply to actual semiconductor manufacturing.

  The present invention has been made to solve such a problem, and for fine patterning for realizing fine separation resist pattern formation that enables formation of a pattern exceeding the wavelength limit in making the separation pattern and hole pattern finer. A resist material is to be provided. Furthermore, the selection range of the base resin is expanded by using a material that is soluble in an organic solvent.

The first resist material according to the present invention is provided on the first resist pattern on the substrate, does not dissolve the first resist pattern, and causes a crosslinking reaction with an acid so as to come into contact with the first resist pattern. A resist material that is developed with a developer that forms a crosslinked layer at the interface portion and develops the non-crosslinked portion, and is an unsaturated polyester that is soluble in an organic solvent and water is a poor solvent, polymethyl methacrylate, polyimide, Any of urethane resin, phenol resin, cellulose resin, maleic acid resin, epoxy resin, and mixed resin of polyvinyl methyl silsesquioxane resin and polyvinyl siloxane resin, and guanidine, thiazole, thiuram, dithioicarbamate Organic accelerator, isocyanate, polyfunctional epoxy, polyfunctional acrylic resin, polyfunctional silicone Tan, is characterized in that it comprises at least one monomer or oligomer of a polyfunctional silicone resin.

  According to the present invention, it is possible to form a pattern that exceeds the wavelength limit.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a mask pattern for forming a finely separated resist pattern targeted by the present invention. Examples of the mask pattern are shown in (a) to (f). That is, (a) is a fine hole mask pattern 100, (b) is a fine square pattern 200, (c) is a fine space mask pattern 300, (d) is an isolated pattern 400, (e) is An isolated residual pattern 500, (f) shows an isolated residual pattern 600. 2 and 3 are process flow diagrams for explaining the finely divided resist pattern forming method of the first embodiment using the resist material of the present invention.

First, a method for forming a fine separation resist pattern according to this embodiment and a method for manufacturing a semiconductor device using the same will be described with reference to FIGS.
As shown in FIG. 2A, a first resist 1 having a mechanism for generating an acid therein is applied to a semiconductor substrate (semiconductor wafer) 3 by light irradiation or heat treatment (for example, a thickness of 0.7). ˜1.0 μm).
The first resist 1 is applied on a semiconductor substrate by spin coating or the like, and then pre-baked (heat treatment at 70 to 120 ° C. for about 1 minute) to evaporate the solvent in the first resist. Let

  Next, in order to form the first resist pattern, the sensitivity wavelength of the first resist used, such as g-line, i-line, Deep-UV, KrF excimer, ArF excimer, EB (electron beam) or X-ray, is used. Projection exposure is performed using a light source corresponding to the above and using a mask including a pattern as shown in FIG.

The first resist used here is not particularly limited, and may be any resist that uses a mechanism that generates an acidic component inside the resist by heat treatment or irradiation with light, for example, KrF excimer, ArF. Any resist may be used as long as it generates acid upon irradiation with excimer, EB (electron beam), X-ray or the like, and either a positive type or a negative type resist may be used.
For example, examples of the first resist include a positive resist composed of a novolak resin and a naphthoquinonediazide-based photosensitizer.
Furthermore, as the first resist, a chemically amplified resist using a mechanism that generates an acid upon exposure can be applied. The resist is not particularly limited as long as it is a resist material that uses a reaction system that generates an acid upon exposure. Never happen.

After the exposure of the first resist as described above, PEB (post-exposure heating) is performed as needed (for example, PEB temperature: 50 to 130 ° C.) to develop the resist resolution.
Next, it develops using about 0.05-3.0 wt% alkaline water bath liquid, such as TMAH (tetramethylammonium hydroxide). FIG. 2B shows the pattern of the first resist 1 formed in this way.
After performing the development processing, if necessary, for example, post-development baking may be performed at a baking temperature of 60 to 120 ° C. for about 60 to 90 seconds.
Since this heat treatment affects the subsequent mixing reaction, it is desirable to set the temperature appropriately in accordance with the first resist or the second resist material to be used.
The process described above is the same as the formation of a resist pattern by a general resist process, except that the first resist 1 that generates an acid is used.

As described above, after forming the pattern 1a of FIG. 2B, as shown in FIG. 2C, the second resist material that crosslinks in the presence of an acid is dissolved in a solvent that does not dissolve the first resist 1. Then, it is applied to the first resist pattern 1 a on the semiconductor substrate 3.
The method of applying the second resist material is not particularly limited as long as it can be uniformly applied onto the first resist pattern 1a, and is applied by spraying or dipped in the second resist solution. It is also possible to apply by.
Next, after the application of the second resist 2, as shown in FIG. 2 (d), this is pre-baked (for example, at about 85 ° C. for about 60 seconds) to form the second resist layer 2. .

Next, as shown in FIG. 2 (e), the semiconductor substrate 3 is heat-treated (60 to 130 ° C., hereinafter abbreviated as “mixing bake: MB”) to diffuse the acid from the first resist pattern 1a. Then, a crosslinking reaction is generated at the interface between the second resist 2 and the first resist pattern 1a. A crosslinked layer 4 that has undergone a crosslinking reaction so as to cover the first resist pattern 1 a with the MB is formed in the second resist 2.
The MB temperature / time in this case is 60 to 130 ° C./60 to 120 sec, and it may be set to an optimum condition depending on the type of resist material to be used and the required thickness of the reaction layer.
In addition, the thickness of the cross-linked layer can be controlled by adjusting the time for heating and cross-linking (MB time), which is a highly reactive control method.

  Next, as shown in FIG. 2F, the second resist 2 that has not been cross-linked is developed and peeled off without dissolving the first resist pattern using a developer. By the above processing, it is possible to obtain a resist pattern in which the hole inner diameter or separation width is reduced or the area of the isolated pattern is enlarged.

In the manufacturing method described above with reference to FIG. 2, after the second resist layer is formed on the first resist pattern, the first resist pattern 1a is transferred from the first resist pattern 1a to the second resist by an appropriate heat treatment. A method for generating an acid that diffuses an acid has been described.
An appropriate material having high reactivity is selected as the second resist, and an appropriate heat treatment (for example, 85 ° C. to 150 ° C.) is performed, so that no exposure for acid generation occurs in the first resist pattern. It is possible to obtain a resist pattern in which the interface between the resists causes a cross-linking reaction due to the diffusion of the acid present in the resist, the hole inner diameter or the separation width is reduced, or the area of the isolated pattern is enlarged.

  Using the fine separation resist pattern formed on the first resist pattern 1a as a mask as described above, various underlying thin films are etched to form fine spaces or fine holes in the underlying thin film, thereby manufacturing a semiconductor device.

Next, a method of generating and diffusing an acid by exposure instead of heat treatment or prior to heat treatment will be described.
FIG. 3 is a process flow diagram for explaining the fine resist pattern forming method in this case. First, FIGS. 3A and 3B are the same as FIGS. 2A and 2B, and thus description thereof is omitted.

After forming the second resist layer as described above, as shown in FIG. 3C, the entire surface of the semiconductor substrate is again exposed with the g-line or i-line of the Hg lamp to generate an acid in the first resist. Let
The light source used for the exposure at this time can be an Hg lamp, a KrF excimer, an ArF excimer, or the like depending on the photosensitive wavelength of the first resist, and is particularly limited as long as acid can be generated by exposure. What is necessary is just to expose using the light source and exposure amount according to the photosensitive wavelength of the used 1st resist instead of what.
The exposure process for generating an acid component in the first resist pattern is performed when the applied first resist and second resist have relatively low reactivity, or the required thickness of the crosslinked layer is relatively thick. Although it is desirable to apply in cases or when it is desired to selectively form a crosslinked layer, it is not particularly limited and may be used as appropriate.

  As described above, in the example of FIG. 3, the exposure is performed after the application of the second resist to generate an acid in the first resist, and the first resist 1 is covered with the second resist 2. Since the amount of acid generated in the first resist 1 can be accurately controlled over a wide range by adjusting the exposure amount, the film thickness of the reaction layer 4 can be accurately controlled.

  As described above, a semiconductor device can be manufactured by etching various underlying thin films using the formed fine separation resist pattern as a mask to form fine spaces or fine holes in the underlying thin film.

  In the above example, the method for forming a fine resist pattern on the entire surface of the semiconductor substrate 3 has been described. Next, a method for selectively forming a fine resist pattern only in a desired region of the semiconductor substrate 3 will be described. FIG. 4 is a process flow diagram of the manufacturing method in this case.

  That is, as shown in FIG. 4, in addition to exposing the semiconductor substrate 3 on which the second resist is formed on the first resist pattern, it is also possible to selectively expose only a predetermined portion necessary. In this case, it is possible to distinguish between a region where the second resist is crosslinked at the interface with the first resist pattern and a region where the second resist is not crosslinked. In this way, by using an appropriate exposure mask, the semiconductor substrate is selectively exposed to distinguish between the exposed portion and the unexposed portion, and the second resist pattern is at the boundary portion with the first resist pattern. A region that crosslinks and a region that does not crosslink can be formed. Thereby, fine holes or fine spaces having different dimensions can be formed on the same semiconductor substrate.

  The steps of FIGS. 4A and 4B are the same as the steps of FIGS. 3A and 3B. As shown in FIG. 4B, after forming the second resist 2 layer, a part of the semiconductor substrate 3 was shielded by the light shielding plate 5 and selected as shown in FIG. 4C. The region is exposed again to generate acid in the first resist pattern 1a. As a result, as shown in FIG. 4D, a crosslinked layer 4 is formed at the interface of the second resist 2 in contact with the first resist pattern 1a in the exposed portion.

Next, the second resist material will be described.
As the second resist material, a single type or a mixture of two or more types of resins (crosslinkable resins) that are soluble in an organic solvent that has an unsaturated bond or a hydroxyl group and crosslinks with an acid, or are soluble in an organic solvent. A solution containing a resin soluble in an organic solvent that is cross-linked by this cross-linking agent in the presence of a cross-linking agent and an acid is used, for example, as a solution in a solvent.
The resin cross-linked by the cross-linking agent may be the above cross-linkable resin, but is not limited thereto, and any resin that is cross-linked by the cross-linking agent in the presence of an acid may be used.
As a second resist forming method, the solution is formed by spin coating, dipping in the solution or spray coating.
When a resin mixture is used as the second resist, the material composition is not particularly limited as long as an optimal composition is set depending on the first resist material to be applied or the set reaction conditions. .

That is, the material applied to the second resist is particularly limited as long as it is a material that is soluble in a solvent that does not dissolve the first resist pattern 1a and that causes a crosslinking reaction in the presence of an acid component. is not.
The second resist that causes a crosslinking reaction in the presence of an acid includes a case where the resist material itself is a crosslinkable compound. Further, the second resist that causes a crosslinking reaction in the presence of an acid is a resist material. And the case where a compound as a crosslinking agent and a crosslinking compound as a crosslinking agent are mixed.

The resin soluble in the organic solvent, unsaturated polyesters, polymethyl methacrylate, polyimide, urethane resins, phenol resins, cellulose scan resins, maleic acid resins, epoxy resins and the like, one or more kinds thereof mixtures of, or Ru using a salt thereof.

The resin used for the second resist material may be used as one or a mixture of two or more of the above resins, and can be appropriately adjusted depending on the reaction amount with the underlying resist, reaction conditions, and the like. These resins may be used in the form of a salt such as hydrochloride for the purpose of improving the solubility in a solvent.
In particular, when the crosslinking reaction under the acidic component of the resin does not occur or is low, a crosslinking agent can be further mixed with these resins.

  The crosslinking agent soluble in the organic solvent can crosslink the resins by heat treatment or light irradiation in the presence of an acid and insolubilize the resin in the organic solvent. For example, guanidine, thiazole, thiuram Or dithioicarbamate organic accelerator, melamine derivative, urea derivative, benzoguanamine, glycoluril, isocyanate, polyfunctional epoxy, polyfunctional acrylic resin, polyfunctional urethane, polyfunctional silicone resin monomer or oligomer 1 A type or a mixture of two or more types is used. The crosslinking agent soluble in these organic solvents is not limited to the above, and any crosslinking agent can be used as long as it does not mix with or dissolve in the first resist and can cure the resist by supplying an acid.

In addition, the solvent used for the second resist material and the solvent for peeling (developing) the second resist sufficiently dissolve the constituent resin and the crosslinking agent, and do not dissolve the first resist. The above mixed solvent is used.
Examples of the solvent include alcohols, ketones, ethers, esters, halogenated hydrocarbons, benzenes, alkoxybenzenes, cyclic ketones, and the like, such as toluene, xylene, methoxybenzene, ethoxybenzene, benzene, pyridine, Cyclohexane, dioxane, methyl ethyl ketone, methyl isobutyl ketone, acetone, t-butyl acetate, n-butyl acetate, ethyl acetate, tetrahydrofuran, diethyl ether, isopropyl ether, methyl cellosolve, ethyl cellosolve, N-methylpyrrolidone, N, N'-dimethyl Formamide, ethanol, methanol, isopropanol, butyl alcohol, ethylene glycol, ethylbenzene, diethylbenzene, n-butyl ether, n-hexane, n-heptane, methoxy Benzene, ethoxybenzene, phenetol, veratrol, γ-butyrolactone, chloroform and the like. These solvents can be used alone or in accordance with the solubility of the material used for the second resist. May be mixed within a range not dissolving the first resist pattern.

In the present invention, it is important to control the crosslinking reaction between the first resist and the second resist and to control the thickness of the crosslinked layer formed on the first resist pattern.
The control of the crosslinking reaction can be optimized according to the reactivity between the first resist and the second resist to which the present invention is applied, the shape of the first resist pattern, the thickness of the required crosslinking reaction layer, and the like. desirable.

Control of the crosslinking reaction between the first resist and the second resist includes a method by adjusting process conditions and a method by adjusting the composition of the second resist material.
As a process control method of the crosslinking reaction,
(1) adjusting the exposure amount to the first resist pattern;
(2) Adjust mixing bake (MB) temperature and processing time.
From the aspect of the material composition used for the second resist,
(3) Mix two or more types of suitable resins and adjust the mixing ratio.
(4) The resin is mixed with an appropriate crosslinking agent, and the mixing ratio is adjusted.
Such a method is effective.

However, the control of these cross-linking reactions is not determined centrally, and (1) reactivity with the first resist material to be applied,
(2) First resist pattern shape, film thickness,
(3) Required film thickness of the crosslinking agent layer,
(4) Usable exposure conditions or MB conditions,
(5) It is necessary to determine in consideration of various conditions such as coating conditions.
In particular, it has been found that the reactivity between the first resist and the second resist is affected by the composition of the first resist material. Therefore, when the present invention is actually applied, the above-mentioned is described. It is desirable to optimize the second resist material composition in consideration of factors.
Accordingly, the type of material used for the second resist and the composition ratio thereof are not particularly limited, and are optimized and used according to the type of material used, heat treatment conditions, and the like.

Further, according to the present invention, as described above, the fine separation resist pattern is formed on the semiconductor substrate 3, but this may be formed on an insulating layer such as a silicon oxide film according to the manufacturing process of the semiconductor device. It may also be formed on a conductive layer such as a poly-silicone film.
The present invention is not particularly limited to the base film, and can be applied in any case as long as it is on a substrate on which a resist pattern can be formed, and is formed on a substrate as necessary. is there.

  Further, in the present invention, before forming the second resist film on the first resist pattern, the first resist pattern is heat-treated to control the solvent resistance of the second resist to the solvent and the developer. By doing so, the margin of the development conditions of the second resist can be widened, and the shape of the resulting fine pattern or fine space can be improved. The heat treatment temperature of the first resist pattern may be equal to or lower than the thermal decomposition temperature of the resist to be used. In particular, the heat treatment temperature is preferably in a range of 60 ° C. to 150 ° C.

Further, in the present invention, a concentration of 20 wt% or less is used with one or a mixture of two or more plasticizers soluble in an organic solvent as an additive for the purpose of imparting flexibility and elasticity to the second resist material. It is preferable to contain.
For example, phthalate esters such as dibutyl phthalate, dioctyl phthalate or butyl benzyl phthalate, phosphate esters such as tributyl phosphate, triphosfort or tricresyl phosphate, butyl ricinolate, dibutyl succinate or methylacetyl resealate Fatty acid ester series, butylphthalyl butyl glycolate, triethylene glycol, diethyl butyrate, polyethylene glycol, ethylene glycol, glycerin, propylene glycol, 3-methylenepentane-1,3,5-triol or triethylene glycol dibutyrate Glycol derivatives, sebacates such as dibutyl sebacate or dioctyl sebacate, epoxidized soybean oil, castor oil or chlorinated Paraffin and the like, but it is necessary that there is compatibility with the other of the second resist material.

In the present invention, the second resist material has an additive of one or more surfactant-soluble (oil-soluble) surfactants that are soluble in an organic solvent for the purpose of improving film-forming properties, and is 20 wt% or less. It is preferable to contain at a concentration of
The oil-soluble surfactant must be dissolved in the organic solvent used for the second resist, and if the second resist can be uniformly formed on the substrate with a small amount of addition, an anionic surfactant, a cation Any of surfactants, nonionic surfactants, amphoteric surfactants or fluorosurfactants may be used. For example, lecithin derivatives, propylene glycol fatty acid esters, glycerin fatty acid esters, polyoxyethylene glycerin fatty acid esters, polyglycerin. Fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbit fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene alkylphenol, polyoxyethylene alkylphenyl formaldehyde condensate Polyoxyethylene castor oil or hydrogenated castor oil, polyoxyethylene sterol or hydrogenated sterol, polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene lanolin Lanolin alcohol or beeswax derivative, polyoxyethylene alkylamine or fatty acid amide, polyoxyethylene alkyl ether phosphate or phosphate, alkyl ether carboxylate, alkyl phosphate and polyoxyethylene alkyl ether phosphate, alkylbenzene sulfone Acid salt, sulfonate, quaternary ammonium salt, alkylpyridinium salt, betaine acetate type amphoteric interface , Imidazoline type amphoteric surfactant, block polymerization type nonionic surfactant of ethylene oxide and propylene oxide, perfluoroalkyl sulfonate, perfluoroalkyl carboxylate, perfluoroalkyl polyoxyethylene ethanol, perfluoroalkyl Fluoroalkyl quaternary ammonium iodide or fluorinated alkyl ester can be mentioned.

  In the present invention, the dry etching resistance can be improved by combining a silicone resin as a resin composition soluble in the organic solvent used for the second resist.

  In the present invention, the reaction amount with the first resist can be controlled by adjusting the reactivity and introduction amount of the crosslinking site of the resin soluble in the organic solvent used for the second resist.

  In the present invention, the organic solvent-based developer is a mixture of a good solvent and a poor solvent of the second resist material, and fine adjustment of the developing speed is possible by adjusting the mixing ratio. Thus, the degree of reduction in the taper angle, resist pattern separation size or hole opening size after development is controlled.

  For example, an organic polar solvent is used as a good solvent, and water is used as a poor solvent to adjust the amount of water added.

  The semiconductor manufacturing apparatus of the present invention is manufactured by the above-described manufacturing method of each semiconductor device.

Embodiment 2. FIG.
FIG. 5 is a process flow diagram for explaining the finely divided resist pattern forming method of the second embodiment using the resist material of the present invention. With reference to FIGS. 1 and 5, a method for forming a finely separated resist pattern according to the second embodiment and a method for manufacturing a semiconductor device using the same will be described.

As shown in FIG. 5A, a first resist 11 containing a slight amount of acidic substance is applied to the semiconductor substrate 3. The first resist is pre-baked (heat treatment at 60 to 150 ° C. for about 1 minute), and then projected and exposed using a g-line or i-line of an Hg lamp and a mask having a pattern as shown in FIG. (It is omitted in 5).
Then, if necessary, heat treatment is performed with PEB (10 to 150 ° C.) to improve the resolution of the resist, and then development is performed using about 2.0% diluted water bath solution of TMAH (tetramethylammonium hydroxide).

Thereafter, post-development baking may be performed as necessary. Since this heat treatment affects the subsequent mixing reaction, it is necessary to set the temperature appropriately. FIG. 5B shows the first resist pattern 11 thus formed.
The process described above is the same as the formation of a resist pattern by a conventional resist process, except that a resist 11 containing an acid is used.

Next, after the pattern formation of FIG. 5B, as shown in FIG. 5C, the first resist 11 is dissolved on the semiconductor substrate (wafer) 3 including a crosslinkable product that crosslinks in the presence of an acid. A second resist 12 dissolved in a non-solvent is applied. As the solvent used here, the same material as that described in Embodiment Mode 1 is used.
Next, after the application of the second resist 12, it is pre-baked as necessary. Since this heat treatment affects the subsequent mixing reaction, it is desirable to set the temperature appropriately.

  Next, as shown in FIG. 5D, the semiconductor substrate 3 is heat-treated (60 to 150 ° C.), and the second resist 12 is formed by supplying acid from some acidic substances contained in the first resist 11. A crosslinking reaction is caused in the vicinity of the interface with the first resist. As a result, a crosslinked layer 14 that has undergone a crosslinking reaction so as to cover the first resist 11 is formed in the second resist 12.

  Next, as shown in FIG. 5E, the second resist 12 that has not been crosslinked is developed and peeled without dissolving the first resist pattern using a developer. By the above processing, it is possible to obtain a resist pattern with a reduced hole inner diameter or separation width.

  As described above, the first resist 11 according to the second embodiment does not need to generate an acid by exposure, and is adjusted so that the resist film 11 itself contains an acid. The acid is diffused by heat treatment. To crosslink. The acid contained in the first resist is preferably a carboxylic acid-based low molecular acid or the like, but is not particularly limited as long as it can be mixed with the resist solution.

Note that the first resist material and the second resist material reversed in the first embodiment can also be used in the second embodiment.
Further, the fine separation resist pattern 2a is formed on various semiconductor substrates, and a fine separation space or fine hole is formed on the semiconductor substrate using the fine separation resist pattern 2a as a mask. Same as 1.

Embodiment 3 FIG.
FIG. 6 is a process flow diagram for explaining the finely divided resist pattern forming method of the third embodiment using the resist material of the present invention. A method for forming a finely divided resist pattern according to the third embodiment and a method for manufacturing a semiconductor device using the same will be described with reference to FIGS.

First, as shown in FIG. 6A, a first resist 21 is applied to the semiconductor substrate 3. After pre-baking the first resist (heat treatment at 60 to 150 ° C. for about 1 minute), depending on the photosensitive wavelength of the first resist, for example, using the g-line or i-line of the Hg lamp, as shown in FIG. Projection exposure is performed using a mask including such a pattern (omitted in FIG. 6).
If necessary, heat treatment is performed with PEB (10 to 150 ° C.) to improve the resolution of the photoresist, and then development is performed using an about 2.0% diluted aqueous solution of TMAH (tetramethylammonium hydroxide). FIG. 6B shows the first resist pattern 21a thus formed.

  Thereafter, post-development baking may be performed as necessary. Since this heat treatment affects the subsequent mixing reaction, it is necessary to set the temperature appropriately. The above process is the same as the formation of a resist pattern by a conventional resist process.

After the pattern formation of FIG. 6B, as shown in FIG. 6C, the semiconductor substrate (wafer) 3 is immersed in an acidic solution. The processing method may be a normal paddle development method. Moreover, you may carry out by vaporization (spraying) of an acidic solution. In this case, the acidic solution may be either an organic acid or an inorganic acid. Specifically, for example, a low concentration of acetic acid is a suitable example.
In this step, the acid soaks in the vicinity of the interface of the first resist pattern 21a, and a thin layer containing the acid is formed. Thereafter, rinsing is performed using pure water as necessary.

Thereafter, as shown in FIG. 6E, the second resist dissolved in a solvent that contains a crosslinkable compound that crosslinks in the presence of an acid and does not dissolve the first resist 21 on the first resist pattern 21a. A resist 22 is applied.
As the second resist material and the solvent used here, the same materials as those described in Embodiment Mode 1 can be used.
Next, after the application of the second resist, the second resist 22 is pre-baked as necessary. Since this heat treatment affects the subsequent mixing reaction, it is set to an appropriate temperature.

  Next, as shown in FIG. 6F, the semiconductor substrate 3 is heat-treated (60 to 150 ° C.), mixed and baked, and the second resist 22 is formed by supplying acid from the first resist 21a. A crosslinking reaction is caused in the vicinity of the interface with the resist 1. As a result, the crosslinked layer 4 that has undergone a crosslinking reaction so as to cover the first resist 21 is formed in the second resist 22.

  Next, as shown in FIG. 6G, the second resist 22 that has not been crosslinked is developed and peeled without dissolving the first resist pattern using a developer. By the above processing, it is possible to obtain a resist pattern with a reduced hole inner diameter or separation width.

  As described above, according to the third embodiment, it is not necessary to generate an acid in the first resist by the exposure process, and before forming the second resist on the first resist, A surface treatment with an acidic liquid is performed, and the acid is diffused by heat treatment to crosslink.

  In the third embodiment, examples of the first resist 21 include a positive resist composed of a novolak resin and a naphthoquinonediazide-based photosensitizer used in the first embodiment. Further, as the first resist, It is possible to apply a chemically amplified resist using a mechanism that generates an acid upon exposure, and any resist material that uses a reaction system that generates an acid upon exposure is not particularly limited. The other resist materials and second resist materials described in the first embodiment can be applied to the third embodiment.

  Further, the fine separation resist pattern 22a thus formed is formed on various semiconductor substrates, and using this as a mask, fine separation spaces or fine holes are formed on the semiconductor substrate to manufacture a semiconductor device. This is the same as in the first and second embodiments described above.

Example 1.
As the first resist, an i-line resist composed of novolak resin and naphthoquinone diazide and using 2-heptanone as a solvent was used to form a resist pattern.
First, after dropping and spin-coating the resist on a Si wafer, pre-baking was performed at 80 ° C./70 seconds to evaporate the solvent in the resist to form a first resist with a film thickness of about 0.8 μm.
Next, the i-line reduced projection exposure apparatus was used as the exposure apparatus, and the first resist was exposed using the mask as shown in FIG. 1 as the exposure mask. Next, PEB treatment is performed at 115 ° C./90 seconds, followed by development using an alkaline developer (NMD3: manufactured by Tokyo Ohka Kogyo Co., Ltd.) to obtain a resist pattern having a separation size as shown in FIG. It was.

Example 2
A resist pattern was formed using an i-line resist composed of novolak resin and naphthoquinone diazide as the first resist and using ethyl lactate and propylene glycol monoethyl acetate as the solvent.
First, the resist was formed on the Si wafer so as to have a film thickness of about 1.0 μm by dropping and spin coating. Next, pre-baking was performed at 90 ° C./70 seconds to dry the solvent in the resist. Subsequently, exposure was performed using a Nikon stepper and a mask as shown in FIG.
Next, PEB treatment is performed at 115 ° C./90 seconds, followed by development using an alkaline developer (NMD3: manufactured by Tokyo Ohka Kogyo Co., Ltd.) to obtain each resist pattern having a separation size as shown in FIG. It was.

Example 3 FIG.
As the first resist, a chemically amplified excimer resist (manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used to form a resist pattern.
First, the resist was formed on the Si wafer so as to have a film thickness of about 0.85 μm by dropping and spin coating. Next, pre-baking was performed at 90 ° C./70 seconds to dry the solvent in the resist. Subsequently, exposure was performed using a mask as shown in FIG. 1 using a KrF excimer reduction projection exposure apparatus.
Next, PEB treatment is performed at 110 ° C./70 seconds, followed by development using an alkali developer (NMD-W: manufactured by Tokyo Ohka Kogyo Co., Ltd.), and each resist pattern having a separation size as shown in FIG. Got.

Example 4
A resist pattern was formed using a chemically amplified resist composed of t-Boc polyhydroxystyrene and an acid generator as the first resist.
First, the resist was formed on the Si wafer so as to have a film thickness of about 0.60 μm by dropping and spin coating. Next, baking was performed at 115 ° C./120 seconds to dry the solvent in the resist. Subsequently, (ESPACER ESP-100: manufactured by Showa Denko KK) was spin-coated on the resist as an antistatic film in the same manner, followed by baking at 90 ° C./90 seconds. Next, drawing is performed at 16.4 μC / cm ² using an EB drawing apparatus.
Next, after PEB was performed at 80 ° C./120 seconds, the antistatic film was peeled off using pure water, and then the resist pattern was developed using TMAH alkaline developer (NMD-W: manufactured by Tokyo Ohka Kogyo Co., Ltd.). It was.
As a result, each EB resist pattern of about 0.24 μm as shown in FIG. 10 was obtained.

  Next, examples relating to the second resist material will be described.

Reference Example 1
As a second resist material, a 1 L measuring flask was used, 380 g of ethylene glycol and 95 g of ethanol were added to 25 g of the polyvinyl acetal resin, and stirred and mixed at room temperature for 6 hours to obtain a 5 wt% solution of the polyvinyl acetal resin.

Reference Example 2
As a second resist material, a 1 L stopper bottle was used, 475 g of xylene was added to 25 g of polyvinylmethylsilsesquioxane, and mixed and dissolved overnight at room temperature using a wave rotary to obtain a 5 wt% solution of polyvinylmethylsilsesquioxane.

Reference Example 3
Using a 1 L volumetric flask as a second resist material, 100 g of methoxymethylene melamine and 900 g of methanol were stirred and mixed at room temperature for 6 hours to obtain an about 10 wt% methoxymethylene melamine solution.

Reference Example 4
As a second resist material, using a 1 L measuring flask, 100 g of (N-methoxymethyl) methoxyethyleneurea, 100 g of (N-methoxymethyl) hydroxyethyleneurea, and 100 g of N-methoxymethylurea were respectively 750 g of ethanol, 50 g of isopropanol was stirred and mixed at room temperature for 8 hours to obtain about 10 wt% ethylene urea solution.

Reference Example 5
As a second resist material, 160 g of the polyvinyl acetal solution obtained in Reference Example 1 , 20 g of the methoxymethylol melamine solution obtained in Reference Example 3 and 20 g of isopropanol are stirred and mixed at room temperature for 6 hours to obtain a mixed solution of a resin and a crosslinking agent. It was.

Reference Example 6
As the second resist material, 180 g of the polyvinyl acetal solution obtained in Reference Example 1 , 20 g of the (N-methoxymethyl) methoxyethyleneurea solution obtained in Reference Example 4 , 20 g of (N-methoxymethyl) hydroxyethyleneurea, N-methoxy In 20 g of methylurea, 20 g of methoxybenzene was mixed with stirring at room temperature for 8 hours to obtain a mixed solution of a resin and a crosslinking agent.

Reference Example 7
As the second resist material, 160 g of the polyvinylmethylsilsesquioxane solution obtained in Reference Example 2 , 10 g, 20 g, and 30 g of the methoxyethylene urea solution obtained in Reference Example 4 and 20 g of methoxybenzene were each 6 hours at room temperature. Mixed.
As a result, three types of second resist solutions having concentrations of about 11 wt%, 20 wt%, and 27 wt% of methoxyethylene urea as a crosslinking agent for the polyvinylmethylsilsesquioxane resin were obtained.

Example 5 .
As a second resist, 0 g, 35.3 g, and 72.2 g of 5 wt% methoxybenzene solution of polyvinylsiloxane resin were mixed with 100 g of the polyvinylmethylsilsesquioxane resin solution obtained in Reference Example 2 at room temperature. The mixture was stirred for 6 hours to obtain three types of mixed solutions having different mixing ratios of the polyvinylmethylsilsesquioxane resin and the polyvinylsiloxane resin.

Example 6 .
The second resist material obtained in Example 5 was dropped on the Si wafer on which the first resist pattern obtained in Example 2 was formed and spin-coated, followed by prebaking at 90 ° C./70 seconds, 2 resist films were formed. Next, mixing baking (MB) was performed at 115 ° C./90 seconds to advance the crosslinking reaction. Next, after developing using a mixed solvent of methoxybenzene and xylene, rinsing with xylene, developing and peeling off the non-crosslinked layer, and subsequent post-baking at 100 ° C./90 seconds, FIG. As shown, a second resist cross-linked layer was formed on the first resist pattern.
In this case, the resin was changed by changing the mixing ratio of the resin, and as clearly shown in Table 1 showing the change of the resist pattern size after the cross-linking formation, the mixing of the polyvinyl methyl silsesquioxane resin and the polyvinyl siloxane resin. By changing the amount, the thickness of the crosslinked layer formed on the first resist can be controlled.

  By forming a cross-linked layer using this silicone-based resin, the dry etching resistance was improved by about 40 times at the etching rate as compared to before the cross-linked layer was formed.

Reference Example 8
The resin obtained in Reference Example 1 was dropped as a second resist material onto the Si wafer on which the first resist pattern obtained in Example 1 was formed and spin-coated, and then pre-baked at 90 ° C./70 seconds. A second resist film was formed.
Next, the entire surface of the wafer was exposed using an i-line exposure apparatus. Furthermore, mixing baking (MB) was performed at 135 ° C./70 seconds to advance the crosslinking reaction. Next, development is performed using a mixed solution of ethylene glycol and ethanol, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 120 ° C./90 seconds, as shown in FIG. A second resist cross-linked layer was formed on the pattern. Thus, as clearly shown in Table 2, when the entire resist exposure pattern size of 0.35 μm before the formation of the cross-linked layer is exposed to about 0.38 μm, the entire exposure is not performed. In some cases, the size was reduced by about 0.26 μm.

  In this case, when the entire surface exposure was performed before MB baking, the cross-linking reaction proceeded more than in the case where it was not performed, and a thick cross-linked layer was formed on the first resist surface.

Example 7 .
On the Si wafer on which the first resist pattern obtained in Example 2 was formed, the mixed solution of the polyvinylmethylsilsesquioxane resin, polyvinylsiloxane resin and ethyleneurea obtained in Example 5 was used as the second resist. It was.
After the second resist material was dropped and spin-coated, prebaking was performed at 80 ° C./70 seconds to form a second resist film.
Next, mixing baking (MB) was performed under three conditions of 100 ° C./90 seconds, 110 ° C./90 seconds, and 120 ° C./90 seconds to perform a crosslinking reaction. Next, development is performed using a mixed solvent having a methoxybenzene / ethanol mixing ratio of 2/1, 1/1, 1/2, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 90 ° C./90 seconds. By performing, as shown in FIG. 11, the 2nd resist bridge | crosslinking layer was formed on the 1st resist pattern.
As a result, as clearly shown in Table 3, the inner diameter of the 0.4 μm size hole pattern formed in Example 2 and the size of the space in the line pattern and the isolated remaining pattern were reduced in the resist pattern after the formation of the crosslinked layer. The reduction amount increases as the MB temperature increases.

Furthermore, it was observed that the lower the mixing ratio of methoxybenzene in the developer, the slower the dissolution of the crosslinked layer, the smaller the pattern size, and the closer the taper angle of the pattern approaches 90 degrees.
From this, it can be seen that by controlling the MB temperature and the composition of the developer, it is possible to control the cross-linking reaction with high accuracy and further improve the pattern shape.

Reference Example 9
After the Si wafer on which the first resist pattern obtained in Example 3 was formed was cured at 110 ° C., the polyvinyl acetal solution obtained in Reference Example 1 and the polyvinyl acetal resin solution obtained in Reference Example 6 were formed on the wafer. And three kinds of mixed solutions having different concentrations of methoxyethylene urea as a crosslinking agent were used as the second resist.
After the second resist material was dropped and spin-coated, prebaking was performed at 85 ° C./70 seconds to form a second resist film.
Next, mixing baking (MB) was performed at 65 ° C./70 seconds + 100 ° C./90 seconds to perform a crosslinking reaction. Next, development is performed using a mixed solvent of methyl cellosolve and ethanol, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 90 ° C./90 seconds, as shown in FIG. A second resist cross-linked layer was formed on the pattern.
As a result, as clearly shown in Table 4, the inner diameter of the hole pattern having a size of about 0.28 μm formed in Example 3 is reduced as shown in Table 4, and the reduction amount is the amount of the crosslinking agent mixed. The larger it becomes, the larger it becomes.

  From this, it can be seen that the cross-linking reaction can be accurately controlled by adjusting the mixing ratio of the materials. Furthermore, since heat treatment is performed after forming the first resist pattern, methyl cellosolve, which is a good solvent for the first resist, can be used for the second resist. It can be seen that there is an effect of lowering the solubility in a solvent.

Reference Example 10
On the Si wafer on which the first resist pattern obtained in Example 3 was formed, the polyvinyl acetal solution obtained in Reference Example 2 , the polyvinyl acetal resin solution obtained in Reference Example 6 , and N-methoxymethyl- which is a crosslinking agent A mixed solution of methoxyethylene urea, (N-methoxymethyl) hydroxyethylene urea, and N-methoxymethyl urea was used as the second resist.
After the second resist material was dropped and spin-coated, prebaking was performed at 85 ° C./70 seconds to form a second resist film.
Next, mixing baking (MB) was performed at 70 ° C./70 seconds + 110 ° C./90 seconds to perform a crosslinking reaction. Next, development is performed using pure water, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 85 ° C./90 seconds, so that the second resist is formed on the first resist pattern as shown in FIG. A resist cross-linked layer was formed.
As a result, as clearly shown in Table 5, the inner diameter of the hole pattern having a size of about 0.28 μm formed in Example 3 was reduced, and the reduction amount was different depending on the difference in the crosslinking group of the crosslinking agent. It is done.

  From this, it can be seen that the cross-linking reaction can be controlled depending on the kind of the material to be mixed.

Reference Example 11
On the Si wafer on which the first resist pattern obtained in Example 3 was formed, the polyvinyl acetal solution obtained in Reference Example 1 , the polyvinyl acetal resin solution obtained in Reference Example 6 and a methoxyethylene urea mixed solution as a crosslinking agent Was used as the second resist.
After the second resist material was dropped and spin-coated, prebaking was performed at 80 ° C./70 seconds to form a second resist film.
Next, 90 seconds of mixing baking (MB) was performed at a predetermined temperature to perform a crosslinking reaction. Next, development is performed using a mixed solvent of ethylene glycol and isopropanol, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 90 ° C./90 seconds, as shown in FIG. A second resist cross-linked layer was formed on the pattern.
As a result, as clearly shown in Table 6, the resist pattern size of about 0.28 μm formed in Example 3 is reduced, and a difference is recognized depending on the amount of the crosslinking agent and the reaction temperature.

  From this, it can be seen that the present invention can control the resist pattern size by a crosslinking reaction even when a chemically amplified resist that generates an acid by light irradiation is used.

Reference Example 12
On the Si wafer on which the first resist pattern obtained in Example 4 was formed, the polyvinyl acetal aqueous solution obtained in Reference Example 1 , the polyvinyl acetal resin solution obtained in Reference Example 6 and a methoxyethylene urea mixed solution as a crosslinking agent Was used as the second resist.
After the second resist material was dropped and spin-coated, prebaking was performed at 80 ° C./70 seconds to form a second resist film.
Next, mixing baking (MB) was performed at 105 and 115 ° C./90 seconds to perform a crosslinking reaction. Next, development is performed using a mixed solvent of ethylene glycol, isopropanol, and pure water, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 90 ° C./90 seconds, as shown in FIG. A second resist cross-linked layer was formed on one resist pattern.
As a result, as clearly shown in Table 7, the size of the resist pattern having a size of about 0.24 μm formed in Example 4 was reduced, and a difference in the reduction amount was recognized depending on the difference in the crosslinking agent.

  Therefore, the present invention can control the resist pattern size by a crosslinking reaction even when a chemically amplified EB resist composed of t-Boc-polyhydroxystyrene and an acid generator is used.

Reference Example 13
The first resist pattern obtained in Example 2 was selectively irradiated with an electron beam (irradiation amount: 80 μC / cm ² ).
Next, the polyvinyl acetal resin solution obtained in Reference Example 6 and a methoxyethylene urea mixed aqueous solution as a crosslinking agent were applied as a second resist onto a resist pattern irradiated with an electron beam. Application is performed by dropping and spin-coating the second resist material, followed by pre-baking at 85 ° C./70 seconds to form a second resist film, and then mixing baking (MB) at 115 ° C./90 seconds. ) To carry out a crosslinking reaction.
Finally, development is performed using a mixed solution of ethylene glycol and isopropanol, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 105 ° C./70 seconds, as shown in FIG. A second resist cross-linking layer was selectively formed on the pattern.
As a result, as clearly shown in Table 8, the resist pattern of about 0.4 μm formed in Example 2 was reduced in the portion that was not irradiated with the electron beam, and the portion that was selectively irradiated with the electron beam. As for No, no cross-linking reaction occurred and no reduction in hole size was observed.

  Therefore, in the present invention, after the resist pattern is formed, the electron beam is selectively irradiated so that no reaction occurs in the irradiated pattern, so that the resist pattern can be selectively controlled in size. I understand that.

Reference Example 14 .
A weak hydrochloric acid aqueous solution was spin-coated on the Si wafer on which the first resist pattern obtained in Example 2 was formed, and dried at 100 ° C./70 seconds. Thereafter, polyvinyl methyl silsesquioxane containing 11% of methoxyethylene urea obtained in Reference Example 7 was dropped and spin coated as a second resist material, and then pre-baked at 90 ° C./70 seconds to obtain a second resist film. Formed. Next, mixing baking (MB) was performed at 120 ° C./90 seconds to advance the crosslinking reaction. Next, after developing using a mixed solvent of methoxybenzene and xylene, rinsing with xylene, developing and peeling off the non-crosslinked layer, and subsequent post-baking at 110 ° C./90 seconds, FIG. As shown, a second resist cross-linked layer was formed on the first resist pattern.

  As is apparent from Table 9, it can be seen that the pattern size can be reduced by treating the first resist pattern with an acidic solution.

Reference Example 15 .
On the Si wafer on which the first resist pattern obtained in Example 3 was formed, a plastic solution was added to a mixed solution of the polyvinyl acetal resin solution obtained in Reference Example 6 and (N-methoxymethyl) hydroxyethylene urea as a crosslinking agent. As the second resist, 5 wt% of phthalate ester as an agent or 1 wt% of a block copolymer type nonionic surfactant of ethylene oxide and propylene oxide as a surfactant was used.
After the second resist material was dropped and spin-coated, prebaking was performed at 85 ° C./70 seconds to form a second resist film. By adding the surfactant, the coating unevenness was eliminated and the coating uniformity was remarkably improved.
Next, mixing baking (MB) was performed at 100 ° C./90 seconds to perform a crosslinking reaction. Next, development is performed using a mixed solvent of ethylene glycol, pure water, and isopropanol, the non-crosslinked layer is developed and peeled off, and then post-baked at 90 ° C./90 seconds, as shown in FIG. A second resist cross-linked layer was formed on one resist pattern.

  As a result, as is clear from Table 10, it can be seen that the inner diameter of the hole pattern having a size of about 0.28 μm formed in Example 3 can be controlled by the presence or absence of a plasticizer or a surfactant additive. Moreover, the effect of shortening the development time and improving the hole shape was also recognized by adding the additive.

Reference Example 16 .
A resin composition in which the degree of acetalization of the polyvinyl acetal resin of the resin obtained in Reference Example 5 is different from 10%, 30%, and 60% on the Si wafer on which the first resist pattern obtained in Example 1 is formed. After dropping and spin coating as a second resist material, pre-baking was performed at 90 ° C./70 seconds to form a second resist film.
Furthermore, mixing baking (MB) was performed at 115 ° C./70 seconds to advance the crosslinking reaction. Next, development is performed using a mixed solution of ethylene glycol and methanol, and the non-crosslinked layer is developed and peeled off, followed by post-baking at 110 ° C./90 seconds, as shown in FIG. A second resist cross-linked layer was formed on the pattern.

  As is clear from Table 11, as the degree of acetalization of the polyvinyl acetal resin increased, the crosslinking reaction further progressed, and a thicker crosslinked layer was formed on the first resist surface.

Reference Example 17
The first resist pattern obtained in Example 3 was formed on the Si wafer on which the oxide film was formed, and the first resist pattern as shown in FIG. 13 was formed.
Next, the second resist material obtained in Reference Example 7 was dropped and spin-coated, followed by prebaking at 80 ° C./70 seconds, followed by mixing baking (MB) at 110 ° C./70 seconds to perform a crosslinking reaction. Made progress. Next, development was performed using xylene, the non-crosslinked layer was developed and peeled off, and subsequently post-baked at 105 ° C./90 seconds to form a second resist crosslinked layer on the first resist hole pattern. . Furthermore, the underlying oxide film was etched using an etching apparatus, and the pattern shape after etching was observed.
Further, as a comparative example, a wafer formed with the first resist pattern shown in FIG. 13 that was not subjected to the treatment of the present invention was also etched in the same manner. As a result, as clearly shown in Table 12, when the present invention was applied, an oxide film pattern with a reduced separation width was obtained.

As described above, according to the present invention, a resist material for forming a finely separated resist pattern that enables the formation of a pattern exceeding the wavelength limit in making the resist separation pattern and hole pattern finer is obtained.
As a result, the hole diameter of the hole resist pattern can be reduced as compared with the conventional one, and the separation width of the space resist pattern can be reduced as compared with the conventional one.
Further, by using the finely divided resist pattern thus formed as a mask, finely separated spaces or holes can be formed on the semiconductor substrate.
In addition, a semiconductor device having a finely separated space or hole can be obtained.

It is a mask pattern figure used for embodiment of this invention. It is a process flow diagram for demonstrating the resist pattern formation method of Embodiment 1 using the resist material of this invention. It is a process flow diagram for demonstrating the resist pattern formation method of Embodiment 1 using the resist material of this invention. It is a process flow diagram for demonstrating the resist pattern formation method of Embodiment 1 using the resist material of this invention. It is a process flowchart for demonstrating the resist pattern formation method of Embodiment 2 using the resist material of this invention. It is a process flow diagram for demonstrating the resist pattern formation method of Embodiment 3 using the resist material of this invention. It is a top view which shows the 1st resist pattern in Example 1 of this invention. It is a top view which shows the 1st resist pattern in Example 2 of this invention. It is a top view which shows the 1st resist pattern in Example 3 of this invention. It is a top view which shows the 1st resist pattern in Example 4 of this invention. It is a top view which shows the 2nd resist pattern in the Example of this invention, and a reference example . It is a top view which shows the 2nd resist pattern in the Example of this invention, and a reference example . It is a top view which shows the 2nd resist pattern in the reference example of this invention.

  DESCRIPTION OF SYMBOLS 1, 11 and 21 1st resist, 1a, 11a and 21a 1st resist pattern, 2, 12 and 22 2nd resist 3 Semiconductor substrate 4, 14, and 24 Crosslinked layer.

Claims (3)

Provided on the first resist pattern on the substrate, does not dissolve the first resist pattern, causes a crosslinking reaction with an acid to form a crosslinked layer at the interface portion in contact with the first resist pattern, and non-crosslinked A resist material that is developed with a developer that develops a portion,
Unsaturated polyester, polymethyl methacrylate, polyimide, urethane resin, phenol resin, cellulose resin, maleic acid resin, epoxy resin, and polyvinylmethylsilsesquioxane resin and polyvinylsiloxane Resin mixed resin , guanidine, thiazole, thiuram, dithioicarbamate organic accelerator, isocyanate, polyfunctional epoxy, polyfunctional acrylic resin, polyfunctional urethane, polyfunctional silicone resin A resist material comprising at least one of a monomer and an oligomer .   Dibutyl phthalate, dioctyl phthalate, butyl benzyl phthalate, tributyl phosphate, triphosfort, tricresyl phosphate, butyl ricinoleate, dibutyl succinate, methyl acetyl riceal, butyl phthalyl butyl glycolate, triethylene glycol, diethyl butyrate , Polyethylene glycol, ethylene glycol, glycerin, propylene glycol, 3-methylenepentane-1,3,5-triol, triethylene glycol dibutyrate, dibutyl sebacate, dioctyl sebacate, epoxidized soybean oil, castor oil, chlorinated paraffin The resist material according to claim 1, comprising at least one of them. Lecithin derivative, propylene glycol fatty acid ester, glycerin fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyglycerin fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbit fatty acid ester, polyoxyethylene alkyl ether, polyoxy Ethylene alkylphenol, polyoxyethylene alkylphenyl formaldehyde condensate, polyoxyethylene castor oil, hydrogenated castor oil, polyoxyethylene sterol, hydrogenated sterol, polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether , Polyoxyethylene alkyl phenyl ether, poly Oxyethylene lanolin or lanolin alcohol, beeswax derivative, polyoxyethylene alkylamine or fatty acid amide, polyoxyethylene alkyl ether phosphate, phosphate, alkyl ether carboxylate, alkyl phosphate and polyoxyethylene alkyl ether phosphate , Alkylbenzenesulfonate, sulfonate, quaternary ammonium salt, alkylpyridinium salt, betaine acetate type amphoteric surfactant, imidazoline type amphoteric surfactant, block polymerization type nonionic surfactant of ethylene oxide and propylene oxide Agent, perfluoroalkyl sulfonate, perfluoroalkyl carboxylate, perfluoroalkyl polyoxyethylene ethanol, perfluoroalkyl quaternary ammonium iodide, fluorinated al Resist material according to claim 1, characterized in that it comprises at least one of glycol ester.

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