JPH09102458A - Pattern formation and surface treatment agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent formation of a refractory layer in a resist pattern surface by forming a resist film in a surface of a semiconductor board whose surface is treated by a specified silane compound and forming a resist pattern by development after exposure by using a mask having a desired pattern configuration to the resist film. SOLUTION: A surface of a semiconductor substrate 1 is treated by a surface treatment agent containing silane compound expressed by R<1> 4-n Si(OR)n . In the formula, (n) is an integer of 1 to 3 and R is a 1 to 6C substitutional saturated hydrocarbon group or non-substitutional saturated hydrocarbon group. Chemical amplification type resist is applied to a surface of the semiconductor substrate 1 whose surface is treated and a resist film is formed. After exposure by using a mask having a desired pattern configuration to the resist film, development is carried out and a resist pattern 2 is formed. Thereby, a refractory layer is not formed in a surface part of the resist pattern 2 and adhesion between the semiconductor substrate 1 and the resist pattern 2 can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pattern forming method for forming a resist pattern on a semiconductor substrate in a semiconductor device manufacturing process, and a surface treating agent used in the resist pattern forming step.

[0002]

2. Description of the Related Art In recent years, with the increase in the density and integration of semiconductor devices, the necessity of fine processing technology has been increasing more and more.

As a first measure for enabling fine processing in a lithography process, DUV light using an excimer laser as a light source or short wavelength light such as EB or X-ray is used as exposure light and acid is used as a resist. A technique for forming a resist pattern composed of a chemically amplified resist that utilizes generation is being developed (“Coloring Material”, Vol. 67).
No. 7, pp 446-455 (1994)).

Hereinafter, referring to FIGS. 12 and 13,
As a first conventional example, a pattern forming method using a chemically amplified resist will be described.

FIG. 12 shows a process flow of a pattern forming method according to a first conventional example, and FIG. 13 shows a surface state of a semiconductor substrate formed by the pattern forming method according to the first conventional example.

First, hexamethyldisilazane (hereinafter, abbreviated as HMDS) as a surface treatment agent is supplied to the surface of the semiconductor substrate 1 made of silicon to make the surface of the semiconductor substrate 1 hydrophobic so that the semiconductor substrate 1 is made hydrophobic. 1. Adhesion is improved. This treatment is performed by bubbling liquid HMDS with nitrogen gas and then spraying HMDS onto the surface of the semiconductor substrate 1 heated to 60 ° C. for 30 seconds, as shown in FIG. In this case, FIG.
As shown in (b), H of the OH group on the surface of the semiconductor substrate 1
Is replaced by Si (CH ₃ ) ₃ (trimethylsilyl group), the surface of the semiconductor substrate 1 becomes hydrophobic, the adhesion of the semiconductor substrate 1 is improved, and NH ₃ (ammonia) is generated.

Next, after a chemically amplified resist is applied to the surface of the semiconductor substrate 1 to form a resist film, the resist film is exposed using a desired mask, and then a post exposure bake (hereinafter, referred to as "exposure bake"). Abbreviated as PEB.)
And development are sequentially performed to form a resist pattern.

As a second measure for enabling fine processing in the lithography process, Japanese Patent Laid-Open No. 58-1881.
As disclosed in Japanese Patent Publication No. 32, a technique for improving the adhesion between a semiconductor substrate and a resist pattern has been proposed.

A pattern forming method using a resist containing, for example, a phenolic resin will be described below as a second conventional example.

First, on the surface of a semiconductor substrate made of silicon, the general formula: R ¹ SiX _3-n R ² _n (where n is 0, 1
Or 2, X is a halogen or an —OR ′ group (R ′ is an alkyl group having 1 to 3 carbon atoms), and R ¹ is CH ₂ ═CH.
-, ZCH ₂ - (Z is halogen) or

Embedded image And R ² is hydrogen or an alkyl group having 1 to 3 carbon atoms. The surface treatment agent containing the silane compound represented by the formula (1) is supplied to make the surface of the semiconductor substrate hydrophobic, thereby improving the adhesion of the semiconductor substrate.

Next, a resist containing, for example, phenol resin is applied to the surface of the semiconductor substrate to form a resist film, and then the resist film is exposed using a desired mask, and then PEB and development are performed. Are sequentially performed to form a resist pattern.

[0012]

FIG. 14 and FIG. 15 show
1 shows a schematic cross-sectional shape of a resist pattern 2 formed on a semiconductor substrate 1 made of silicon or a semiconductor substrate 5 made of BPSG by a pattern forming method according to a first conventional example. 14 and 15 show a positive chemically amplified resist (manufactured by Japan Synthetic Rubber Co., Ltd., KR) on a semiconductor substrate 1 made of silicon or a semiconductor substrate 5 made of BPSG.
F K2G) is applied to a film thickness of 0.7 μm, and then NA:
Exposure by 0.5 KrF excimer laser stepper, then PEB is carried out for 90 seconds at a temperature of 100 ° C., and development is carried out using a 2.38 wt% tetramethylammonium hydroxide aqueous solution of 0.25 μm line. -The cross-sectional shape of the and-space pattern is shown.

According to the first conventional example, the insoluble layer 3 is formed on the surface portion of the resist pattern 2 as shown in FIG. 14, or the bottom portion of the resist pattern 2 is formed at the bottom portion as shown in FIG. 4 is formed. Despite the use of the same pattern forming method, the insolubilized layer 3 is formed on the surface of the resist pattern 2 or the bottom portion 4 is formed on the bottom of the resist pattern 2 because of the atmosphere at the time of pattern formation. Or, it is considered that the surface condition of the substrate is different.

The insoluble layer 3 is formed on the surface of the resist pattern 2.
If the ridges are formed or the bottom portion 4 is formed on the bottom of the resist pattern 2, the post-process is adversely affected, which causes a decrease in the yield of the semiconductor device, which is a first problem.

Further, the resist pattern formed on the semiconductor substrate by the pattern forming method according to the second conventional example is treated with the above-mentioned surface treatment agent on the surface of the semiconductor substrate. Although the adhesiveness with the resist pattern is improved as compared with the conventional one, there is a second problem that the adhesiveness is not satisfactory when further fine processing is performed in the lithography process. That is, for example, pattern formation of 0.30 μm or less by i-line exposure, 0.25 μm by KrF excimer laser exposure
In the following pattern formation and pattern formation of 0.20 μm or less by ArF excimer laser exposure, pattern peeling may occur.

In view of the above, the first object of the present invention is to prevent the insolubilized layer from being formed on the surface portion of the resist pattern, and to prevent the bottoming portion from being formed on the bottom portion of the resist pattern. A third purpose is to further improve the adhesion between the semiconductor substrate and the resist pattern.

[0017]

Means for Solving the Problems The present inventors have conducted various studies on the cause of the formation of the hardly soluble layer on the surface of the resist pattern, and as a result, have found that the alkali component is responsible. That is, when an alkaline component is present on the surface of the resist pattern, the acid generated by exposure is deactivated to form a surface insolubilized layer, and the surface portion of the resist pattern has a T-top shape. This means
It is reported that the pattern may not be resolved when there are many alkaline components (SAMacDonald et al., Proc.SPIE, vol.1).
466, p.2 (1991)).

In order to investigate the cause of generation of the ammonia component as an alkaline component which adversely affects the chemically amplified resist, impurities in the environment were analyzed in a clean room. As shown in FIG. 16, it was a decomposition product of HMDS. It was found that there was a positive correlation between the environmental concentrations of trimethylsilanol and ammonia. From this, it is presumed that the alkali component which adversely affects the shape of the pattern of the chemically amplified resist is caused by HMDS which is a surface treatment agent for a semiconductor substrate.

Further, the inventors of the present invention have conducted various studies on the cause of the formation of the bottom portion at the bottom of the resist pattern, and as a result, when there are atoms having unpaired electrons on the surface portion of the semiconductor substrate, they are exposed to light. It was found that the generated acid was deactivated to form a skirt. Examples of the atom having an unpaired electron include a phosphorus atom in a semiconductor substrate made of BPSG, and a nitrogen atom in a semiconductor substrate made of TiN or SiN.

The first invention of the present invention was made on the basis of the former knowledge, and uses a surface treatment agent containing a silane compound represented by the following general formula (8) in place of the conventional HMDS. Therefore, the alkaline component is prevented from being generated on the surface of the semiconductor substrate.

[0021] Specifically, as a solving means devised by the invention of claim 1, the pattern forming method is that the surface of the semiconductor substrate is surface-treated with a surface treating agent containing a silane compound represented by the following general formula (8). A first step, a second step of applying a chemically amplified resist to the surface of the surface-treated semiconductor substrate to form a resist film, and a mask having a desired pattern shape for the resist film After exposure
And a third step of developing to form a resist pattern.

R ¹ _4-n Si (OR) _n (8) where n is an integer of 1 to 3 and R is 1 to 6 carbon atoms.
A substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group,
A substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkylcarbonyl group having 1 to 6 carbon atoms, wherein R ¹ is the same or different; A hydrogen atom, a substituted or unsubstituted saturated hydrocarbon group having 1 to 6 carbon atoms, a substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or 3 to 6 alicyclic saturated hydrocarbon groups.

According to the structure of claim 1, since the semiconductor substrate is surface-treated with the surface treatment agent containing the silane compound represented by the general formula (8), no alkali component is generated on the surface of the semiconductor substrate after the surface treatment.

The invention of claim 2 limits the chemically amplified resist in the second step of claim 1 to one containing an acid generator and a resin which becomes alkali-soluble by the action of an acid. .

According to a third aspect of the present invention, the chemically amplified resist in the second step of the first aspect contains an acid generator, an alkali-soluble resin, and a compound or resin which becomes alkali-soluble by the action of an acid. It is limited to.

According to a fourth aspect of the present invention, the chemically amplified resist in the second step of the first aspect contains an acid generator, an alkali-soluble resin, and a compound or resin that causes a crosslinking reaction by the action of an acid. It is limited to one.

The second invention of the present invention was made on the basis of the latter knowledge. Instead of the conventional HMDS, the following general formula (9), (10), (11) or (12) is used. By using the surface treatment agent containing the silane compound shown, a hydrocarbon group layer is formed between the atom having an unpaired electron existing on the surface of the semiconductor substrate and the chemically amplified resist. As a result, the footing shape of the resist pattern can be significantly improved.

Specifically, the means for solving the problems according to the invention of claim 5 is a pattern forming method, in which the surface of a semiconductor substrate is represented by the following general formula (9), (10), (11) or (12). A first step of performing a surface treatment with a surface treatment agent containing a silane compound, and a second step of applying a chemically amplified resist to the surface of the surface-treated semiconductor substrate to form a resist film
And a third step of exposing the resist film using a mask having a desired pattern shape and developing the resist film to form a resist pattern.

R ² R ¹ _3-n Si (OR) _n (9) where n is an integer of 1 to 3 and R is 1 to 6 carbon atoms.
A substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group,
A substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group having 1 to 6 carbon atoms or an unsubstituted alkylcarbonyl group, and R ¹ is the same or different. There, a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a carbon number It is an alicyclic saturated hydrocarbon group having 3 to 6 and R ₂ is a substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, having 3 to 6 carbon atoms.
It is a C6 substituted unsaturated hydrocarbon group or an unsubstituted unsaturated hydrocarbon group, or a C3-C6 alicyclic saturated hydrocarbon group.

R ² R ¹ _3-n Si (NR ³ ₂ ) _n (10) wherein n is an integer of 1 to ³ and R ³ is the same or different and is a hydrogen atom or It is an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ¹ is the same or different and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, and carbon number. 1 to 6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or carbon number 3
To 6 alicyclic saturated hydrocarbon groups, R ² has 3 carbon atoms
~ 6 substituted saturated hydrocarbon group or unsubstituted saturated hydrocarbon group, C3-6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C3-6 alicyclic saturated carbon group It is a hydrogen group.

(R ² R ¹ ₂ Si) ₂ NR ³ (11) However, R ³ is a hydrogen atom or an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, and R ¹ is the same or different. And a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsaturated unsaturated hydrocarbon group, or carbon Number 3
To 6 alicyclic saturated hydrocarbon groups, R ² has 3 carbon atoms
~ 6 substituted saturated hydrocarbon group or unsubstituted saturated hydrocarbon group, C3-6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C3-6 alicyclic saturated carbon group It is a hydrogen group.

[0032]

Embedded image However, in the formula, m is an integer of 2 to 6, R ³ is a hydrogen atom or an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, and R ^{1 is}
Is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or 3 carbon atoms. a 6 alicyclic saturated hydrocarbon group, R ² is a substituted saturated hydrocarbon group or a non-substituted saturated hydrocarbon group having 3 to 6 carbon atoms, a substituted 3 to 6 carbon atoms unsaturated hydrocarbon group or non It is a substituted unsaturated hydrocarbon group or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms.

According to the structure of claim 5, the surface of the semiconductor substrate is formed on the surface of the general formula (9), (10), (11) or (1).
When the surface treatment is performed with the surface treatment agent containing the silane compound shown in 2), a hydrocarbon group layer forms a space between the atom having unpaired electrons existing on the surface of the semiconductor substrate and the chemically amplified resist. Therefore, it becomes difficult for the acid generated from the chemically amplified resist to react with the unpaired electrons on the surface of the semiconductor substrate, and the bottom shape of the resist pattern is significantly improved.

R ² in the above general formulas (9) to (12), that is, a substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated carbon group having 3 to 6 carbon atoms. A hydrogen group or an unsubstituted unsaturated hydrocarbon group, or
When the surface treatment of the semiconductor substrate is performed with the surface treatment agent containing a silane compound having an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms, the hydrophobicity of the semiconductor substrate surface is also improved. This is also a factor that makes it difficult for the acid generated from the chemically amplified resist to react with the unpaired electrons on the surface of the semiconductor substrate, thereby significantly improving the bottom shape of the resist pattern.

Further, a substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group represented by the above general formula (10), (11) or (12) and a substituted unsaturated group having 3 to 6 carbon atoms. When a semiconductor substrate is surface-treated with a surface-treating agent containing a silane compound having a hydrocarbon group or an unsubstituted unsaturated hydrocarbon group, or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms, a by-product ( Ammonia, dialkylamine, etc.) needs to be removed to the outside of the system, but the surface treatment capacity for the semiconductor substrate is equivalent to that of the silane compound represented by the above general formula (9). A layer of hydrocarbon radicals is reliably formed between the atoms with the existing unpaired electrons and the chemically amplified resist.

FIG. 11 (a) is a diagram for explaining the contact angle: θ that is a measure of hydrophobicity, and FIG. 11 (b) shows the relationship between the number of x and the contact angle: θ in (Formula 4). Figure,
Specifically, after bubbling the surface treatment agent with nitrogen gas, 3 is applied to the surface of the semiconductor substrate heated to 120 ° C.
It is the result when spraying for 0 seconds.

[0037]

Embedded image

As is apparent from FIG. 11B, x is 2
Above, that is, when the number of carbon atoms in the hydrocarbon group is 3 or more,
Since the contact angle: θ is significantly increased, the hydrophobicity of the semiconductor substrate surface is improved.

The inventions of claims 6 to 8 are based on such findings, and the above general formula (9) is such that at least one of the hydrocarbon groups substituting on the Si atom has 3 or more carbon atoms. , (10), (11) or (12).

The invention of claim 6 limits the chemically amplified resist in the second step of claim 5 to one containing an acid generator and a resin which becomes alkali-soluble by the action of an acid. .

According to a seventh aspect of the present invention, the chemically amplified resist in the second step of the fifth aspect contains an acid generator, an alkali-soluble resin, and a compound or resin which becomes alkali-soluble by the action of an acid. It is limited to.

According to an eighth aspect of the present invention, the chemically amplified resist in the second step of the fifth aspect contains an acid generator, an alkali-soluble resin, and a compound or resin that causes a crosslinking reaction by the action of an acid. It is limited to one.

A third aspect of the present invention is a surface treatment containing a silane compound represented by the following general formula (13) when various experiments are performed on the surface treatment agent in the pattern forming method according to the first aspect. It was found that the surface treatment of the semiconductor substrate with the agent improves the adhesion between the semiconductor substrate and the resist pattern, and was made based on this finding.

Specifically, as a solving means devised by the invention of claim 9, the pattern forming method is that the surface of the semiconductor substrate is surface-treated with a surface-treating agent containing a silane compound represented by the following general formula (13). A first step, a second step of applying a resist to the surface of the surface-treated semiconductor substrate to form a resist film, and a step of exposing the resist film using a mask having a desired pattern shape And a third step of developing to form a resist pattern.

R ¹ _4-n Si (OR ⁴ ) _n (13) where n is an integer of 1 to 3 and R ⁴ has 1 to 1 carbon atoms.
A substituted saturated hydrocarbon group having 6 carbon atoms, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group having 1 to 6 carbon atoms or an unsubstituted alkylcarbonyl group, R ¹ is the same or different and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated group. A hydrocarbon group, or
It is an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms.

In the structure of claim 9, the above general formula (1
In the silane compound represented by 3), R ⁴ is a substituted saturated hydrocarbon group having 1 to 6 carbon atoms, a substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or carbon. A silane compound which is either a substituted alkylcarbonyl group or an unsubstituted alkylcarbonyl group of the formulas 1 to 6 is preferable. The reason is as follows. The halogen group, unsaturated bond, carbonyl group, or the like present in the chemical structure of R ⁴ dilutes the electron density on the Si atom and increases the acidity, thereby increasing the reactivity with the substrate. In other words, the processing ability of the substrate as a surface treatment agent becomes high,
It can be said to be a more preferable surface treatment agent because it improves the hydrophobicity of the substrate. The contact angle of the substrate after processing is mentioned as an index of the processing capacity, and the larger the contact angle, the higher the processing capacity. Table 1 shows the relationship between the silane compound contained in the surface treatment agent and the contact angle. Silane compounds represented by the above general formula (13) (Examples 1, 2, 3, 4 in (Table 1))
It can be seen that a large contact angle can be obtained by using. Note that (Table 1) shows the contact angle when the surface treatment agent was bubbled with nitrogen gas and sprayed on the surface of the semiconductor substrate heated to 120 ° C. for 30 seconds.

[0047]

[Table 1]

According to a tenth aspect of the invention, the resist in the second step of the ninth aspect is limited to one containing a naphthoquinonediazide compound and a novolac resin.

According to the eleventh aspect of the present invention, a surface treatment agent for treating the surface of a semiconductor substrate contains a silane compound represented by the following general formula (14).

[0050] _{^{R 1 4-n Si (OR}} ) n ...... (14) where, n in the formula is an integer of 1 to 3, R represents 1 to 6 carbon atoms
A substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group,
A substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkylcarbonyl group having 1 to 6 carbon atoms, wherein R ¹ is the same or different; A hydrogen atom, a substituted or unsubstituted saturated hydrocarbon group having 1 to 6 carbon atoms, a substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or 3 to 6 alicyclic saturated hydrocarbon groups.

[0051]

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(First Embodiment) The first embodiment realizes the above-described first invention.

The pattern forming method according to the first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows the process flow of the pattern forming method according to the first embodiment, and FIG. 2 shows the surface state of the semiconductor substrate when the surface treatment is performed with the surface treatment agent according to the first embodiment. FIG. 3 shows a schematic cross-sectional shape of a pattern formed on a semiconductor substrate surface-treated with the surface-treatment agent according to the first embodiment.

First, as shown in FIG. 2A, isopropenoxytrimethylsilane (hereinafter abbreviated as IPTMS) as a surface treatment agent is supplied to the surface of the semiconductor substrate 1 made of silicon (that is, IPTMS). Bubbling IPTMS with nitrogen gas and spraying it on the surface of the semiconductor substrate heated to 60 ° C. for 30 seconds) to make the surface of the semiconductor substrate 1 hydrophobic and improve the adhesion of the semiconductor substrate 1. By doing so, as shown in FIG. 2B, H of the OH group on the surface of the semiconductor substrate 1 is replaced with Si (CH ₃ ) ₃ (trimethylsilyl group), and (CH ₃ ) ₂ CO (acetone) is obtained.
Is generated.

Next, a chemically amplified resist is applied to the surface of the semiconductor substrate 1 and then exposed using a desired mask, and then PEB and development are sequentially performed to form a pattern.

When the pattern is formed as described above,
As shown in FIG. 3, the hardly-solubilized layer is not formed on the surface of the resist pattern 2. That is, FIG. 3 shows the semiconductor substrate 1
A positive chemically amplified resist (KRF K2G, manufactured by Japan Synthetic Rubber Co., Ltd.) was applied on the above to a film thickness of 0.7 μm, and then exposed by a KrF excimer laser stepper with NA: 0.5, and then PEB was applied. The cross-sectional shape of a 0.25 μm line-and-space pattern is shown when the development is carried out at a temperature of 100 ° C. for 90 seconds and the development is performed using a 2.38 wt% tetramethylammonium hydroxide aqueous solution.

As described above, according to the first embodiment,
Since IPTMS is used as the surface treatment agent, the surface of the semiconductor substrate 1 can be made hydrophobic without generating ammonia, so that it is possible to prevent the formation of the hardly soluble layer on the surface portion of the resist pattern and to stabilize the surface. The resist pattern shape can be obtained.

(Second Embodiment) The second embodiment also realizes the above-described first invention.

The pattern forming method according to the second embodiment of the present invention will be described below with reference to FIGS.

FIG. 4 shows the process flow of the pattern forming method according to the second embodiment, and FIG. 5 shows the surface state of the semiconductor substrate when the surface treatment is performed with the surface treatment agent according to the second embodiment. FIG. 6 shows a schematic cross-sectional shape of a pattern formed on a semiconductor substrate surface-treated with the surface-treatment agent according to the second embodiment.

First, as shown in FIG. 5A, acetoxytrimethylsilane (hereinafter abbreviated as ATMS) as a surface treatment agent is applied to the surface of the semiconductor substrate 1 made of silicon.
Is supplied (that is, ATMS is bubbled with nitrogen gas, and 3 is applied to the surface of the semiconductor substrate heated to 60 ° C.).
After spraying for 0 seconds), the surface of the semiconductor substrate 1 is made hydrophobic to improve the adhesion of the semiconductor substrate 1. By doing so, as shown in FIG. 5B, H of the OH group on the surface of the semiconductor substrate 1 is changed to Si (CH ₃ ) ₃ (trimethylsilyl group).
To produce CH ₃ COOH (acetic acid).

Next, a chemically amplified resist is applied to the surface of the semiconductor substrate 1 and then exposed using a desired mask, and then PEB and development are sequentially performed to form a pattern.

When the pattern is formed as described above,
As shown in FIG. 6, the hardly soluble layer is not formed on the surface portion of the resist pattern 2. That is, FIG. 6 shows the semiconductor substrate 1
A positive chemically amplified resist (KRF K2G, manufactured by Japan Synthetic Rubber Co., Ltd.) was applied on the above to a film thickness of 0.7 μm, and then exposed by a KrF excimer laser stepper with NA: 0.5, and then PEB was applied. The cross-sectional shape of a 0.25 μm line-and-space pattern is shown when the development is carried out at a temperature of 100 ° C. for 90 seconds and the development is performed using a 2.38 wt% tetramethylammonium hydroxide aqueous solution.

As described above, according to the second embodiment,
Since ATMS is used as the surface treatment agent, the surface of the semiconductor substrate 1 can be made hydrophobic without generating ammonia, so that it is possible to prevent the formation of the hardly soluble layer on the surface portion of the resist pattern and to stabilize the surface. The resist pattern shape can be obtained.

As the surface treatment agent, in the first embodiment, one that produces acetone as a reaction decomposition product,
In the second embodiment, the one that produces acetic acid as the reaction decomposition product and the one that produces the trimethylsilyl group as the substance that makes the surface of the semiconductor substrate hydrophobic are used. Not limited. That is,
A surface treatment agent containing a silane compound represented by the following general formula (15) can be used.

R ¹ _4-n Si (OR) _n (15) where n is an integer of 1 to 3 and R is a carbon number of 1 to 6
A substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group,
A substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkylcarbonyl group having 1 to 6 carbon atoms, wherein R ¹ is the same or different; A hydrogen atom, a substituted or unsubstituted saturated hydrocarbon group having 1 to 6 carbon atoms, a substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or 3 to 6 alicyclic saturated hydrocarbon groups.

As a first example of the silane compound represented by the general formula (15), a compound represented by the following general formula (16) can be mentioned.

[0068] R ¹ ₃ SiOR ...... (16) where the meaning of R and R ¹ are the above general formula (1
Same as 5).

The silane compound represented by the above general formula (16) has a single hydrolyzable group on the Si atom, and the semiconductor substrate is processed into a monomolecular film so that the in-plane uniformity is high. A film is obtained. Further, the silane compound represented by the general formula (16) is easily affected by the steric hindrance of the R ¹ substituent, and this property is reflected in the reaction rate (processing ability).

Specific examples of the silane compound represented by the above general formula (16) include compounds represented by (formula 5) and (formula 6).

[0071]

Embedded image

Embedded image

As a second example of the silane compound represented by the general formula (15), a compound represented by the following general formula (17) can be given.

R ¹ ₂ Si (OR) ₂ (17) However, the meanings of R and R ¹ are as shown in the general formula (1) above.
Same as 5).

The silane compound represented by the general formula (17) has high hydrolyzable groups when the number of hydrolyzable groups on the Si atom is two and the semiconductor substrate is processed into a laminated film.

Specific examples of the silane compound represented by the above general formula (17) include compounds represented by the chemical formula (7).

[0076]

Embedded image

As a third example of the silane compound represented by the general formula (15), a compound represented by the following general formula (18) can be given.

R ¹ Si (OR) ₃ (18) However, as for the meaning of R and R ¹ , the above general formula (1)
Same as 5).

The silane compound represented by the above general formula (17) has three hydrolyzable groups on the Si atom and is processed into a laminated film on the semiconductor substrate. The reactive silane compound may be hydrolyzed by moisture in the air to form a gel, which may cause particle contamination depending on the treatment method.

Specific examples of the silane compound represented by the above general formula (18) include compounds represented by the chemical formula (8).

[0081]

Embedded image

When an experiment similar to that of the first embodiment was conducted using the silane compounds represented by the above (Chemical formula 5), (Chemical formula 6), (Chemical formula 7) and (Chemical formula 8), (Table 2) As shown in (Table 3) and (Table 4), good results were obtained.

The silane compound represented by the general formula (16) is particularly stable in terms of material, and the silane compound represented by the general formula (1)
The silane compound represented by 8) is characterized by having a particularly high reactivity.

[0084]

[Table 2]

[Table 3]

[Table 4]

In the first and second embodiments, as the chemically amplified resist, a two-component system chemically amplified positive resist (KRF) containing an acid generator and a resin which becomes alkali-soluble by the action of acid is used. K2G) was used,
Instead, a three-component chemically amplified positive resist containing an acid generator, an alkali-soluble resin, and a compound or resin which becomes alkali-soluble by the action of an acid may be used. As a two-component chemically amplified positive resist,
For example, TDUR-DP007 manufactured by Tokyo Ohkasha may be used. As a three-component chemically amplified positive resist,
For example, DX561 and DX981 manufactured by Hoechst Inc. may be mentioned.

Further, as the chemically amplified resist, a three-component chemically amplified negative resist containing an acid generator, an alkali-soluble resin, and a compound or resin that causes a crosslinking reaction by the action of acid may be used. Examples of the three-component chemically amplified negative resist include X-ray manufactured by Shipley Co., Ltd.
P-8843, SAL-601 and the like. Even in such a chemically amplified negative resist, when an alkali component is generated at the time of surface treatment, the film thickness of the pattern is reduced due to deactivation of an acid, and the shape of the resist pattern is deteriorated.
According to the method of the present invention, since the deactivation of the acid can be prevented, a good pattern can be formed.

Since the chemically amplified resist is affected by the alkaline component regardless of its constitution or constituent components, the first and second embodiments are effective for all chemically amplified resists.

Hereinafter, examples of the constituent components of the above chemically amplified resist will be given, but the constituent components are not limited to the following.

<Two-component chemically amplified positive resist> Resin that becomes alkali-soluble by the action of acid: poly (t-
Butoxycarbonyloxystyrene-co-hydroxystyrene) Poly (t-butoxycarbonylmethyloxystyrene-co-
Hydroxystyrene) Poly (tetrahydropyranyloxystyrene-co-hydroxystyrene) Acid generator: onium salt, nitrobenzyl sulfonic acid ester compound <3-component chemically amplified positive resist> Alkali-soluble resin: polyvinylphenol , Polymethacrylic acid ○ Resin or compound that becomes alkali-soluble by the action of acid …… Poly (t-butoxycarbonyloxystyrene-co-hydroxystyrene) Poly (t-butoxycarbonylmethyloxystyrene-co-
Hydroxystyrene) Poly (tetrahydropyranyloxystyrene-co-hydroxystyrene)

Embedded image ○ Acid generator …… Onium salt, nitrobenzyl sulfonic acid ester compound <Three-component chemically amplified negative resist> ○ Alkali-soluble resin …… Polyvinylphenol, polymethacrylic acid ○ Compound or resin that causes cross-linking reaction by the action of acid ......
Melamine compound, melamine resin ○ Acid generator: onium salt, nitrobenzyl sulfonate compound (Third Embodiment) The third embodiment realizes the second invention described above.

The pattern forming method according to the third embodiment of the present invention will be described below with reference to FIGS. 7 and 8.

FIG. 7 shows the surface condition of the semiconductor substrate when the surface treatment with the surface treatment agent of the third embodiment is performed, and FIG. 8 shows the surface treatment with the surface treatment agent according to the third embodiment. The schematic cross-sectional shape of the pattern formed on the semiconductor substrate is shown.

First, as shown in FIG. 7A, BPSG
Isopropenoxy-n-hexyldimethylsilane (hereinafter, referred to as I
Abbreviated as PHDMS. ) Is supplied (ie, IPH
Bubbling DMS with nitrogen gas and spraying on the surface of the semiconductor substrate heated to 120 ° C. for 30 seconds) to form a hydrocarbon-based layer on the surface of the semiconductor substrate 5.
The hydrophobicity of the surface of the semiconductor substrate 5 is improved. This also improves the adhesion of the semiconductor substrate 5. As shown in FIG. 7B, H of the OH group on the surface of the semiconductor substrate 5 is Si (C
H ₃ ) ₂ (CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ ) is substituted to produce (CH ₃ ) ₂ CO (acetone).

Next, a chemically amplified resist is applied to the surface of the semiconductor substrate 5 to form a resist film, and then the resist film is exposed using a desired mask, and then PE is applied.
B and development are sequentially performed to form a pattern.

When the pattern is formed as described above,
As shown in FIG. 8, the bottom portion is not formed on the surface portion of the resist pattern 6. That is, FIG. 8 shows the semiconductor substrate 5
A positive chemically amplified resist (KRF K2G, manufactured by Japan Synthetic Rubber Co., Ltd.) was applied on the above to a film thickness of 0.7 μm, and then exposed by a KrF excimer laser stepper with NA: 0.5, and then PEB was applied. The cross-sectional shape of the 0.25 μm line-and-space pattern is shown when the development is carried out at a temperature of 100 ° C. for 90 seconds and the development is performed using a 2.38 wt% tetramethylammonium hydroxide aqueous solution.

As described above, according to the third embodiment,
Since IPHDMS is used as the surface treatment agent, a hydrocarbon group layer can be formed on the surface of the semiconductor substrate 5 and the hydrophobicity of the surface of the semiconductor substrate 5 can be improved. It is possible to prevent the formation of the pulling portion and obtain a stable resist pattern shape.

In the third embodiment, since the surface treatment agent which does not generate ammonia is used as the reaction decomposition product, the effect of preventing the formation of the hardly soluble layer on the surface portion of the resist pattern 6 can be obtained. To be On the other hand, when a resist pattern made of a chemically amplified resist is formed after the surface treatment using a surface treatment agent that generates ammonia as a reaction decomposition product, a poorly soluble layer is formed on the surface portion of the resist pattern 6. However, it is possible to prevent the bottom portion from being formed at the base of the resist pattern 6.

As the surface treatment agent capable of forming a hydrocarbon group layer on the surface of the semiconductor substrate and rendering the surface of the semiconductor substrate hydrophobic, it is preferable to use one containing a silane compound represented by the following general formula (19). it can.

R ² R ¹ _3-n Si (OR) _n (19) where n is an integer of 1 to 3 and R is a carbon number of 1 to 6
A substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group,
A substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group having 1 to 6 carbon atoms or an unsubstituted alkylcarbonyl group, and R ¹ is the same or different. There, a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a carbon number It is an alicyclic saturated hydrocarbon group having 3 to 6 and R ₂ is a substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, having 3 to 6 carbon atoms.
It is a C6 substituted unsaturated hydrocarbon group or an unsubstituted unsaturated hydrocarbon group, or a C3-C6 alicyclic saturated hydrocarbon group.

Examples of the silane compound represented by the above general formula (19) include those represented by the following general formula (20), (21) or (22).

R ² R ¹ ₂ SiOR (20) R ² R ¹ Si (OR) ₂ (21) R ² Si (OR) ₃ (22) (where R is 1 to 1 carbon atoms) 6-substituted saturated hydrocarbon group or unsubstituted saturated hydrocarbon group, C 1-6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C 1-6 substituted alkylcarbonyl group or non- A substituted alkylcarbonyl group, R ¹ is the same or different and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated carbon group having 1 to 6 carbon atoms A hydrogen group or an unsubstituted unsaturated hydrocarbon group, or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms, R ²
Is a substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or 3 to 6 carbon atoms.
Is an alicyclic saturated hydrocarbon group. ) Further, as the surface treatment agent capable of forming a hydrocarbon group layer on the surface of the semiconductor substrate and rendering the surface of the semiconductor substrate hydrophobic, it is preferable to use one containing a silane compound represented by the following general formula (23). it can.

R ² R ¹ _3-n Si (NR ³ ) _n (23) In the formula, n is an integer of 1 to ³ , R ³ is the same or different, and is a hydrogen atom or a carbon atom. R ¹ is an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms and R ¹ is the same or different and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, 1 carbon atom. ~ 6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C3
To 6 alicyclic saturated hydrocarbon groups, R ₂ has 3 carbon atoms
~ 6 substituted saturated hydrocarbon group or unsubstituted saturated hydrocarbon group, C3-6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C3-6 alicyclic saturated carbon group It is a hydrogen group.

As a first example of the silane compound represented by the general formula (23), a silane compound represented by the following general formula (24) can be used.

R ² R ¹ ₂ SiNR ³ ₂ (24) However, the meanings of R ¹ , R ² and R ³ are the same as in the general formula (23).

The silane compound represented by the general formula (24) has a single hydrolyzable group on the Si atom, the semiconductor substrate is processed into a monomolecular film, and the in-plane uniformity is high. A film is obtained. Further, the silane compound represented by the general formula (24) is easily affected by the steric hindrance of the R ¹ or R ² substituent, and this property is reflected in the reaction rate (processing ability).

As a second example of the silane compound represented by the general formula (23), a silane compound represented by the following general formula (25) can be used.

R ² R ¹ Si (NR ³ ₂ ) ₂ (25) However, the meanings of R ¹ , R ² and R ³ are the same as in the general formula (23).

The silane compound represented by the general formula (25) has two hydrolyzable groups on the Si atom, is processed into a laminated film on the semiconductor substrate, and has a high processing ability.

As a third example of the silane compound represented by the general formula (23), a silane compound represented by the following general formula (26) can be used.

R ² Si (NR ³ ₂ ) ₃ (26) However, regarding the meaning of R ² and R ³ , the above general formula (2
Same as 3).

The silane compound represented by the general formula (23) has three hydrolyzable groups on the Si atom and is processed into a laminated film on the semiconductor substrate. The reactive silane compound may be hydrolyzed by moisture in the air to form a gel, which may cause particle contamination depending on the treatment method.

Further, as the surface treatment agent capable of forming a hydrocarbon group layer on the surface of the semiconductor substrate and rendering the surface of the semiconductor substrate hydrophobic, one containing a silane compound represented by the following general formula (27) is used. be able to.

[0112] _{^{(R 2 R 1 2 Si)}} 2 NR 3 ...... (27) where, R ³ is a hydrogen atom or a non-substituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ¹ is same or different And a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsaturated unsaturated hydrocarbon group, or carbon Number 3
To 6 alicyclic saturated hydrocarbon groups, R ² has 3 carbon atoms
~ 6 substituted saturated hydrocarbon group or unsubstituted saturated hydrocarbon group, C3-6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C3-6 alicyclic saturated carbon group It is a hydrogen group. The silane compound represented by the general formula (27) has a single hydrolyzable group on the Si atom, and the semiconductor substrate is processed into a monomolecular film to obtain a film having high in-plane uniformity. To be Further, the silane compound represented by the general formula (27) is easily affected by the steric hindrance of the R ¹ or R ² substituent,
This property is reflected in the reaction rate (processing capacity).

Further, as the surface treatment agent capable of forming a hydrocarbon group layer on the surface of the semiconductor substrate and rendering the surface of the semiconductor substrate hydrophobic, one containing a silane compound represented by the following general formula (28) is used. be able to.

[0114]

Embedded image (In the formula, m is an integer of 2 to 6, R ³ is a hydrogen atom or an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ^3
1 is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or
It is an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms, and R ² is
Substituted saturated hydrocarbon group or unsubstituted hydrocarbon group having 3 to 6 carbon atoms, substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group having 3 to 6 carbon atoms, or alicyclic ring having 3 to 6 carbon atoms Formula is a saturated hydrocarbon group. The silane compound represented by the general formula (28) has two hydrolyzable groups on the Si atom, is processed into a laminated film on the semiconductor substrate, and has high processing ability. Further, as the silane compound represented by the general formula (28),
It is preferable that m is 3 or 4.

The above general formulas (19), (23) and (27)
Specific examples of the silane compounds represented by (28) and (28) include those represented by (Chemical Formula 11).

[0116]

Embedded image

An experiment similar to that of the third embodiment was conducted using the silane compound shown in (Chemical Formula 11).
As shown in FIG.

[0118]

[Table 5]

The silane compounds represented by the general formulas (24) and (27) are particularly stable in terms of materials, and the silane compound represented by the general formula (26) is particularly reactive. It has features.

(Fourth Embodiment) The fourth embodiment realizes the above-mentioned third invention.

A pattern forming method according to the fourth embodiment of the present invention will be described below with reference to FIGS. 9 and 10.

FIG. 9 shows the surface condition of the semiconductor substrate when the surface treatment with the surface treatment agent according to the fourth embodiment is performed, and FIG. 10 shows the surface treatment with the surface treatment agent according to the fourth embodiment. The schematic cross-sectional shape of the pattern formed on the semiconductor substrate is shown.

First, as shown in FIG. 9A, IP as a surface treatment agent is applied to the surface of the semiconductor substrate 1 made of silicon.
TMS is supplied (that is, IPTMS is bubbled with nitrogen gas and sprayed on the surface of the semiconductor substrate heated to 60 ° C. for 30 seconds) to make the surface of the semiconductor substrate 1 hydrophobic so that the semiconductor substrate 1 adheres closely. Improve sex. By doing so, as shown in FIG. 9B, H of the OH group on the surface of the semiconductor substrate 1 is replaced with Si (CH ₃ ) ₃ (trimethylsilyl group), and (CH ₃ ) ₂ CO (acetone) is obtained.
Is generated.

Next, after applying a resist on the surface of the semiconductor substrate 1, it is exposed using a desired mask, and then PE
B and development are sequentially performed to form a pattern.

When the pattern is formed as described above,
As shown in FIG. 10, a resist pattern 7 having a good shape with no peeling portion was formed on the semiconductor substrate 1. That is, in FIG. 10, a positive type resist (PFI-38 manufactured by Sumitomo Chemical Co., Ltd.) is applied on the semiconductor substrate 1 to a film thickness of 1.0 μm, and then exposed by an i-line stepper with NA: 0.6. , Then PEB is 90 at a temperature of 100 ° C.
The cross-sectional shape of a 0.30 μm line-and-space pattern is shown when the development is performed for 2 seconds and using a 2.38 wt% tetramethylammonium hydroxide aqueous solution.

As described above, according to the fourth embodiment,
Since IPTMS is used as the surface treatment agent, the adhesion with the semiconductor substrate 1 can be enhanced, and a good resist pattern shape without peeling can be obtained.

In the fourth embodiment, the semiconductor substrate 1
Since the adhesion between the resist pattern 7 and the resist pattern 7 depends on the hydrophobicity of the surface-treated semiconductor substrate 1, the type of the resist forming the resist pattern 7 is not limited, and the naphthoquinone diazide compound and the novolac resin are mainly used. The included resist and the chemically amplified resist described in the first to third embodiments can be widely used.

As the surface treatment agent for increasing the hydrophobicity of the semiconductor substrate and improving the adhesion between the resist and the substrate, those containing a silane compound represented by the following general formula (29) can be used.

R ¹ _4-n Si (OR ⁴ ) _n (29) In the formula, n is an integer of 1 to 3, and R ⁴ is a carbon number of 1 to 1.
A substituted saturated hydrocarbon group having 6 carbon atoms, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group having 1 to 6 carbon atoms or an unsubstituted alkylcarbonyl group, R ¹ is the same or different and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated group. A hydrocarbon group, or
It is an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms. ) As a first example of the silane compound represented by the general formula (29), a compound represented by the following general formula (30) can be mentioned.

R ¹ ₃ SiOR ⁴ (30) (However, for the meanings of R ¹ and R ⁴ , the above general formula (2
It is the same as 9). ) The silane compound represented by the general formula (30) has a single hydrolyzable group on the Si atom and is processed into a monomolecular film on the semiconductor substrate to form a film having high in-plane uniformity. can get. Further, the silane compound represented by the general formula (30) is easily affected by the steric hindrance of the R ¹ substituent, and this property is reflected in the reaction rate (processing ability).

As a second example of the silane compound represented by the general formula (29), a silane compound represented by the following general formula (31) can be used.

R ¹ ₂ Si (OR ⁴ ) ₂ (31) (However, for the meaning of R ¹ and R ⁴ , the above general formula (2
It is the same as 9). The silane compound represented by the general formula (31) has two hydrolyzable groups on the Si atom, is processed into a laminated film on the semiconductor substrate, and has high processing ability.

As a third example of the silane compound represented by the general formula (29), a silane compound represented by the following general formula (32) can be used.

R ¹ Si (OR ⁴ ) ₃ (32) (However, for the meaning of R ¹ and R ⁴ , the above general formula (2
It is the same as 9). ) The silane compound represented by the general formula (32) has three hydrolyzable groups on Si atoms, is processed into a laminated film on a semiconductor substrate, and has a high processing ability, but unreacted silane. The compound may be hydrolyzed by moisture in the air to form a gel, which causes particle contamination depending on the treatment method.

The above general formulas (30), (31) and (3)
Specific examples of the silane compound represented by 2) include those represented by (Chemical Formula 12).

[0136]

Embedded image

When the same experiment as in the fourth embodiment was conducted using the silane compound represented by the above general formula (29), good results were obtained as shown in (Table 6).

[0138]

[Table 6]

The silane compound represented by the general formula (30) is particularly stable in terms of material, and the silane compound represented by the general formula (3) is
The silane compound represented by 2) has a characteristic of being particularly highly reactive.

[0140]

According to the pattern forming method of the first aspect of the present invention, the surface of the semiconductor substrate is treated with the surface treatment agent containing the silane compound represented by the general formula (1). Since no alkali component is generated on the surface of the semiconductor substrate, the acid generated from the chemically amplified resist by exposure does not react with the alkali component.
Therefore, it is possible to obtain a stable resist pattern shape in which the hardly soluble layer is not formed on the surface.

Further, conventionally, during exposure from exposure to PEB, the acid generated in the chemically amplified resist by exposure generates an alkali component such as HMDS. However, according to the pattern forming method of the invention of claim 1, there is a problem in that the insolubilized layer is formed on the surface of the resist pattern. Since the alkali component does not exist on the surface of the amplified resist, the acid generated in the chemically amplified resist by exposure is not deactivated, and as a result, a stable resist pattern shape in which the surface hardly soluble layer is not formed can be obtained. it can.

The invention of claim 2 limits the chemically amplified resist to one having an acid generator and a resin which becomes alkali-soluble by the action of an acid, and the invention of claim 3 provides the chemically amplified resist. And an acid generator, an alkali-soluble resin, and a compound or resin that becomes alkali-soluble by the action of an acid, and the invention of claim 4 provides a chemically amplified resist containing an acid generator and an alkali-soluble resin. And a compound or resin that causes a cross-linking reaction by the action of an acid, a two-component chemically amplified positive resist, a three-component chemically amplified positive resist, and a three-component chemically amplified negative resist. It is possible to prevent acid deactivation when a resist is used.

According to the pattern forming method of the fifth aspect of the present invention, the surface of the semiconductor substrate is covered by the general formulas (2), (3),
Since the surface treatment is performed with the surface treatment agent containing the silane compound represented by (4) or (5), a hydrocarbon group is present between the atom having an unpaired electron present on the surface of the semiconductor substrate and the chemically amplified resist. Spacing by layers is formed, and also
The hydrophobicity of the surface of the semiconductor substrate is improved. From this,
The acid generated from the chemically amplified resist and the unpaired electrons on the surface of the semiconductor substrate become difficult to react, the deactivation of the acid generated from the chemically amplified resist is prevented, and the bottom of the resist pattern is formed. Can be prevented.

The invention of claim 6 limits the chemically amplified resist to one having an acid generator and a resin which becomes alkali-soluble by the action of an acid, and the invention of claim 7 provides the chemically amplified resist. And an acid generator, an alkali-soluble resin, and a compound or a resin that becomes alkali-soluble by the action of an acid, and the invention of claim 8 provides a chemically amplified resist containing an acid generator and an alkali-soluble resin. And a compound or resin that causes a cross-linking reaction by the action of an acid, a two-component chemically amplified positive resist, a three-component chemically amplified positive resist, and a three-component chemically amplified negative resist. It is possible to prevent acid deactivation when a resist is used.

According to the pattern forming method of the ninth aspect, the surface of the semiconductor substrate is surface-treated with the surface-treating agent containing the silane compound represented by the general formula (6). Halogen group of
An unsaturated bond, a carbonyl group, or the like dilutes the electron density on the Si atom and increases the acidity to increase the reactivity with the substrate, so that more silyl groups are attached to the surface of the semiconductor substrate. Therefore, since the hydrophobicity of the semiconductor substrate surface is improved, the adhesion between the semiconductor substrate and the resist pattern is improved.

According to the pattern forming method of the tenth aspect of the present invention, since the resist is limited to one having a naphthoquinonediazide compound and a novolac resin, a semiconductor substrate using a resist having a naphthoquinonediazide compound and a novolac resin is used. The adhesion between the resist pattern and the resist pattern is improved.

According to the surface treatment agent of the eleventh aspect of the present invention, since the alkaline component is not generated on the surface of the semiconductor substrate after the surface treatment, deactivation of the acid generated from the chemically amplified resist by exposure can be surely prevented. It is possible to realize an excellent resist pattern shape.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a process of a pattern forming method according to a first embodiment of the present invention.

FIG. 2 is a schematic view showing a surface state of a semiconductor substrate when IPTMS is supplied in the pattern forming method according to the first embodiment.

FIG. 3 is a schematic diagram showing a cross-sectional shape of a resist pattern formed by the pattern forming method according to the first embodiment.

FIG. 4 is a flowchart illustrating a process of a pattern forming method according to a second embodiment of the present invention.

FIG. 5 is a schematic view showing a surface state of a semiconductor substrate when ATMS is supplied in the pattern forming method according to the second embodiment.

FIG. 6 is a schematic diagram showing a cross-sectional shape of a resist pattern formed by the pattern forming method according to the second embodiment.

FIG. 7 is a schematic diagram showing a surface state of a semiconductor substrate when IPHDMS is supplied in a pattern forming method according to a third embodiment of the present invention.

FIG. 8 is a schematic view showing a cross-sectional shape of a resist pattern formed by the pattern forming method according to the third embodiment.

FIG. 9 is a schematic diagram showing a surface state of a semiconductor substrate when IPTMS is supplied in a pattern forming method according to a fourth embodiment of the present invention.

FIG. 10 is a schematic diagram showing a cross-sectional shape of a resist pattern formed by the pattern forming method according to the fourth embodiment.

FIG. 11A is a diagram illustrating a contact angle that is a measure of the hydrophobicity of the surface of the semiconductor substrate, and FIG.
It is a characteristic view which shows the relationship between the number of x in a formula, and a contact angle.

FIG. 12 is a flowchart illustrating a process of a pattern forming method according to a first conventional example.

FIG. 13 is a schematic view showing a surface state of a semiconductor substrate when HMDS is supplied in the pattern forming method according to the first conventional example.

FIG. 14 is a schematic diagram showing a cross-sectional shape of a resist pattern formed by a pattern forming method according to a first conventional example.

FIG. 15 is a schematic view showing a cross-sectional shape of a resist pattern formed by a pattern forming method according to a first conventional example.

FIG. 16 is a diagram showing a correlation between the environmental concentration of trimethylsilanol, which is a decomposition product of HMDS, and the environmental concentration of ammonia.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2 made of silicon 2 Resist pattern 3 Hardly soluble layer 4 Bottom part 5 Semiconductor substrate made of BPSG 6 Resist pattern 7 Resist pattern

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 1, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0101

[Correction method] Change

[Correction contents]

R ² R ¹ _3-n Si (NR ³ ₂ ) _n (23) wherein n is an integer of 1 to ³ and R ³ is the same or different and is a hydrogen atom or It is an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ¹ is the same or different and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, and carbon number. 1 to 6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or carbon number 3
To 6 alicyclic saturated hydrocarbon groups, R ₂ has 3 carbon atoms
~ 6 substituted saturated hydrocarbon group or unsubstituted saturated hydrocarbon group, C3-6 substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group, or C3-6 alicyclic saturated carbon group It is a hydrogen group.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akiko Katsuyama 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. Industrial Technology Research Institute Co., Ltd.

Claims (11)

[Claims] The surface of a semiconductor substrate is represented by the following general formula (1)
A first step of performing a surface treatment with a surface treatment agent containing a silane compound, and a second step of applying a chemically amplified resist to the surface of the surface-treated semiconductor substrate to form a resist film, A third step of forming a resist pattern by exposing the resist film using a mask having a desired pattern shape and then developing the resist film. R ¹ _4-n Si (OR) _n (1) (where n is an integer of 1 to 3, and R is a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group) , substituted unsaturated hydrocarbon group or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or a substituted alkyl group or unsubstituted alkyl group having 1 to 6 carbon atoms, R ¹ is same or different A hydrogen atom, a substituted or unsubstituted saturated hydrocarbon group having 1 to 6 carbon atoms, a substituted or unsubstituted unsaturated hydrocarbon group having 1 to 6 carbon atoms, or carbon It is an alicyclic saturated hydrocarbon group of Formulas 3 to 6.) 2. The pattern forming method according to claim 1, wherein the chemically amplified resist in the second step contains an acid generator and a resin which becomes alkali-soluble by the action of acid. 3. The chemically amplified resist in the second step contains an acid generator, an alkali-soluble resin, and a compound or resin which becomes alkali-soluble by the action of an acid. The method for forming a pattern according to. 4. The chemically amplified resist in the second step contains an acid generator, an alkali-soluble resin, and a compound or resin that causes a crosslinking reaction by the action of an acid. The method for forming a pattern according to. 5. A first step of surface-treating a surface of a semiconductor substrate with a surface-treating agent containing a silane compound represented by the following general formula (2), (3), (4) or (5): The second step of forming a resist film by applying a chemically amplified resist on the surface of the surface-treated semiconductor substrate, and exposing the resist film with a mask having a desired pattern shape, followed by development. And a third step of forming a resist pattern. R ² R ¹ _3-n Si (OR) _n (2) (In the formula, n is an integer of 1 to 3, and R is a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group. A hydrogen group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group or an unsubstituted alkylcarbonyl group having 1 to 6 carbon atoms, and R ¹ is the same type. Or a different type, a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or , A C 3-6 alicyclic saturated hydrocarbon group, R ² is a C 3-6 substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group, C 3-6 substituted unsaturated carbon group Hydrogen group or unsubstituted unsaturated hydrocarbon group, or C3-6 An alicyclic saturated hydrocarbon _{^{group.) R 2 R 1 3-}} n Si (NR 3 2) n ...... (3) ( where, n in the formula is an integer from 1 to 3, R ³ may be homologous Or a different type, a hydrogen atom or an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ¹ is the same or different type, a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms, or An unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms, R ² is A substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or an alicyclic ring having 3 to 6 carbon atoms The formula is a saturated hydrocarbon group.) (R ² R ¹ ₂ Si) ₂ NR ³ (4) (wherein R ³ is a hydrogen atom or a carbon atom). It is an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ¹ is the same or different, and is a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, and 1 carbon atom. To a substituted unsaturated hydrocarbon group or an unsubstituted unsaturated hydrocarbon group, or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms, and R ² is a substituted saturated hydrocarbon group having 3 to 6 carbon atoms. A group or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms.) Chemical 1] (However, in the formula, m is an integer of 2 to 6, R ³ is a hydrogen atom or an unsubstituted saturated hydrocarbon group having 1 to 3 carbon atoms, R ¹ is a hydrogen atom, and 1 to 6 carbon atoms. A substituted saturated hydrocarbon group or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or an alicyclic saturated hydrocarbon group having 3 to 6 carbon atoms And R ² is a substituted saturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 3 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or It is an alicyclic saturated hydrocarbon group of 3 to 6.) 6. The pattern forming method according to claim 5, wherein the chemically amplified resist in the second step contains an acid generator and a resin which becomes alkali-soluble by the action of acid. 7. The chemically amplified resist in the second step contains an acid generator, an alkali-soluble resin, and a compound or resin which becomes alkali-soluble by the action of an acid. The described pattern forming method. 8. The chemically amplified resist in the second step contains an acid generator, an alkali-soluble resin, and a compound or resin that causes a crosslinking reaction by the action of an acid. The method for forming a pattern according to. 9. The surface of a semiconductor substrate is represented by the following general formula (6):
A first step of performing a surface treatment with a surface treatment agent containing a silane compound represented by the following, a second step of applying a resist to the surface of the surface-treated semiconductor substrate to form a resist film, And exposing the resist to light using a mask having a desired pattern shape, and then developing the resist pattern to form a resist pattern. R ¹ _4-n Si (OR ⁴ ) _n (6) (wherein n is an integer of 1 to 3, R ⁴ is a substituted saturated hydrocarbon group having 1 to 6 carbon atoms, and 1 to 1 carbon atoms) A substituted unsaturated hydrocarbon group of 6 or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group or an unsubstituted alkylcarbonyl group having 1 to 6 carbon atoms, R ¹ is the same or different, Atom, substituted saturated hydrocarbon group having 1 to 6 carbon atoms or unsubstituted saturated hydrocarbon group, substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or unsubstituted unsaturated hydrocarbon group, or having 3 to 6 carbon atoms It is an alicyclic saturated hydrocarbon group.) 10. The resist in the second step is
The pattern forming method according to claim 9, comprising a naphthoquinonediazide compound and a novolac resin. 11. A surface treatment agent for treating the surface of a semiconductor substrate, comprising a silane compound represented by the following general formula (7). R ¹ _4-n Si (OR) _n (7) (wherein n is an integer of 1 to 3 and R is a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group) A substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or a substituted alkylcarbonyl group having 1 to 6 carbon atoms or an unsubstituted alkylcarbonyl group, and R ¹ is the same or different. And a hydrogen atom, a substituted saturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted saturated hydrocarbon group, a substituted unsaturated hydrocarbon group having 1 to 6 carbon atoms or an unsubstituted unsaturated hydrocarbon group, or carbon It is an alicyclic saturated hydrocarbon group of the number 3 to 6.)