JP2001092154A - Method for forming pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming patterns by which the formation of an organic silicon mask retaining a masking property to a film to be processed without being deteriorated is made possible. SOLUTION: This method includes a stage for forming resist patterns on a substrate to be processed, a stage for embedding an organic silicon compound having the bond of silicon and silicon in the main chain into the apertures of the resist patterns, a stage for heating the resist patterns above a temperature at which the dissolution suppressing group or dissolution suppressing agent in the resist decomposes and a stage for forming the organic silicon film patterns by immersing the resist patterns into a solution which dissolves the resist and removing the resist patterns.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pattern forming method, and more particularly to a pattern forming method using an organic silicon film as a mask in the manufacture of a semiconductor device.

[0002]

2. Description of the Related Art In a method of manufacturing a semiconductor device, there are many processing steps of an insulating film. Usually, in these processing steps, a photosensitive resin film called a resist film is formed on an insulating film, pattern exposure is performed on the photosensitive resin film, a resist pattern is formed through a developing step, and the resist pattern is further etched with an etching mask. Is used to dry-etch the insulating film.

However, it is necessary to reduce the thickness of the resist film in order to provide the necessary resolution, exposure latitude, or focus latitude during pattern exposure. The required film thickness cannot be secured.

In order to solve this problem, there is a method of forming a mask material on an insulating film which is more resistant to etching than a resist film, and sequentially transferring the pattern from the resist pattern to the mask material and then to the film to be processed. Have been.

[0005] As a mask material used in this method, an organic silicon film such as polysilane has conventionally been used.

[0006]

However, when an organic silicon film is used as a mask material, radicals penetrating from a side wall of the organic silicon film when patterning the organic silicon film by RIE using a resist as a mask. There has been a problem that the organic silicon film is deteriorated and the masking property for the film to be processed is deteriorated.

[0007]

SUMMARY OF THE INVENTION The present invention has been made under the above circumstances, and provides a pattern forming method capable of forming an organic silicon mask without deteriorating the maskability of a film to be processed. The purpose is to:

[0008]

In order to solve the above-mentioned problems, the present invention embeds a film having resistance to processing of a substrate to be processed between resist patterns formed on the substrate to be processed, A pattern forming method for forming a mask pattern on a substrate to be processed by removing a resist pattern is provided.

In the pattern forming method, there are the following three inventions corresponding to the resist pattern removing method.

A first aspect of the present invention is a method of forming a resist pattern on a substrate to be processed, a step of embedding an organic silicon compound having a silicon-silicon bond in a main chain in an opening of the resist pattern, Heating the pattern to a temperature above the temperature at which the dissolution inhibiting group or dissolution inhibitor in the resist decomposes, and immersing the resist pattern in a solution for dissolving the resist, removing the resist pattern, and removing the organic silicon film pattern Forming a pattern.

A second invention provides a process for forming a resist pattern on a substrate to be processed, a process for embedding an organic silicon compound having a silicon-silicon bond in a main chain in an opening of the resist pattern, A step of irradiating the pattern with radiation, heating, or a combination thereof; and a step of immersing the resist pattern in a solution for dissolving a resist, removing the resist pattern, and forming an organic silicon film pattern. A method for forming a pattern is provided.

A third aspect of the present invention is a method for forming a resist pattern on a substrate to be processed, a step of embedding an organic silicon compound having a silicon-silicon bond in a main chain in an opening of the resist pattern, A) a solution containing at least one kind of solvent contained in the resist, (b) a surfactant, and (c) at least one kind selected from the group consisting of an alkaline aqueous solution having a concentration higher than 0.20 N; Dipping the resist pattern to remove the resist pattern to form an organic silicon film pattern.

As described above, the pattern forming method of the present invention is characterized in that an organic silicon compound is buried in an opening of a resist pattern, and then the resist pattern is removed by various methods to form an organic silicon film pattern. And

To form an organic silicon film pattern in the opening of the resist pattern, a coating type mask material such as polysilane is applied to the front surface of the substrate on which the resist pattern has been formed by spin coating, and then this is etched back. This is performed by leaving the organic silicon film pattern in the opening of the resist pattern.

According to the pattern forming method of the present invention configured as described above, it is possible to efficiently remove only the resist pattern without deteriorating the organic silicon film. It is possible to obtain a mask pattern made of a silicon compound.

Next, the first to third components configured as described above will be described.
The pattern forming method according to the present invention will be described in more detail.

In the pattern forming method according to the first to third aspects, first, a resist pattern is formed on a substrate to be processed. As the substrate to be processed, a silicon oxide film on the surface,
A substrate on which a silicon nitride film, a silicon oxynitride film, spin-on-glass, or the like is formed can be given.

In order to form a resist pattern on a substrate to be processed, first, a resist solution is applied to the substrate to be processed, and a heating process is performed to form a resist film. The thickness of the resist film is preferably in the range of 100 to 500 nm.

The type of the resist is not particularly limited, and a positive type or a negative type can be selected and used according to the purpose. Specifically, as the positive resist, for example, a resist (IX-770, manufactured by Nippon Synthetic Rubber Co., Ltd.) composed of naphthoquinonediazide and a novolak resin, a polyvinylphenol resin protected with t-BOC and an acid generator Chemically amplified resist (APEX-
E, manufactured by Shipley Co., Ltd.). Examples of the negative resist include, for example, a chemically amplified resist (SNR200, manufactured by Shipley Co., Ltd.) comprising polyvinylphenol, a melamine resin and a photoacid generator, and a resist (RD) comprising polyvinylphenol and a bisazide compound.
-2000N, manufactured by Hitachi Chemical Co., Ltd.), but is not limited thereto.

In selecting a resist, it is necessary to select a resist according to a method of removing a resist pattern described later. For example, generally, a cross-linked negative resist is difficult to dissolve in an alkali developer after pattern formation. Therefore, when a method of removing a resist pattern using an alkali developing solution is employed, the use of a cross-linked negative resist is not appropriate.

These resist solutions are placed on a substrate to be processed.
For example, after applying by a spin coating method, a dip method, or the like, a resist film is formed by heating to evaporate the solvent.

Next, the resist film surface is exposed to a predetermined pattern. The exposure light source is not limited, and examples thereof include ultraviolet light, X-rays, electron beams, and ion beams. As the ultraviolet light, a mercury lamp g-line (43
6 nm), i-line (365 nm), or XeF (wavelength = 3
51 nm), XeCl (wavelength = 308 nm), KrF
(Wavelength = 248 nm), KrCl (wavelength = 222 n)
m), ArF (wavelength = 193 nm), F ₂ (wavelength = 15
Excimer laser such as 1 nm).

Then, for the exposed resist film, T
A resist pattern is formed by performing development processing with an alkaline developer such as MAH or choline.

If necessary, an antireflection film may be interposed between the substrate to be processed and the resist film in order to prevent the exposure light from being reflected from the substrate to be processed when light exposure is performed. preferable.

Next, an organic silicon film having a bond of silicon and silicon in a main chain is formed on the entire surface by a coating method.
Hereinafter, a method of forming an organic silicon film by a coating method will be described.

First, an organic silicon compound is dissolved in an organic solvent to prepare a solution material. Examples of the organosilicon compound having a silicon-silicon bond in its main chain include polysilane represented by the general formula (SiR ₁₁ R ₁₂ ) (where R ₁₁ and R ₁₂ are hydrogen atoms or carbon atoms). 1-20 substituted or unsubstituted aliphatic hydrocarbons or aromatic hydrocarbons, etc.).

The polysilane may be a homopolymer or a copolymer, and may have a structure in which two or more kinds of polysilanes are bonded to each other via an oxygen atom, a nitrogen atom, an aliphatic group or an aromatic group. Specific examples of the organic silicon compound are shown in the following formulas [1-1] to [1-114]. In the formula, m,
n represents a positive integer.

The weight average molecular weight of these compounds is not particularly limited, but is preferably from 200 to 100,000. The reason is that if the molecular weight is less than 200, the organic silicon film is dissolved in the resist solvent, while
If it exceeds 000, it is difficult to dissolve in an organic solvent and it is difficult to prepare a solution material.

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The organic silicon compound is not limited to one kind, and several kinds of compounds may be mixed. In addition, if necessary, a thermal polymerization inhibitor for measuring storage stability, an adhesion improver for improving adhesion to a silicon-based insulating film, a conductive substance, a substance which becomes conductive by light or heat. ,
Alternatively, a crosslinking agent capable of crosslinking an organic silicon compound may be added.

Examples of the conductive substance include organic sulfonic acids, organic carboxylic acids, polyhydric alcohols, polyhydric thiols (eg, iodine and bromine), SbF ₅ , PF ₅ , B
F ₅ , SnF _{5 and the} like.

Examples of the substance that becomes conductive by energy such as light or heat include carbon clusters (C60, C70), cyanoanthracene, dicyanoanthracene, triphenylpyrium, tetrafluoroborate, tetracyanoquinodimethane, and tetracyanoethylene. Phthalimide triflate, perchloropentacyclododecane, dicyanobenzene, benzonitrile, trichloromethyltriazine, benzoyl peroxide, benzophenonetetracarboxylic acid, t-butyl peroxide and the like.

More specifically, the following formulas [2-1] to [2]
-106].

[0048]

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Examples of the cross-linking agent include an organic silicon compound having a multiple bond and an acrylic unsaturated compound.

The solvent may be a polar organic solvent or a non-polar organic solvent. Specifically, ethyl lactate (E
L), ethyl-3-ethoxypropionate (EE
P), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), etc., ketones such as cyclohexane, 2-heptanone, 3-heptanone, acetylacetone, cyclopentanone, propylene glycol monoethyl ether acetate, ethyl Ester such as cellosolve acetate, methyl cellosolve acetate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, methyl-3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, diethylene glycol dimethyl ether, propylene Examples thereof include ethers such as glycol dimethyl ether, and ethyl glycolate derivatives such as methyl lactate and ethyl glycolate. The present invention is not limited to.

A coating material is prepared by the above-described method, and a solution material is applied on a substrate to be processed on which a resist pattern has been formed, for example, by a spin coating method or the like, and then the solvent is heated to evaporate the organic silicon. Create a membrane.

Next, the organic silicon film formed as described above is etched back.

As a method of etching back, a method of immersing in an organic silicon film diluting solvent, a method of exposing to plasma of oxygen or a halogen-based gas, a chemical mechanical polishing (CMP method)
There are.

The diluting solvent for the organic silicon film is as described above.
Solvents can be mentioned. In addition, halogen-based gas
As Cl_Two, HBr, Br_Two, HCl, etc.
CH_TwoF _Two, CHF_Three, CF_Four, C_FourF₈Floroka
And carbon gas.

Thereafter, only the resist pattern is removed. The following three methods are used to remove the resist pattern.
There are two ways.

(1) The resist film is heated to a temperature higher than the temperature at which the dissolution inhibiting group or dissolution inhibitor in the resist is decomposed. Thereafter, the resist film is immersed in a solution for dissolving the resist, thereby removing the resist film.

That is, when the chemically amplified positive resist is removed, the resist is first heated at a temperature higher than the temperature at which the dissolution inhibiting group or dissolution inhibitor is decomposed, and then dissolved with an alkaline solution. It is known that a dissolution inhibiting group or a dissolution inhibitor of a chemically amplified positive resist is decomposed by heating or the like in addition to a catalytic reaction by an acid. Therefore, if the dissolution inhibiting group or dissolution inhibitor in the resist is decomposed by heating and immersed in an alkaline solution, only the resist can be removed.

FIG. 3 shows a film thickness 60 formed on a Si substrate.
00 Å chemically amplified positive resist (using t-butoxycarbonylmethyl group as dissolution inhibiting group)
3 shows the heating temperature dependency (heating temperature of 60 seconds) of the amount of the remaining resist film after dipping in a 0.21 normal TMAH aqueous solution for 60 seconds.

As can be seen from the graph of FIG. 6, by heating the resist film to 155 ° C. or higher, which is the decomposition temperature of the t-butoxycarbonylmethyl group as a dissolution inhibiting group, the residual film after the development of the resist becomes 0%. Becomes The result is 155
It shows that the dissolution inhibiting group was sufficiently decomposed at ℃. That is, in order to remove the resist, heating may be performed at a temperature higher than the temperature at which the dissolution inhibiting group is decomposed.

However, if the temperature is too high, a cross-linking reaction may occur between the polymer resins depending on the type of the resist, and the solubility in the developing solution may decrease. Therefore, it is necessary to check in advance the change in the melting characteristics with respect to the heating temperature.

(2) After the resist pattern is subjected to irradiation, heating, or a combination thereof, the resist pattern is immersed in a solution for dissolving the resist to remove the resist pattern.

In this method, radiation is applied by Kr
F excimer laser (248 nm), ArF excimer laser (193 nm), mercury lamp i-line (365 n)
m), high-energy rays such as electron beams and X-rays. The irradiation dose of radiation needs to be larger than the irradiation dose in normal exposure.

The heating temperature varies depending on the type of the resist, but generally, about 80 to 200 ° C. is appropriate.

As the solution for dissolving the resist used in the above methods (1) and (2), an alkaline solution can be used. Examples of the alkali include inorganic alkalis such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, and sodium silicate; ethylamine;
-Primary amines such as propylamine, secondary amines such as diethylamine, tertiary amines such as triethylamine and methyldiethylamine, and secondary amines such as tetramethylammonium hydroxide (TMAH) and trimethylhydroxyethylammonium hydroxide. And quaternary ammonium salts.

(3) The resist pattern is removed using an organic solvent having selectivity to the organic silicon film. Such organic solvents include (a) at least one kind of solvent contained in the resist solution, (b) a surfactant, (c) 0.20
It is a solution containing any of the alkaline aqueous solutions having a higher concentration than the specified value. By impregnating the resist pattern with this organic solvent, it is possible to remove only the resist without removing the organic silicon film pattern.

More specifically, the following method is used. 1) Impregnating the resist pattern with a solution containing at least one of the solvents contained in the resist solution, and removing the resist pattern. The solution may contain a surfactant as shown in 2) below or an alkali solution as shown in 3) below.

2) A resist pattern is impregnated with a solution containing a surfactant. At this time, for example, a water-soluble organic solvent can be used. Examples of the water-soluble organic solvent include sulfoxides such as dimethyl sulfoxide having a hydrophobic alkyl group having 3 or more carbon atoms, sulfones such as dimethyl sulfone, amides such as N, N-dimethylformamide and N, N-dimethylacetamide. Lactams such as N-methyl-2-pyrrolidone; polyhydric alcohols such as ethylene glycol, ethylene glycol monomethyl ether, and ethylene glycol monomethyl ether acetate, and derivatives thereof;

As the surfactant to be contained, any of generally known anionic, cationic and nonionic surfactants may be used. Specific examples of the surfactant include the following. First, as anionics, there are alkylbenzenesulfonic acids, alkylnaphthalenesulfonic acids and the like. As the cationic type, there is a quaternary ammonium salt having 6 or more carbon atoms. Examples of the nonionic type include polyoxyethylene fatty acid esters and polyoxyethylene alkyl ethers. The solution may contain an aqueous alkaline solution as shown in 3) below.

3) Impregnate the resist pattern with a high-concentration aqueous alkali solution. Examples of the alkali include inorganic alkalis such as sodium hydroxide, potassium hydroxide, ammonia and sodium silicate; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine; triethylamine and methyldiethylamine. And quaternary ammonium salts such as tetramethylammonium hydroxide (TMAH) and trimethylhydroxyethylammonium hydroxide. It is desirable that the concentration of the aqueous alkali solution is high, for example, in the case of TMAH, it is preferably 0.3 N or more.

The temperature of each of the above solutions may be room temperature, but may be heated to a temperature not exceeding 150 ° C. for the purpose of shortening the impregnation time.

[0080]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 FIG. 1 is a sectional view showing a pattern forming method according to this embodiment in the order of steps. First, as shown in FIG. 1A, a 3000 Å-thick silicon oxide film (not shown) is formed on a substrate 1 to be processed by a sputtering method, and then a coating type organic antireflection film 2 (product) (CD9: Brewer Science) was applied to a thickness of 900 angstroms.

Next, a chemically amplified positive resist having a t-butoxycarbonyl group as a dissolution inhibiting group is applied,
Pre-baking was performed at 100 ° C. for 90 seconds on a hot plate to form a resist film having a thickness of 4000 Å.

Next, an excimer laser exposure apparatus NSR-
Using S201A (manufactured by Nikon Corporation), the resist film was irradiated with a line and space pattern through a mask by KrF excimer laser light.

Then, at 100 ° C. on a hot plate for 9 hours.
A post-exposure bake (PEB) for 0 second was performed, and the resist pattern 3 was formed by developing with a 0.21N aqueous solution of tetraammonium hydroxide (TMAH).

Thereafter, as shown in FIG. 1 (b), on the substrate 1 on which the antireflection film 2 and the resist pattern 3 are formed, the average molecular weight of 12,
000 organic silicon compounds (m / n = 4/1) 10 g
Is dissolved in 50 g of toluene, and a solution material prepared by applying the solution is applied. The solution is heated on a hot plate at 200 ° C. for 90 seconds to evaporate and dry the solvent, thereby forming an organic silicon film 4 having a thickness of 6000 Å in a flat portion. Formed.

In this step, the dissolution inhibiting group or dissolution inhibitor in the resist is decomposed.

Then, as shown in FIG. 1C, the organic silicon film was etched by chlorine gas plasma 5 using an RIE apparatus, and etched back to a thickness of 2000 angstroms.

Thereafter, the resist pattern 3 is set to 0.2
The resist pattern 3 was removed by immersing in a 1N aqueous solution of tetramethylammonium hydroxide at room temperature for 90 seconds. At this time, the organic silicon film did not deteriorate.

Subsequently, the processing of the anti-reflection film 2 was removed by etching using a plasma using CF ₄ and oxygen by using an RIE apparatus, thereby obtaining a mask pattern 6 as shown in FIG.

Embodiment 2 FIG. 2 is a sectional view showing a pattern forming method according to this embodiment in the order of steps. First, as shown in FIG. 2A, a 3000 Å-thick silicon oxide film (not shown) is formed on the substrate 11 to be processed by sputtering.
A coating type organic antireflection film 12 (trade name: CD9, manufactured by Brewer Science) was applied to a thickness of 900 Å.

Next, a chemically amplified positive resist having a t-butoxycarbonyl group as a dissolution inhibiting group is applied,
Pre-baking was performed at 130 ° C. for 90 seconds on a hot plate to form a resist film having a thickness of 4000 Å.

Next, an excimer laser exposure apparatus NSR-
Using S201A (manufactured by Nikon Corporation), the resist film was irradiated with a line and space pattern through a mask by KrF excimer laser light.

Then, at 100 ° C. on a hot plate for 9 hours.
A post-exposure bake (PEB) for 0 second was performed, and the resist pattern 13 was formed by developing with a 0.21N aqueous solution of tetraammonium hydroxide (TMAH).

Then, as shown in FIG. 2B, on the substrate 1 on which the antireflection film 2 and the resist pattern 3 are formed, the average molecular weight of 12
000 organic silicon compounds (m / n = 4/1) 10 g
Is dissolved in 50 g of toluene, and coated on a hot plate at 130 ° C. which is lower than the temperature at which the dissolution inhibiting group or dissolution inhibitor in the resist is decomposed.
The organic silicon film 14 is heated for 2 seconds to evaporate and dry the solvent, and the film thickness at the flat portion becomes 6000 Å.
Was formed.

Next, as shown in FIG. 2C, the organic silicon film 14 was etched by chlorine gas plasma 15 using an RIE apparatus, and etched back to a thickness of 2000 Å.

Then, as shown in FIG. 2D, the resist pattern 13 is subjected to KrF excimer exposure using a KrF excimer exposure apparatus.
The entire surface was exposed with an F excimer laser 16. here,
The exposure amount was set to 50 mJ / cm ^{2, which} is twice as large as that in normal exposure. It is desirable that the exposure environment has an oxygen concentration as low as possible.

Next, 90 ° C. on a hot plate at 110 ° C.
After baking for 2 seconds, the resist pattern 13 was removed by dipping in a 0.21N aqueous solution of tetramethylammonium hydroxide at room temperature for 90 seconds. At this time, the organic silicon film did not deteriorate.

Subsequently, the processing of the antireflection film 12 is removed by etching with a plasma using CF ₄ and oxygen using an RIE apparatus, and as shown in FIG. 1E, a mask pattern 17 made of an organic silicon compound is formed. I got

Example 3 A mask pattern was formed in the same manner as in Example 1 according to the process shown in FIG. First, as shown in FIG. 1A, a 3000 Å-thick silicon oxide film (not shown) is formed on a substrate 1 to be processed by a sputtering method, and then a coating type organic antireflection film 2 (product) (CD9: Brewer Science) was applied to a thickness of 900 angstroms.

Next, two types of resist films having a thickness of 4000 angstroms were formed by the following methods (A1) and (A2).

(A1): about 40% of t-butoxycarbonylated polyvinylphenol having an average molecular weight of 7,000 (15 g), triphenylfluphonium triflate 1
g was dissolved in 84 g of ethyl lactate (EL), and the pore size was 0.15.
The solution was filtered through a μm membrane filter to obtain a photoresist solution. Next, a photoresist solution was spin-coated on the antireflection film 12 to a thickness of 0.8 μm and baked on a hot plate at 130 ° C. for 90 seconds to form a resist film.

(A2): About 50% of t-butoxycarbonylated polyvinyl phenol (19 g) having an average molecular weight of 10,000 and triphenylfluphonium triflate (1.3 g) were mixed with 50 g of EL and ethyl-3-ethoxypropionate (EEP). ) Dissolved in 30 g of the mixed solution to give a pore size of 0.
The solution was filtered through a 15 μm membrane filter to obtain a photoresist solution. Next, a photoresist solution was spin-coated on the antireflection film 12 to a thickness of 0.85 μm and baked on a hot plate at 100 ° C. for 90 seconds to form a resist film.

Next, the above resist films (A1) and (A2) were applied to an excimer laser exposure apparatus NSR-S
201A (manufactured by Nikon Corporation) was used to irradiate a line and space pattern with a KrF excimer laser beam through a mask.

Then, at 100 ° C. for 9 hours on a hot plate.
A post-exposure bake (PEB) for 0 second was performed, and the resist pattern 3 was formed by developing with a 0.21N aqueous solution of tetraammonium hydroxide (TMAH).

Thereafter, as shown in FIG. 1 (b), on the substrate 1 on which the antireflection film 2 and the resist pattern 3 are formed, the average molecular weight of 12,
000 organic silicon compounds (m / n = 4/1) 10 g
Is dissolved in 50 g of cumene, and the resulting solution material is applied.
The film was heated on a hot plate at 130 ° C., which is lower than the temperature at which the dissolution inhibiting group or dissolution inhibitor in the resist decomposed, for 90 seconds, and the solvent was evaporated and dried.
An organic silicon film 4 having a thickness of 2,000 angstroms was formed.

Next, in FIG. 1C, the organic silicon film 4 was immersed in a cumene solution instead of being etched back by chlorine gas gas plasma, and was etched back to a thickness of 2,000 Å.

Thereafter, the resist pattern 3 was immersed in an organic solvent at room temperature for 90 seconds to remove the resist pattern 3. The type, temperature and time of the organic solvent at this time are shown in Tables 1 and 2 below.

[0108]

[Table 1]

[0109]

[Table 2]

The surface of the remaining organic silicon film pattern was observed with an optical microscope and an electron microscope, and the presence or absence of a resist residue was examined. Table 2 below shows the composition of the impregnated solution, the impregnation conditions, and the results of the evaluation of the presence or absence of the residue. In Table 2 below, the results were all “O”, that is, there was no resist residue.

Further, no deterioration or corrosion of the organic silicon film was observed.

[0112]

[Table 3]

Subsequently, the processing of the antireflection film 2 was removed by etching with a plasma of CF ₄ and oxygen using an RIE apparatus, and a mask pattern 6 was obtained.

Comparative Example The resist was removed by O ₂ ashing and immersion in an aqueous solution of sulfuric acid and hydrogen peroxide. As a result, the oxidation of the organic silicon compound occurred, and the etching resistance of the organic silicon compound to the silicon oxide film deteriorated.

Example 4 In Example 1, the structure shown in FIG. 1B was immersed in an aniline solution at room temperature for about 1 minute to remove the organic silicon film 4 from the surface by 2,000 Å. As a result, the same mask pattern as in Example 1 was obtained.

Example 5 In Example 1, the structure shown in FIG. 1B was etched by magnetron RIE under the following conditions to remove the organic silicon film 4 from the surface by 2,000 Å. As a result, the same mask pattern as in Example 1 was obtained.

Etching conditions Chlorine gas flow rate: 200 SCCM Pressure: 75 mTorr RF power: 200 W Temperature: 80 ° C. Etching time: 30 seconds

[0118]

As described above in detail, according to the present invention, the dissolution inhibiting group of the resist is formed by irradiation with ultraviolet light, X-ray, electron beam, ion beam, or the like, heat treatment, or a combination thereof. By decomposing and treating with an alkali developing solution or the like, it is possible to efficiently remove only the resist pattern without deteriorating the organic silicon film, thereby forming a mask pattern made of an organic silicon compound having excellent maskability. It is possible to obtain

[Brief description of the drawings]

FIG. 1 is a sectional view showing a pattern forming method according to an embodiment of the present invention in the order of steps.

FIG. 2 is a sectional view showing a pattern forming method according to another embodiment of the present invention in the order of steps.

FIG. 3 is a characteristic diagram showing a heating temperature dependency of a resist remaining film amount.

[Description of Signs] 1,11: Substrate to be processed 2,12 ... Anti-reflection film 3,13 ... Resist pattern 4,14 ... Organic silicon film 5,15 ... Chlorine gas plasma 6,17 ... Mask pattern 16 ... KrF excimer laser

Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) H01L 21/306 D (72) Inventor Masafumi Asano 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Pref. 72) Inventor Yasuo Miyoshi 8 Shinsugita-machi, Isogo-ku, Yokohama-shi, Kanagawa F-term (reference) 2H096 AA25 BA01 BA09 BA20 CA20 EA02 EA04 EA05 EA06 EA07 GA08 HA23 HA30 JA04 LA01 LA02 LA03 5F043 CC12 CC16 DD07 DD15 DD30 GG10 5F046 CA01 CA04 MA01 MA02 MA03 MA04 5F058 AC03 AC06 AC08 AF04 AG01 AG04 AG10 AH10

Claims (5)

[Claims] A step of forming a resist pattern on a substrate to be processed; a step of embedding an organic silicon compound having a silicon-silicon bond in a main chain in an opening of the resist pattern; A step of heating to a temperature not lower than the temperature at which the dissolution inhibiting group or the dissolution inhibiting agent therein is decomposed; A pattern forming method comprising: 2. A step of forming a resist pattern on a substrate to be processed; a step of embedding an organic silicon compound having a bond of silicon and silicon in a main chain in an opening of the resist pattern; Radiation irradiation, heating, or a combination thereof, and a step of immersing the resist pattern in a solution for dissolving the resist, removing the resist pattern, and forming an organic silicon film pattern. Characteristic pattern forming method 3. A step of forming a resist pattern on a substrate to be processed; a step of embedding an organic silicon compound having a bond of silicon and silicon in a main chain in an opening of the resist pattern; At least one of the solvents
At least one selected from the group consisting of (b) a surfactant, and (c) an aqueous alkali solution having a concentration higher than 0.20 N.
Dipping the resist pattern in a solution containing a seed to remove the resist pattern and form an organic silicon film pattern. 4. The step of embedding an organosilicon compound having a silicon-silicon bond in the main chain in the opening of the resist pattern, wherein the silicon-silicon bond is formed on the entire surface of the substrate on which the resist pattern is formed. The pattern forming method according to any one of claims 1 to 3, wherein the organic silicon compound is applied by applying the organic silicon compound and then etching back the organic silicon compound. 5. The etching back is performed by one selected from the group consisting of a method of immersing the organic silicon compound in a diluting solvent, a method of exposing to a plasma of oxygen or a halogen-based gas, and a chemical mechanical polishing. The pattern forming method according to claim 4, wherein: