JP2001147538A - Positive type resist laminated body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive type resist laminated body adaptable to exposure in the far ultraviolet region and having high resolving power in the production of a semiconductor device and to provide a positive type resist laminated body giving a resist pattern nearly free from line waving particularly in a minute line/space of <=0.2 μm, less liable to produce residue on development and having high suitability to production. SOLUTION: Each of the positive type resist laminated bodies has a 1st resist layer on a substrate and a 2nd resist layer on the 1st resist layer. The 1st resist layer is a layer which contains a polymer containing specified repeating units and is cured under heat. The 2nd resist layer contains (b) a polysiloxane or a polysilsesquioxane having an acid decomposable group and having solubility in an alkali developing solution increased by the action of an acid and (c) a compound which generates the acid when irradiated with active light or radiation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive resist laminate for exposure to radiation such as ultraviolet rays, far ultraviolet rays, X-rays, electron beams, molecular beams, gamma rays, and synchrotron radiation. In the process of manufacturing semiconductors such as ICs, it relates to a positive resist laminate for microfabrication which provides a resist having a particularly high resolution and sensitivity, a rectangular cross-sectional shape, and has a wide process tolerance, which is used, for example, when manufacturing a circuit board or the like. . The positive resist laminate of the present invention can be used in the following steps. For example, semiconductor wafers,
Alternatively, an antireflection layer or an organic film is provided on or on a substrate made of glass, ceramics, metal, or the like, and is applied to a thickness of 0.01 to 3 μm by spin coating or roller coating. Thereafter, the film is heated and dried, and a circuit pattern or the like is baked through an exposure mask by irradiation with actinic rays or the like, and developed to obtain a positive image. Further, the substrate can be processed in a pattern by etching using the positive image as a mask. Typical application fields include a semiconductor manufacturing process such as an IC, a circuit board manufacturing such as a liquid crystal and a thermal head, and other photofabrication processes.

[0002]

2. Description of the Related Art The resolution limit of conventional single-layer resists has become evident with the increasing integration of LSIs. By forming resists in multiple layers instead of single layers, thick and fine high-profile ratio patterns can be formed. Methods of forming have been proposed.
That is, a thick organic polymer film is formed on the first layer, a thin resist material layer is formed on the second layer thereon, and then the second resist material is irradiated with high energy rays and developed. The organic polymer of the first layer is subjected to oxygen plasma etching (O ₂ -RI
E) Anisotropic etching is performed to obtain a pattern having a high rectangular shape (Rin, Solid State Technology, Vol. 24, p. 73 (198)
1)).

In this case, the second resist layer is made of O ₂ -R
Silicon-containing polymers are commonly used because of their high IE resistance. In particular, many attempts have been made to use an acid-decomposable group-containing polysiloxane or polysilsesquioxane having a silicon atom in the polymer main chain in order to increase the silicon content. For example, JP-A-63-
No. 218948, JP-A-4-245248, 6-1.
Nos. 84311, 8-160620 and JP-A-9-27
No. 4319 and the like. The first resist layer is made of a novolak resin or the like in order to impart adhesion and film forming properties to the substrate, high dry etching resistance, immiscibility with the second resist layer, high light absorption characteristics at the exposure wavelength, and the like. Is generally and widely used.

However, this method has poor adhesion to a second resist layer using polysiloxane or polysilsesquioxane, and is therefore particularly disadvantageous when used for forming fine lines / spaces of 0.2 μm or less. However, there is a problem that the line is easily undulated and the pattern is likely to collapse. Further, in the first resist layer containing the novolak resin, it is necessary to perform a high-temperature treatment for a long time, and there is a problem that the suitability for production is extremely low in the production of semiconductor devices and the like. If the high-temperature treatment is performed in a short time, the solidification of the first resist layer becomes insufficient, and a phenomenon (intermix) of mixing with the second resist layer occurs. As a result, there is also a problem that a pattern with a large development residue is formed. .

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a positive resist laminate having a high resolving power and capable of coping with exposure in the far ultraviolet region in the manufacture of semiconductor devices. Another object of the present invention is to provide a positive resist laminate which provides a resist pattern with less line waviness particularly in a fine line / space of 0.2 μm or less. Another object of the present invention is to provide, among other things, 0.1.
An object of the present invention is to provide a positive resist laminate having a small amount of development residue in a fine line / space of 2 μm or less. Another object of the present invention is to provide a positive resist laminate having high manufacturing suitability.

[0006]

Means for Solving the Problems The inventors of the present invention have made intensive studies while paying attention to the above characteristics, and as a result, have completed the present invention. That is, the object of the present invention can be achieved by the following configurations. 1. A positive resist laminate having a first resist layer on a substrate and a second resist layer on this layer, comprising: [I]
The first resist layer is a layer containing (a-1) a polymer containing a repeating unit represented by the following general formula (1) and being cured by heat; [II] the second resist layer is composed of (b) A) polysiloxane or polysilsesquioxane having a group decomposable by an acid and having a property of increasing the solubility in an alkaline developer by the action of an acid, and (c) an acid upon irradiation with actinic rays or radiation. A positive-working resist laminate comprising:

[0007]

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In the formula, R1 represents a hydrogen atom, an alkyl group, or a halogen atom, L1 and L2 each independently represent a divalent linking group, M represents an aromatic group, a, b, c Is
Each independently represents 0 or 1. 2. The positive resist laminate according to the above (1), wherein the polymer (a-1) contained in the first resist layer further contains a repeating unit represented by the following general formula (2).

[0009]

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In the formula, R2 has the same meaning as R1 in the general formula (1). L3 represents a divalent linking group. 3. The first resist layer is activated by the acid (a-2) and reacts with the polymer containing the repeating unit represented by the general formulas (1) and (2) to form a crosslinked structure. 1. A cross-linking agent, and (a-3) a compound which generates an acid by heat. 4. The positive resist laminate according to item 1. 4. Polysiloxane or polysilsesquioxane having a group decomposable by the acid of the component (b) contained in the second resist layer and having a property of increasing the solubility in an alkaline developer by the action of an acid is used. Wherein the side chain has a structure represented by the following general formula (3). 4. The positive resist laminate according to item 1.

[0011]

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In the formula, J1 represents an alkylene group which may have a substituent, and J2 represents an arylene group which may have a substituent or a cycloalkylene group which may have a substituent. , J3 represents a divalent linking group, and J4 represents 2 to
G represents a tetravalent linking group, and G represents a group decomposed by the action of an acid. k, l, m, and n each independently represent 0 or 1. However, k, l, m, and n are not 0 at the same time. p represents an integer of 1 to 3. 5. The above-mentioned 1. A step of providing a first resist layer according to claim 1; a step of heat-treating and curing the first resist layer; a step of providing the second resist layer according to claim 1 on the first resist layer; The layer, the step of exposing actinic rays or radiation to a desired pattern, the step of developing the exposed second resist layer with an alkaline developer, and the second resist layer formed in the pattern as a mask, 1. A method for forming a fine pattern, comprising a step of etching one resist layer.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below, but the present invention is not limited to these embodiments. The positive resist laminate of the present invention comprises a first resist layer containing a polymer having a repeating unit represented by the general formula (1) as a component (a-1), and a group decomposable by an acid as a component (b). And a polysiloxane or polysilsesquioxane having a property of increasing the solubility in an alkaline developer by the action of an acid, and (c) a compound containing a compound capable of generating an acid by irradiation with actinic rays or radiation. And two resist layers.

In order to further improve the effect of the present invention, the content of the repeating unit represented by the general formula (1) in the polymer (a-1) contained in the first resist layer is as follows: It is preferably 20 to 99% by weight, more preferably 30 to 98% by weight, and particularly preferably 40 to 95% by weight based on the total weight of the polymer.
In the general formula (1), R1 is a hydrogen atom, an alkyl group (preferably an alkyl group having 1 to 6 carbon atoms) or a halogen atom (Cl, Br, I, etc.), preferably a hydrogen atom, 1 to 3 carbon atoms. And particularly preferably a hydrogen atom, a methyl group or an ethyl group. L1 represents a divalent linking group, and is preferably an alkylene group, an arylene group, or an aralkylene group. These groups may have a substituent. Examples of the substituent include Cl, Br,
Halogen atom such as F, -CN group, -OH group, amino group,
C1-C4 alkyl group, C3-C8 cycloalkyl group, C1-C4 alkoxy group, C6-C12
And an aralkyl group having 7 to 14 carbon atoms. More preferably, L1 is an alkylene group having 1 to 8 carbon atoms which may have a substituent, a phenylene group which may have a substituent, and 7 to 7 carbon atoms which may have a substituent. An aralkylene group of 10 and an alkylene group having 2 to 6 carbon atoms which may have a substituent and a phenylene group which may have a substituent are particularly preferable.

L2 represents a divalent linking group, and specifically,
-COO-, -OCO-, -O-, -CON (R11)
-, -N (R11) CO-, -N (R11)-, -NH
It preferably represents -CO-NH-, -OCOO-.
Here, R11 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. Preferred L2 is -COO-,-
OCO-, -O-, -N (R11) CO-, -N (R1
1)-. a, b and c each independently represent 0 or 1. M represents an aromatic group and may have a substituent. Examples of the substituent include those described above as the substituent such as the alkylene group for L1. Preferred M includes a phenyl group, a substituted phenyl group, a naphthyl group, a substituted naphthyl group, a biphenyl group, a substituted biphenyl group, an anthryl group, a substituted anthryl group, a phenanthryl group, a substituted phenanthryl group, and more preferably a phenyl group, A substituted phenyl group, a naphthyl group, a substituted naphthyl group, a biphenyl group, and a substituted biphenyl group.

The (a-1) polymer contained in the first resist layer is used in order to further improve the effect of the present invention.
It is preferable to further include a repeating unit represented by the general formula (2). In the general formula (2), R2 has the same meaning as R1, L3 represents a divalent linking group, and preferably
Is synonymous with As L3, a more preferred linking group is an alkylene group having 1 to 8 carbon atoms which may have a substituent,
A phenylene group which may have a substituent, an aralkylene group having 7 to 10 carbon atoms which may have a substituent,
An alkylene group having 2 to 6 carbon atoms which may have a substituent and a phenylene group which may have a substituent are particularly preferred. In the polymer (a-1) contained in the first resist layer, the content of the repeating unit represented by the general formula (2) is preferably 1 to 80% by weight based on the total weight of the polymer, and 2 It is more preferably from 70 to 70% by weight, particularly preferably from 5 to 60% by weight.

The polymer (a-1) used in the present invention improves the film-forming properties, adhesion, developability, etc., in addition to the repeating units represented by the above general formulas (1) and (2). It may further contain other repeating units for the purpose.

Monomers corresponding to such other repeating units include, for example, acrylates, methacrylates, acrylamides, methacrylamides,
Examples include compounds having one addition-polymerizable unsaturated bond selected from allyl compounds, vinyl ethers, vinyl esters, and the like. Specifically, for example, acrylates such as alkyl (the alkyl group has 1 to 1 carbon atoms)
10 are preferred) acrylates (eg, methyl acrylate, ethyl acrylate, propyl acrylate,
Amyl acrylate, cyclohexyl acrylate, ethylhexyl acrylate, octyl acrylate, t-octyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate, 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimethylol Propane monoacrylate,
Pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, etc.);

Methacrylic esters such as alkyl (alkyl having preferably 1 to 10 carbon atoms) methacrylate (for example, methyl methacrylate,
Ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate,
Benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate,
5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, etc.);

Acrylamides, for example, acrylamide, N-alkylacrylamide, (where the alkyl group has 1 to 10 carbon atoms, for example, methyl, ethyl, propyl, butyl, t-butyl, heptyl, octyl) Group, cyclohexyl group, hydroxyethyl group, etc.), N, N-dialkylacrylamide (alkyl group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, butyl group, isobutyl group, ethylhexyl group, Cyclohexyl group, etc.), N-hydroxyethyl-N-methylacrylamide, N-2-
Acetamidoethyl-N-acetylacrylamide and the like;

Methacrylamides, for example, methacrylamide, N-alkyl methacrylamide (alkyl having 1 to 10 carbon atoms, for example, methyl, ethyl, t-butyl, ethylhexyl, hydroxyethyl, cycloethyl) Groups, etc.), N, N-dialkyl methacrylamide (alkyl groups include ethyl group, propyl group, butyl group, etc.), N-hydroxyethyl-N-methyl methacrylamide and the like;

Allyl compounds such as allyl esters (eg, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, etc.), allyloxy Ethanol, etc .;

Vinyl ethers such as alkyl vinyl ethers (eg, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2-ethyl Butyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether, etc.);

Vinyl esters, such as vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxy acetate, vinyl butoxy acetate , Vinyl acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinylcyclohexylcarboxylate, etc.);

Dialkyl itaconates (eg, dimethyl itaconate, diethyl itaconate, dibutyl itaconate, etc.); dialkyl esters of fumaric acid (eg, dibutyl fumarate, etc.) or monoalkyl esters; acrylic acid, methacrylic acid, crotonic acid , Itaconic acid, maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, maleilenitrile and the like. In addition, any addition-polymerizable unsaturated compound copolymerizable with the above various repeating units may be used.

The weight average molecular weight of the polymer (a-1) used in the present invention is not particularly limited, but the component (a-2)
In view of the compatibility with the thermal crosslinking agent of (a-3), the thermal acid generator of (a-3), organic solvent properties, film forming properties, and the like, it is preferably 1,000 to 1,000,000, and more preferably 2,000 to 100,000. Specific examples of the polymer (a-1) used in the present invention include the following, but are not limited thereto. The numbers in parentheses are mole fractions.

[0027]

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[0028]

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[0029]

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In the present invention, the content of the polymer (a-1) in the first resist layer is preferably 30 to 98% by weight, more preferably 50% by weight, based on the total solid content of the first resist layer. ~ 95% by weight. The first resist layer is
In order to further improve the effects of the present invention together with the polymer (a-1), the polymer is activated by an acid (a-2) and represented by the general formulas (1) and (2). A thermal crosslinking agent capable of forming a crosslinked structure by reacting with a polymer containing a repeating unit (also referred to as a “thermal crosslinking agent”); and (a-3) a compound that generates an acid by heat (“thermal acid generation”). Agent). As the thermal cross-linking agent, known compounds can be widely used, and examples thereof include, for example, a melamine compound, a benzoguanamine compound, and a glycol substituted with at least one group selected from a methylol group, an alkoxymethyl group, and an acyloxymethyl group. A uryl compound or a urea compound is preferably exemplified. Examples of the alkoxymethyl group include methoxymethyl, ethoxymethyl, propoxymethyl, butoxymethyl and the like. As an acyloxymethyl group,
Acetyloxymethyl and the like can be mentioned. The number of methylol groups, alkoxymethyl groups, and acyloxymethyl groups contained in these compounds is 2 to 6, preferably 5 to 6, in the case of a melamine compound per molecule, and the number of glycoluril compounds and benzoguanamine compounds per molecule. In case 2
4, preferably 3 to 4. In the case of a urea compound, the number is 3 to 4. Among these, hexamethoxymethylmelamine, tetramethoxymethylbenzoguanamine, and tetramethoxymethylglycoluril compounds are most preferable from the viewpoints of thermal crosslinkability and storage stability.

All of the above methylol group-containing compounds can be obtained by reacting melamine, guanamine or urea with formalin in the presence of a basic catalyst such as sodium hydroxide, potassium hydroxide, ammonia and tetraalkylammonium hydroxide. The alkoxymethyl group-containing compound can be obtained by heating the methylol group-containing compound in an alcohol in the presence of an acid catalyst such as hydrochloric acid, sulfuric acid, nitric acid, and methanesulfonic acid. The acyloxymethyl group-containing compound is obtained by reacting the methylol group-containing compound with an acid anhydride or an acid halide in the presence of a base catalyst. The content of the thermal crosslinking agent in the composition of the first resist layer in the present invention is usually 2 to 50% by weight, preferably 5 to 30% by weight in terms of solid content.

(A-3) As the thermal acid generator, those having a temperature at which an acid starts to be generated at a temperature of 150 to 220 ° C. are preferable.
Those having a temperature of 70 to 200 ° C are more preferable. Further, it is preferable to use a sulfonic acid ester compound or a diaryliodonium salt. The sulfonic acid ester compound is preferably an organic sulfonic acid ester having 3 to 20 carbon atoms, specifically, a sulfonic acid ester of a secondary alcohol such as 2-propanol, 2-butanol, 2-pentanol or cyclohexanol. Is preferred. Examples of the diaryliodonium salt compound include a diaryliodonium cation and an anion of an organic sulfonic acid, SbF ₆
Salts with anions, PF ₆ anions or AsF ₆ anions are mentioned. Here, the anion of an organic sulfonic acid is preferable as the anion. Specific examples of the diaryliodonium salt compound include the following compounds.

[0033]

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[0034]

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[0035]

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[0036]

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Among these, salts of diaryliodonium and organic sulfonic acid are preferred from the viewpoints of stability and solvent solubility. Among them, the aryl group has 1 to 12 carbon atoms.
A linear or branched alkyl group having 1 to 1 carbon atoms
A salt of a diaryliodonium cation having an alkoxy group of 2 as a substituent and an organic sulfonic acid anion is also preferable from the viewpoint of safety. Here, as a linear or branched alkyl group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms, methyl, ethyl, n-propyl, i-propyl, n-butyl Group, sec-butyl group, i-butyl group, t-butyl group, n-amyl group, i
-Amyl group, t-amyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-
A decyl group, an n-dodecyl group, a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a methoxy group, an ethoxy group, a propoxy group, and a butoxy group are exemplified. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group.

Examples of the organic sulfonic acid anion include trifluoromethanesulfonate, methanesulfonate, a linear or branched alkyl group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms on an aryl group. Examples of the alkyl group and the alkoxy group are the same as those described above.) Or an arylsulfonate which may have a halogen atom as a substituent is preferable from the viewpoint of solvent solubility. Examples of the aryl group include the same as those described above. These thermal acid generators can be used alone or in combination of two or more. The thermal acid generator is usually used in the composition 10 of the first resist layer.
It is blended in a proportion of usually 0.5 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 0 parts by weight in terms of solid content.

The composition of the first resist layer of the positive resist laminate of the present invention contains the polymer (a-1) described above,
(A-2) In addition to the thermal crosslinking agent and (a-3) the thermal acid generator,
In order to improve film forming property, heat resistance, dry etching resistance and the like, other polymers may be further added. Preferred examples of such polymers include novolak phenol resins, specifically phenol aldehyde resins, o-
A cresol formaldehyde resin, a p-cresol formaldehyde resin, a xylenol formaldehyde resin, a co-condensate thereof, or the like is used. Further, as described in JP-A-50-125806,
A condensate of phenol or cresol substituted with an alkyl group having 3 to 8 carbon atoms, such as t-butylphenol aldehyde resin, and a condensate of formaldehyde may be used together with the phenol resin described above. Also, N-
A polymer having a phenolic hydroxy group-containing monomer such as (4-hydroxyphenyl) methacrylamide as a copolymer component, or a homopolymer such as p-hydroxystyrene, o-hydroxystyrene, m-isopropenylphenol, or p-isopropenylphenol; Alternatively, a copolymerized polymer, or a polymer in which these polymers are partially etherified or partially esterified can also be used.

The composition for forming the first resist layer may include, if necessary, an aromatic polycyclic compound described in JP-A-4-122938, JP-A-2-27555, JP-A-4-230754, and the like. A hydroxy compound may be added. Further, the composition for forming the first resist layer includes:
It may contain an organic basic compound. Examples of the organic basic compound include the same compounds as those to be blended in the composition of the second resist layer described later. Among them, guanidine, 1,1-dimethylguanidine, 1,1,3,
3-tetramethylguanidine, 2-aminopyridine, 3
-Aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4
-Methylpyridine, 2-amino-5-methylpyridine,
2-amino-6-methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4- Amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-
Aminoethyl) pyrrolidine, pyrazole, 3-amino-
5-methylpyrazole, 5-amino-3-methyl-1-
p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine,
-Pyrazoline, 3-pyrazolin, N-aminomorpholine, N- (2-aminoethyl) morpholin, imidazole, benzimidazole, phenylimidazole, diphenylimidazole, triphenylimidazole and the like are preferred.

Component (a-1) in the first resist layer,
Examples of the solvent for dissolving (a-2) and (a-3) include ketones such as methyl ethyl ketone and cyclohexanone, alcohol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, dioxane, and ethylene glycol dimethyl ether. Ethers, cellosolve esters such as methyl cellosolve acetate and ethyl cellosolve acetate, fatty acid esters such as butyl acetate, methyl lactate and ethyl lactate, halogenated hydrocarbons such as 1,1,2-trichloroethylene, dimethylacetamide, N- Highly polar solvents such as methylpyrrolidone, dimethylformamide, and dimethylsulfoxide can be exemplified. These solvents can be used alone or as a mixture of a plurality of solvents.

The composition of the first resist layer may optionally contain a dye, a plasticizer, an adhesion aid, a surfactant and the like. Specific examples include methyl violet,
Dyes such as crystal violet and malachite green, stearic acid, acetal resin, phenoxy resin,
Plasticizers such as alkyd resins and epoxy resins; adhesion aids such as hexamethyldisilazane and chloromethylsilane; and surfactants such as nonylphenoxypoly (ethyleneoxy) ethanol and octylphenoxypoly (ethyleneoxy) ethanol. Surfactants that can be used include those described in detail below. As the dye, a dye containing an alkali-soluble group such as an aromatic hydroxyl group or a carboxylic acid group in the molecule, such as curcumin, is particularly preferably used.

Next, (b) used for the second resist layer
The polysiloxane or polysilsesquioxane having a group decomposable by an acid and having a property of increasing the solubility in an alkaline developer by the action of an acid will be described.
As the polysiloxane or polysilsesquioxane of the component (b), those having a group capable of decomposing by the action of an acid on the side chain are mentioned, and preferably have a structure represented by the following general formula (3) in the side chain. Things. Thereby, the resist performance such as the resolution and the heat resistance are excellent.

[0044]

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In the formula, J1 represents an alkylene group which may have a substituent, preferably an alkylene group having 1 to 10 carbon atoms which may have a substituent. The same substituents as those described above as examples of the substituent such as the alkylene group of L1 in the general formula (1) can be used.
Desirable J1 is an alkylene group having 1 to 6 carbon atoms,
More preferably, it is an alkylene group having 1 to 4 carbon atoms (methylene group, ethylene group, propylene group, etc.). k represents 0 or 1. J2 is an arylene group which may have a substituent, and preferably has 6 to 1 carbon atoms which may have a substituent.
4 represents an arylene group or a cycloalkylene group which may have a substituent, preferably a cycloalkylene group having 4 to 10 carbon atoms which may have a substituent. Examples of these substituents include J1 It is the same as the description of Preferred J
2 is an arylene group having 6 to 10 carbon atoms (phenylene group,
A cycloalkylene group having 5 to 8 carbon atoms (such as a cyclohexylene group and a cyclooctylene group). l represents 0 or 1.

J3 represents a divalent linking group. As the linking group, -O-, -N (R21)-, -COO-, -OC
(= O)-, -O (C = O) O-, -CON (R21)
—, —N (R21) CO— and —NH—CO—NH— groups. R21 has the same meaning as R11 in formula (1). Preferred J3 is -COO-,-
OCO-, -O-, -CON (R21)-, -N (R2
1) CO-. m represents 0 or 1. J4 is 2-4
Represents a valent linking group. Examples of the linking group include an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 10 carbon atoms, a bicycloalkylene group having 5 to 10 carbon atoms, and a 5 to 10 carbon atoms.
And an arylene group having 6 to 12 carbon atoms, and a trivalent or tetravalent group formed by removing one or two hydrogen atoms from these groups. More preferable linking groups include an alkylene group having 1 to 5 carbon atoms, a trivalent group formed by removing one hydrogen atom from the alkylene group, a bicycloalkylene group having 5 to 8 carbon atoms,
Examples thereof include a tricycloalkylene group having 5 to 8 carbon atoms, a phenylene group, and a trivalent or tetravalent group formed by removing one or two hydrogen atoms from a phenylene group. n represents 0 or 1.

G represents a group decomposed by the action of an acid, that is, an acid-decomposable group. Preferred acid-decomposable groups include -COO
-R31, -OCO-R31, -O- CH (CH 3) -
_{O-R32, -COOCH (CH 3} ) -O-R32 can be mentioned. Here, R31 represents a tertiary alkyl group, preferably a tertiary alkyl group having 4 to 8 carbon atoms (t-butyl group,
t-amyl group). R32 represents an alkyl group having 2 to 12 carbon atoms which may have a substituent or an aralkyl group having 7 to 14 carbon atoms which may have a substituent. Examples of the substituent include the same as those described above as examples of the substituent such as the alkylene group of L1 in the general formula (1). Preferred examples of R32 include an ethyl group, a propyl group, a butyl group, an isobutyl group, a t-butyl group, an isoamyl group, a cyclohexylmethyl group, a cyclohexylethyl group, a benzyl group, a phenethyl group, and a phenyloxyethyl group. p represents an integer of 1 to 3.
k, l, m, and n are never 0 at the same time.

In the general formula (3), the polysiloxane or polysilsesquioxane of the component (b) is not an acid-decomposable group in the general formula (3) but from the viewpoint of improving solubility and improving lithography performance. It is preferred to have a side chain that is a group and / or a -COOH group. In this case, G is -OH
The proportion of the side chain that is a group and / or a —COOH group is preferably 0 to 60% by mole fraction of the total amount of G and the side chain when G is an acid-decomposable group. More preferably, it is 40%.

For the purpose of improving lithography performance, film forming property and heat resistance, the component (b) polysiloxane or polysilsesquioxane is represented by the following general formulas (4) and / or (5). It is preferable to have a side chain.

[0050]

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In the formula, J5 has the same meaning as J1 and J6 has the same meaning as J2. q and r each independently represent 0 or 1. A is
Represents an alkyl group, an aryl group, or an aralkyl group, each of which may have a substituent. Examples of the substituent include those exemplified as the substituent such as the alkylene group of L1 in the general formula (1). A preferably has 1 carbon atom
An alkyl group having 10 to 10, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, more preferably
An alkyl group having 1 to 8 carbon atoms (methyl group, ethyl group, propyl group, cyclohexylmethyl group, etc.), an aryl group having 6 to 9 carbon atoms (phenyl group, p-methylphenyl group, etc.),
An aralkyl group having 7 to 10 carbon atoms (such as a benzyl group or a phenethyl group) is exemplified. L7 is synonymous with J1. R4
1, and R42 are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Further, R41 and R42 may combine with each other to form a ring. In this case, the number of rings is 1-3
It is preferable that the number is the same, and the one having the following structure is also preferable.

[0052]

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The proportion of the repeating unit having a side chain represented by the general formulas (4) and / or (5) is 0 in terms of mole fraction among all the repeating units present in the polymer of the component (b). It is preferably from 70% to 70%, more preferably from 0 to 60%, particularly preferably from 0 to 50%.

The weight-average molecular weight of the acid-decomposable group-containing polysiloxane and polysilsesquioxane of the component (b) contained in the second resist layer of the present invention is not particularly limited. In view of the balance of solubility, organic solvent solubility, performance, and the like, it is preferably 1,000 to 100,000,
500-50,000 is preferred. Hereinafter, specific examples of the polysiloxane and the polysilsesquioxane of the component (b) contained in the second resist layer of the present invention will be described, but the present invention is not limited thereto. In the following specific examples, the term "protection ratio" refers to the ratio of protection in the case of protecting a group exhibiting solubility in an alkaline developer with an acid-decomposable group, expressed as mol%.

[0055]

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[0056]

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[0057]

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[0058]

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[0059]

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[0060]

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In the present invention, the amount of the component (b) added to the second resist layer is preferably from 50 to 99% by weight, more preferably from 70 to 99% by weight, based on the total weight of the solid content of the second resist layer. 98% by weight. The component (c) blended in the composition for forming the second resist layer of the positive resist laminate of the present invention is a compound which decomposes upon irradiation with actinic rays or radiation to generate an acid, ie, a photoacid. It is a generator. As the photoacid generator, a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or an acid by a known light used in a micro resist or the like. Generated compounds and their mixtures can be appropriately selected and used.

For example, SI Schlesinger, Photogr. Sc
i. Eng., 18, 387 (1974), TS Bal etal, Pol ymer,
21, 423 (1980) etc., U.S. Pat.
No. 4,069,055, 4,069,056, Re 27,992, JP-A-3
Ammonium salts described in -140140, etc., DC Necker et.
al, Macromolecules, 17, 2468 (1984), CS Wen eta
l, Teh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo,
Oct (1988), U.S. Pat.Nos. 4,069,055 and 4,069,056, phosphonium salts described in JV Crivello et al, Macro
morecules, 10 (6)., 1307 (1977), Chem. & Eng. News,
Nov. 28, p31 (1988), European Patent No. 104,143, U.S. Patent Nos. 339,049, 410,201, JP-A-2-150,848, JP-A-2-296,514 and the like, iodonium salts described in JV Cri
vello etal, Polymer J. 17, 73 (1985), JV Crivello
etal. J. Org.Chem., 43, 3055 (1978), WR Watt
etal, J. Polymer Sci., Polymer Chem. Ed., 22, 1789
(1984), JV Crivello etal, Polymer Bull., 14, 27
9 (1985), JV Crivello et.al, Macromorecules, 14
(5), 1141 (1981), JV Crivello etal, J. Polymer S
ci., Polymer Chem.Ed., 17, 2877 (1979), European Patent Nos. 370,693, 161,811, 410,201, 339,049
Nos. 233,567, 297,443, 297,442, U.S. Pat.Nos. 4,933,377, 3,902,114, 4,760,013,
4,734,444, 2,833,827, German Patent 2,904,626
Nos. 3,604,580, 3,604,581, etc.
Salt, JV Crivello etal, Macromorecules, 10
(6), 1307 (1977), JV Crivello etal, J. Polymer S
ci., Polymer Chem. Ed., 17, 1047 (1979), etc., selenonium salts, CS Wen etal, Teh, Proc. Conf. R
ad. Curing ASIA, p478 Tokyo, Oct (1988), etc., onium salts such as arsonium salts, U.S. Pat.
No., JP-B-46-4605, JP-A-48-36281, JP-A-55-32
No. 070, JP-A-60-239736, JP-A-61-169835, JP-A-61-169837, JP-A-62-58241, JP-A-62-212401
No., JP-A-63-70243, organic halogen compounds described in JP-A-63-298339, K. Meier et al., J. Rad.
13 (4), 26 (1986), TPGill et al., Inorg. Chem., 1
9, 3007 (1980), D. Astruc, Acc. Chem. Res., 19 (12),
377 (1896), organometallics / organic halides described in JP-A-2-14145, S. Hayase et al., J. Polymer Sci., 2
5, 753 (1987), E. Reichmanis etal, J. Pholymer Sc
i., Polymer Chem. Ed., 23, 1 (1985), QQ Zhu eta
l, J. Photochem., 36, 85, 39, 317 (1987), B. Amit et.
al, Tetrahedron Lett., (24) 2205 (1973), DHR B
arton etal, J. Chem Soc., 357 1 (1965), PM Colli
ns et al, J. Chem. Soc., Perkin I, 1695 (1975), M.R.
udinstein etal, Tetrahedron Lett., (17), 1445 (197
5), JW Walker etal J. Am. Chem. Soc., 110, 7170
(1988), SC Busman et al., J. Imaging Technol., 11
(4), 191 (1985), HM Houlihan et al, Macor molecul
es, 21, 2001 (1988), PM Collins et al., J. Chem. So
c., Chem. Commun., 532 (1972), S. Hayase et al., Ma.
cromole cules, 18, 1799 (1985), E. Reichman is eta
l, J. Electrochem. Soc., Solid State Sci. Techno
l., 130 (6), FM Houlihan etal, Macromolcules, 2
1, 2001 (1988), European Patent Nos. 0290,750 and 046,083
No. 156,535, No. 271,851, No. 0,388,343, U.S. Pat.Nos. 3,901,710, 4,181,531, JP-A-60-198538
, A photoacid generator having an O-nitrobenzyl-type protecting group described in JP-A-53-133022, etc., M. TUNOOKAetal, Polyme
r Preprints Japan, 35 (8), G. Berner et al., J. Rad.
Curing, 13 (4), WJ Mijs etal, Coating Technol.,
55 (697), 45 (1983), Akzo, H. Adachi et al, Polymer Pr
eprints, Japan, 37 (3), European Patent Nos. 0199,672 and 845
No. 15, No. 044,115, No. 618,564, No. 0101,122, U.S. Pat.Nos. 4,371,605, 4,431,774, JP-A-64-18143
No. JP-A-2-245756, compounds that generate sulfonic acid upon photodecomposition represented by iminosulfonate and the like described in JP-A-3-140109, etc., described in JP-A-61-166544 and the like Disulfone compounds and the like can be mentioned.

Further, a group that generates an acid by these lights,
Alternatively, a compound having a compound introduced into the main chain or side chain of a polymer, for example, ME Woodhouse et al., J. Am. Chem.
Soc., 104, 5586 (1982), SP Pappas etal, J. Imag
ing Sci., 30 (5), 218 (1986), S. Kondo etal, Makromo
l. Chem., Rapid Commun., 9,625 (1988), Y. Yamadaet
al, Makromol.Chem., 152, 153, 163 (1972), JV Cr
ivello etal, J. Polymer Sci., Polymer Chem. Ed., 1
7, 3845 (1979), U.S. Patent 3,849,137, German Patent 39
14407, JP-A-63-26653, JP-A-55-164824, JP-A-Showa
Compounds described in JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029 and the like can be used. VNR Pillai, Syn
thesis, (1), 1 (1980), A. Abad etal, Tetra hedron Le
tt., (47) 4555 (1971), DHR Barton et al., J. Chem.
Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, and EP 126,712, etc., can also be used to generate a compound which generates an acid by light.

Among these, diazodisulfone compounds, substituted or unsubstituted salts of diaryliodonium or triarylsulfonium, and the like, from the viewpoints of acid generation efficiency by exposure, appropriate diffusion of acid, stability in resist, and the like.
In particular, a substituted or unsubstituted aryl sulfonate, camphor sulfonate and the like are preferable. In the present invention, the addition amount of the component (c) in the second resist layer
It is preferably 0.01 to 20% by weight, more preferably 0.1 to 10% by weight, based on the total weight of the solid content of the resist layer.

The solvent for dissolving the components (b) and (c) contained in the composition for forming the second resist layer and the various components described below to prepare the composition as a solution includes: The above-mentioned solvent used for dissolving the composition of the first resist can be used.

An organic basic compound can be blended with the composition for forming the second resist layer of the positive resist laminate of the present invention. This is preferable because the storage stability is improved and the line width change due to PED is reduced. Preferred organic basic compounds that can be used in the present invention are compounds that are more basic than phenol. Among them, a nitrogen-containing basic compound is preferable. Preferred chemical environments include the structures of the following formulas (A) to (E).

[0067]

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Here, R²⁵⁰, R²⁵¹And R²⁵²Are each
Independently, a hydrogen atom, an alkyl group having 1 to 6 carbon atoms,
1-6 aminoalkyl groups, hydroxy having 1-6 carbon atoms
Alkyl group or substituted or unsubstituted 6 to 20 carbon atoms
An aryl group, where R ²⁵¹And R²⁵²Are connected to each other
To form a ring.

[0069]

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In the above formula (E), R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ are the same or different and represent an alkyl group having 1 to 6 carbon atoms.

Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms having different chemical environments in one molecule, and particularly preferred is a ring structure containing a substituted or unsubstituted amino group and a nitrogen atom. Or a compound having an alkylamino group. Preferred specific examples are substituted or unsubstituted guanidine,
Substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazole, substituted or unsubstituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted Pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine, Substituted or unsubstituted imidazole, diazabicyclo compounds and the like can be mentioned. Preferred substituents are
Amino group, aminoalkyl group, alkylamino group, aminoaryl group, arylamino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxyl group, cyano group.

Particularly preferred compounds are guanidine,
1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine , 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-
6-methylpyridine, 3-aminoethylpyridine, 4-
Aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2
-Aminoethyl) piperidine, 4-amino-2,2,
6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1 -P-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N-
Examples include (2-aminoethyl) morpholin, imidazole, benzimidazole, phenylimidazole, diphenylimidazole, triphenylimidazole, and the like, but are not limited thereto.

These nitrogen-containing basic compounds are used alone or in combination of two or more. These nitrogen-containing basic compounds can be added to the composition of the first resist layer. The amount of the nitrogen-containing basic compound used is
Usually, 0.001 to 10 parts by weight per 100 parts by weight of the composition (excluding solvent) of the first resist layer or the second resist layer.
Parts by weight, preferably 0.01 to 5 parts by weight. 0.0
If the amount is less than 01 parts by weight, the above effects cannot be obtained. On the other hand, 10
If the amount exceeds the weight part, the sensitivity tends to decrease and the developability of the unexposed part tends to deteriorate.

The composition of each resist layer of the positive resist laminate of the present invention may further contain, if necessary, a surfactant,
Dyes, pigments, plasticizers, photosensitizers, and compounds having two or more phenolic OH groups that promote solubility in a developer can be contained.

Suitable surfactants include, specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether,
Polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene alkyl allyl ethers such as polyoxyethylene octyl phenol ether and polyoxyethylene nonyl phenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate ,
Sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan fatty acid esters such as sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; F-Top EF301, EF303;
EF352 (manufactured by Shin-Akita Chemical Co., Ltd.), MegaFac F1
71, F173 (manufactured by Dainippon Ink Co., Ltd.), Florado FC430, FC431 (manufactured by Sumitomo 3M Limited),
Asahi Guard AG710, Surflon S-382, SC
101, SC102, SC103, SC104, SC1
05, SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid or methacrylic acid (co) polymerized polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like.

These surfactants may be added alone or in some combination. The preferable addition amount is the first resist layer or the second resist layer.
0.0005 to 0.01 parts by weight based on 100 parts by weight of the composition of the resist layer (excluding the solvent).

Examples of the developing solution for the second resist layer include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, and monoamines such as ethylamine and n-propylamine. Amines, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxy An aqueous solution of an alkali such as a quaternary ammonium salt such as chloride or a cyclic amine such as pyrrole or piperidine can be used. Further, an appropriate amount of an alcohol, a surfactant, an aromatic hydroxyl group-containing compound, or the like can be added to the aqueous solution of the above-mentioned alkalis. Among them, it is particularly preferable to use tetramethylammonium hydroxide.

In the positive resist laminate of the present invention, a first resist layer is formed on a substrate. This layer is formed by dissolving the components contained in the first resist layer in a suitable solvent,
It is performed by applying the obtained solution by a spin coating method, a spray method, or the like. The thickness of the first resist layer is
It is preferably from 0.1 to 2.0 μm, more preferably from 0.2 to 1.5 μm, particularly preferably from 0.2 to 1.5 μm.
5 to 1.2 μm. When the thickness is less than 0.1 μm, it is not preferable from the viewpoint of antireflection and dry etching resistance, and when the thickness is more than 2.0 μm, the aspect ratio becomes too high,
There is a problem that the formed fine pattern easily collapses,
After all it is not desirable. Next, before forming a second resist layer, it is preferable to heat-treat the first resist layer before that. The temperature of the heat treatment is preferably from 150 to 250 ° C, more preferably from 170 to 240 ° C,
0-230 ° C is particularly preferred. When the temperature is lower than 150 ° C., when the second resist layer is applied, intermixing with the first resist layer is likely to occur, and when the temperature is higher than 250 ° C., the polymer in the first resist layer is likely to decompose and deteriorate. Not preferred. The time of the heat treatment varies depending on the heat treatment temperature.
In the case of the heat treatment at ° C., it is preferably set in the range of 10 seconds to 1000 seconds, more preferably 20 to 600 seconds.

Next, a second resist layer is formed on the first resist layer, which can be performed in the same manner as the formation of the first resist layer. The thickness of the second resist layer is set to 0.1.
It is preferably from 0.3 to 0.6 μm, more preferably from 0.04 to 0.5 μm, particularly preferably from 0.04 to 0.5 μm.
5 to 0.45 μm. The obtained second resist layer is
Next, a pattern forming step is performed. As a first step, a pattern forming process is first performed on the second layer of the resist composition film. The mask is adjusted as required, and high-energy rays are irradiated through the mask, so that the resist composition in the irradiated portion is made soluble in an aqueous alkaline solution, and developed with an aqueous alkaline solution to form a pattern.

Next, dry etching is performed as a second step. This operation is performed by oxygen plasma etching using the pattern of the resist composition film as a mask to form a fine pattern having a high aspect ratio.
The etching of the organic polymer film contained in the first resist layer by the oxygen plasma etching is completely different from the plasma etching used when the resist film is peeled off after the etching of the substrate is completed by a conventional photoetching operation. It is the same technology. This operation is performed by, for example, a reactive gas,
That is, it can be performed using oxygen as an etching gas.

[0081]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but, of course, the present invention is not limited to these examples.

<Synthesis of (a-1) polymer and (b) polymer> Synthesis Example 1 (Synthesis of (a-1) polymer: P-5, used in Examples 2, 3, 6, 9 to 11) After dissolving 18.6 g of -hydroxybiphenyl and 10.5 g of methacrylic acid chloride in 50 ml of ethyl acetate, 10.1 g of triethylamine was added dropwise. After reacting at 40 ° C. for 2 hours, 1 liter of distilled water was added and collected by decantation. The product was purified by silica gel column chromatography. The yield was 75%. (Synthesis of polymer) After dissolving 22.4 g of the above monomer and 3.2 g of 2-hydroxyethyl methacrylate in 100 g of DMF, the reaction solution was heated to 65 ° C, and at the same time, nitrogen was passed through the reaction solution for 30 minutes. 50 mg of V-65 (a product of Wako Pure Chemical Industries, Ltd.) was added three times every two hours as a polymerization initiator. The reaction product was recovered as a powder by reprecipitation in 1 liter of distilled water. GPC analysis of the obtained polymer showed that the weight average molecular weight was 8,200 in terms of standard polystyrene.

Synthesis Example 2 ((a-1) Polymer: P-16
Synthesis, used in Examples 4, 5, and 13) 14.2 g of glycidyl methacrylate, 21.8 g of 3-hydroxy-7-methoxy-2-naphthoic acid, and 0.5 g of methoxyhydroquinone were added to 60 ml of acetone. 10.1 g of triethylamine was added dropwise. 70
After the reaction at 4 ° C. for 4 hours, 0.5 liter of distilled water was added and collected by decantation. The product was purified by silica gel column chromatography. The yield is 80
%Met. (Synthesis of Polymer) After dissolving 20.2 g of the above monomer and 1.6 g of 2-hydroxyethyl methacrylate in 60 g of DMF, the reaction solution was heated to 65 ° C., and simultaneously, nitrogen was passed through the reaction solution for 30 minutes. As a polymerization initiator, 35 mg of V-65 (a product of Wako Pure Chemical Industries, Ltd.) was added three times every two hours. The reaction product was recovered as a powder by reprecipitation in 1 liter of distilled water. GPC analysis of the obtained polymer showed that the weight average molecular weight was 9,100 in terms of standard polystyrene.

Synthesis Example 3 ((b) Polymer: Synthesis of C-5, used in Example 14) 20 g of 3-chloropropyltrimethoxysilane was added to 200 ml of dried N, N-dimethylacetamide, and then diphenol acid was added. 28.7 g, potassium iodide 3.0
g and DBU 16.0 g were added. The reaction was carried out at 70 to 90 ° C. for 5 hours in a dry nitrogen atmosphere. The reaction solution was returned to room temperature and used as it was in the next step. (Synthesis of Unprotected Polymer) To the above reaction solution, 20 g of phenyltrimethoxysilane and 14.5 g of distilled water were added, and 50
The reaction was carried out at a temperature of 120 ° C for 3 hours and then at 120 ° C for 12 hours. After neutralizing the reaction solution with dilute hydrochloric acid, it was poured into 3 liters of distilled water with stirring to obtain 51 g of white solid powder. (Synthesis of C-5) After the above white powder was dried under vacuum, 20 g of the white powder was dissolved in 100 ml of THF. Then, 2.0 g of ethyl vinyl ether and p-toluenesulfonic acid-
20 mg of hydrate was added and reacted at room temperature for 10 hours. After quenching the reaction by adding triethylamine, the mixture was poured into 2 L of distilled water with stirring to precipitate a polymer, which was then dried at room temperature under reduced pressure to obtain 16.2 of the target polymer, C-5.
g was obtained.

Example 1 (1) Formation of First Resist Layer Component (a-1): Compound Example P-5 (synthesized in Synthesis Example 1) (Weight average molecular weight = 7500) 4.5 g Component (a-2) : 0.375 g of hexamethylolmelamine Component (a-3): 0.125 g of di (t-amyl) phenyliodonium-2,4,6-triisopropylsulfonate is dissolved in 28 g of methoxypropyl acetate, and the obtained solution is dissolved in 0 g of methoxypropyl acetate. The solution was finely filtered through a 1 μm-diameter membrane filter to obtain a first resist composition. This composition was applied to a silicon wafer using a coater CDS-650 manufactured by Canon, and heated at 90 ° C. for 90 seconds to form a film having a thickness of 0.65 μm.
Was obtained. This was further heated at 200 ° C. for 90 seconds to obtain a first resist layer having a thickness of 0.50 μm. (2) Formation of Second Resist Layer Component (b): Compound Example C-4 (weight average molecular weight = 5800) 0.9 g Component (c): triphenylsulfonium-2,4,6-triisopropylsulfonate 05 g triphenylimidazole 0.006 g was dissolved in methoxypropyl acetate 9 g, and the resulting solution was subjected to microfiltration with a 0.1 μm-diameter membrane filter to obtain a second resist composition. On the first resist layer, a second resist layer is similarly applied,
By heating at 90 ° C. for 90 seconds, a second resist layer having a thickness of 0.20 μm was obtained.

The wafer obtained in this manner was manufactured by Canon Kr.
An F excimer laser stepper FPA3000EX5 was loaded with a resolving power mask and exposed while changing the exposure amount. Thereafter, the film was heated at 90 ° C. for 90 seconds in a clean room, developed with a tetrahydroammonium hydroxide developer (2.38%) for 60 seconds, rinsed with distilled water and dried to obtain a pattern (upper layer pattern). The pattern was observed with a scanning electron microscope. Further, the wafer having the pattern of the upper layer was etched (dry developed) using a parallel plate type reactive ion etching apparatus manufactured by ULVAC to form a pattern on the lower layer. Etching gas is oxygen, pressure is 20 mTorr, applied power is 100 mW / c.
m ² , and the etching time was 15 minutes. The formed resist pattern was observed with a scanning electron microscope.

The following methods were used to evaluate the resolving power, line pattern undulation, and development residue. (1) Resolving power: At the minimum exposure amount at which a 0.18 μm line / space of the mask was reproduced, evaluation was made with a minimum dimension at which the line / space was separated and resolved in the upper layer (second resist layer). (2) Line pattern undulation: upper layer (second resist layer)
In the pattern, the deviation of the line from the straight line in the length direction of 20 μm in the length direction of the 0.18 μm line of the mask was evaluated by an average value measured at arbitrary 20 points. (3) Development residue: Visual evaluation of the degree of occurrence (electron microscope)
The evaluation was made on a five-point scale of 5 (significantly small), 4 (small), 3 (somewhat seen), 2 (many), and 1 (significantly). As a result, the resolving power was 0.15 μm, the waviness of the line pattern was 0.006 μm, and the development residue was as good as Level 1.

Examples 2 to 20 The components (a-1) and (a-
2), (a-3), (b), and (c) are replaced with the components (a-1), (a-2), (a-3),
Using (b) and (c) in the same amounts as in Example 1, and further using other components as necessary, exposure and development and etching treatments were performed in the same manner as in Example 1, and observed with a scanning electron microscope. The evaluation was performed in the same manner as in Example 1. Table 3 shows the results.

Comparative Examples 1 to 3 The components (a-1) and (a-
FH, a general-purpose i-line resist containing a novolak resin and a quinonediazide-based photosensitizer instead of 2) and (a-3)
Using i-028DD (resist for i-line manufactured by Fuji Film Ohlin Co., Ltd.), the high-temperature heating conditions were 200 ° C./90
Second (Comparative Example 1), 200 ° C./10 minutes (Comparative Example 2), 20
Except that the temperature was set to 0 ° C./60 minutes (Comparative Example 3), exposure, development, and etching were performed in the same manner as in Example 1, and the resultant was observed with a scanning electron microscope and evaluated in the same manner as in Example 1. Table 3 shows the results.

[0090]

[Table 1]

[0091]

[Table 2]

[0092]

[Table 3]

From the evaluation results of Examples 1 to 16 and Comparative Examples 1 to 3 shown in Table 3, the following is clear.
That is, from the resist laminate of the example, a resist pattern is solidified by a high-temperature treatment for a short time of 90 seconds, and a resist pattern with high resolution and little line waviness and development residue can be formed. On the other hand, in the case of the comparative example in which the conventional i-line resist is used for the first resist layer, the resolving power is low, the line waviness is large, and the amount of development residue is large in the same short-time high-temperature treatment as in the example. The long-term high-temperature treatment reduces the resolution, line waviness, and development residue, but is inferior to the performance of the examples, and the long-term treatment greatly reduces the suitability for production.

[0094]

The positive resist laminate of the present invention can cope with exposure in the far ultraviolet region and has a high resolution. Also,
A resist pattern with less line waviness and development residue in a fine pattern of 0.2 μm or less can be formed. Further, high-temperature treatment can be performed in a short time, and the suitability for production is excellent. Therefore, the composition of the present invention is very suitably used for mass production of semiconductor substrates having ultrafine circuits.

Claims (5)

[Claims] 1. A positive resist laminate having a first resist layer on a substrate and a second resist layer on this layer, wherein [I] the first resist layer comprises (a-1) A polymer containing a repeating unit represented by 1),
And (II) a second resist layer which has a group which can be decomposed by an acid and whose solubility in an alkali developing solution is increased by the action of an acid. A positive resist laminate comprising: siloxane or polysilsesquioxane; and (c) a compound that generates an acid upon irradiation with actinic rays or radiation. Embedded image In the formula, R 1 represents a hydrogen atom, an alkyl group, or a halogen atom, L 1 and L 2 each independently represent a divalent linking group, M represents an aromatic group, and a, b, and c each represent Independently
Represents 0 or 1. 2. (a-1) contained in a first resist layer
The positive resist laminate according to claim 1, wherein the polymer further contains a repeating unit represented by the following general formula (2). Embedded image In the formula, R2 has the same meaning as R1 in formula (1). L
3 represents a divalent linking group. 3. The first resist layer is activated by an acid (a-2) and reacts with a polymer containing a repeating unit represented by the general formulas (1) and (2) to form a crosslinked structure. 3. A heat-crosslinking agent which can be used as a binder, and (a-3) a compound which generates an acid by heat.
4. The positive resist laminate according to item 1. 4. A polysiloxane or a polysiloxane having a group decomposable by an acid of the component (b) contained in the second resist layer and having a property of increasing the solubility in an alkaline developer by the action of an acid. The positive resist laminate according to claim 1, wherein the sesquioxane has a structure in a side chain represented by the following general formula (3). Embedded image In the formula, J1 represents an alkylene group which may have a substituent, J2 represents an arylene group which may have a substituent or a cycloalkylene group which may have a substituent, and J3 represents J4 represents a divalent linking group, J2 represents a divalent to tetravalent linking group, and G represents a group decomposed by the action of an acid. k,
l, m and n each independently represent 0 or 1. However,
k, l, m, and n are never 0 at the same time. p is 1
Represents an integer of 1 to 3. 5. A step of providing the first resist layer according to claim 1 on a substrate, a step of heat-treating and curing the first resist layer, and a step of curing the first resist layer according to claim 1 on the first resist layer. (2) a step of providing a resist layer, a step of exposing the second resist layer to actinic rays or radiation in a desired pattern, a step of developing the exposed second resist layer with an alkaline developer, and forming the pattern in the pattern A step of etching the first resist layer using the formed second resist layer as a mask.