JPH04366958A - Radiation sensitive resin composition - Google Patents

Abstract

PURPOSE:To enhance sensitivity and to improve resistance to dry etching in an atmosphere of oxygen by incorporating polysiloxane and a cross-linking agent and an oxygen generating substance. CONSTITUTION:The radiation sensitive resin composition comprises as a binder the polysiloxane, preferably, poly(silsesquioxane), a polyfunctional silicon- containing compound having >=2C-0-Si bonds cleavable by the action of acid as the cross-linking agent, and the acid generating substance generating acid by the action of radiation, such as light, electron beams, X-rays, or ion beams. The terminal silanol SiOH or its alkyl ether SiOR<1> of the polysiloxane chain condenses as a low-molecular polyfunctional silicon compound to cross-links with each other and functions as a negative resist.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to a novel resin composition that can be used as a constituent material of resists used in the manufacture of semiconductor devices, etc., and that responds to radiation such as light, electron beams, X-rays, or ion beams. It is something.

0002

2. Description of the Related Art As LSIs become more highly integrated, submicron-order microfabrication techniques are becoming necessary. For this reason, for example, in the etching process in the LSI manufacturing process, a dry etching technique that allows high precision and fine processing is employed.

[0003] In the dry etching technique, the substrate to be processed is covered with a resist material, this is patterned using light or an electron beam, and the resulting pattern is used as a mask to expose the substrate through the mask using reactive gas plasma. This is a technique for etching parts. Therefore, the resist used in the dry etching technique is made of a material that has submicron order resolution and sufficient reactive gas plasma resistance.

However, as the level differences on the substrate to be processed become larger and larger as devices become more highly integrated, there is a tendency to use thicker resist layers in order to flatten these level differences and to maintain the resist mask until the end of substrate processing. be. Therefore, in the case of optical exposure, there are constraints due to the depth of focus of the exposure optical system, and in the case of EB exposure, there are constraints due to the scattering phenomenon of electrons within the resist. Etching substrates is becoming difficult. For this reason, various new resist processes are being considered, one of which is a two-layer resist process.

[0005] This consists of a thick polymer layer (usually polyimide or heat-cured photoresist) for planarizing the substrate steps, and a thin layer of O2-RIE-resistant photoresist or EB resist on top. This method uses a structure consisting of the following as an etching mask for the substrate. In this technology, high resolution is provided by the thin upper resist layer, while dry etching resistance during substrate processing is ensured by the lower layer. The upper layer resist used in this two-layer resist process is O2
-Silicon-containing polymers with higher RIE resistance than the underlying material are suitable, typical examples of which are conventionally known include photocurable silicone resins.

[0006] These are known to have a silicone resin as a binder mixed with a photocrosslinking agent or a photopolymerization initiator, and can be used as a negative resist. An example of such a material is the one disclosed in Japanese Patent Application Laid-Open No. 61-20030. A composition comprising a resin having double bonds such as poly(acryloyloxymethylphenylethylsilsesquioxane) and bisazide can be used as a highly sensitive UV resist under a nitrogen atmosphere.

Further, Japanese Patent Publication No. 60-49647 describes a system using polysilane as a photopolymerization initiator. It has been shown that a composition consisting of poly(organosiloxane) having double bonds and dodecamethylcyclohexasilane has good properties as an ultraviolet curable resin.

Further, an example of using an organic peroxide as a photopolymerization initiator is disclosed in JP-A-55-127023. According to this article, it is stated that when various organic peroxides such as peroxyesters are used together with poly(organosiloxane) having double bonds, a uniformly cured film can be obtained by UV irradiation. .

A completely different example that can be used for the upper resist in the two-layer resist process is disclosed in Japanese Patent Application Laid-open No. 61-144639.
There are some that are disclosed in the publication. This invention is an OFP
Poly(phenylsilsesquioxane) and cis-(1,3,5,7-tetrahydroxy)-1,3 are added to a general-purpose positive photoresist such as R-800 (manufactured by Tokyo Ohka).
, 5,7-tetraphenylcyclotetrasiloxane, and can be used as a two-layer positive photoresist that can be developed with alkali.

Furthermore, the use of binders other than poly(siloxane) is also being considered. Japanese Patent Publication No. 1983-198
According to Publication No. 151, it is described that if a novolac resin having a trialkylsilyl group is used together with a diazonaphthoquinone photosensitizer, a two-layer positive photoresist sensitive to visible light can be obtained.

[0011]

[Problems to be Solved by the Invention] However, when conventional photosensitive resin compositions are used in a two-layer resist process, there are the following problems.

[0012] In general, the photocuring reaction that proceeds through organic radicals is inhibited by oxygen.
As seen in the example of Publication No. 030, high sensitivity cannot be achieved unless exposure is performed in a nitrogen atmosphere. Therefore, even in the example of JP-A-55-127023, although the properties of the cured film were improved, there was a problem in that it took a long time to cure.

[0013] Also, in the example of Japanese Patent Publication No. 60-49647, according to the findings of the inventor of this application, it is difficult to achieve sufficiently high sensitivity due to the presence of oxygen, although it is not as strong as with bisazide. Met.

[0014] Furthermore, in the examples of JP-A-61-144639 and JP-A-61-198151, the silicon content in the added silicon compound or resin is low, so they do not exhibit sufficient O2 -RIE resistance. .

[0015] The present invention was made in view of the above points, and therefore, an object of the present invention is to provide high sensitivity and high O
2 - To provide a novel radiation-sensitive resin composition having RIE resistance.

[0016]

[Means and effects for solving the problems] In order to achieve this object, the radiation-sensitive resin composition of the present invention uses poly(siloxane), preferably poly(silsesquioxane) as a binder. It also contains a polyfunctional silicon-containing compound having at least two C-O-Si bonds that can be broken by the action of an acid as a crosslinking agent, and also contains a polyfunctional silicon-containing compound having at least two C-O-Si bonds that can be cleaved by the action of an acid. It is characterized by containing an acid-generating substance that decomposes and generates acid under the action of radiation. This composition functions as a negative resist for the reasons described below.

Siloxane bond S in poly(siloxane)
The terminal that is not i-O-Si is silanol SiOH
and silanol alkyl ether SiOR1. These bonds are more unstable than siloxane bonds, Si-O-Si, and are easily condensed in the presence of acid and converted into siloxane bonds, Si-O-Si. Therefore, if this occurs between polymer chains, the molecular weight increases and gelation occurs, thus functioning as a negative resist.

However, as can be understood from this, the sensitivity of this resist system increases as the amount of silanol or alkyl ether of silanol increases. This meaning of "a large amount" may refer to the presence of the same polymer molecule, or it may be added as a second component. If they are in the same polymer molecule, it is necessary to lower the molecular weight,
For example, even if it is desired to significantly increase the sensitivity, there is a limit to lowering the molecular weight of the polymer in view of the physical properties of the coating film, and it may not always be possible to sufficiently increase the sensitivity.

When the second component is used, it is preferably a low molecular weight polyfunctional silicon-containing compound having at least two C--O--Si bonds that can be cleaved by the action of an acid. In this case, for a binder polymer having a molecular weight that is satisfactory in terms of the physical properties of the coating film,
A considerable amount of the polyfunctional silicon-containing compound can be added. At this time, the polyfunctional silicon-containing compound functions as a highly efficient crosslinking agent. Therefore, it is considered that the above system can meet the requirements for high sensitivity.

Poly(silsesquioxane) used as a binder is a type of silicone resin and belongs to those having a high silicon content. Therefore, high O2-RIE resistance can be imparted to the radiation-sensitive resin composition. This poly(silsesquioxane) can generally be easily obtained by hydrolysis and polymerization of a hydrolyzable trifunctional silane such as phenyltrichlorosilane or a mixture of two or more thereof. This is represented by the following general formula (1) (however, R1 and R2 are an alkyl group, a cycloalkyl group, an alkenyl group, or an aryl group, and may be the same or different at any copolymerization ratio. ,R
3 is hydrogen, an alkyl group, or an aryl group. Also, n is a positive integer).

[0021]

[Chemical 2]

[0022] Weight average molecular weight is 500 to 100,000
, preferably 500 to 50,000. If it is outside this range, the coating film will be too soft, difficult to dissolve in solvents, or sufficient sensitivity will not be obtained.

Such poly(silsesquioxane) is disclosed in, for example, Japanese Patent Application No. 1983, filed by the applicant of this application.
It can be synthesized by the method disclosed in Japanese Patent Application No. 283128 (Japanese Patent Application No. 61-127638), the method disclosed in US Pat. No. 4,826,943, and the like. Also, some of them are commercially available and may be used.

Linear poly(siloxane) is the most common other silicone resin, and most of them are liquid at room temperature. Those suitable for the purpose of the present invention include poly(diphenylsiloxane) and poly(methylphenylsiloxane). The latter, which is a copolymer, is used because it becomes solid when the phenyl group content is 75% or more. It is suitable to use a weight average molecular weight of 500 to 100,000, preferably 500 to 50,000.

The second radiation-sensitive resin composition of the present invention
C-O- which can be cleaved by the action of acid, which is an essential component of
As the low molecular weight polyfunctional silicon-containing compound having at least two Si bonds, silane polyol R4
4-nSi(OH)n, such as phenylsilanetriol C6H5Si(OH)3, diphenylsilanediol (C6H5)2Si(OH)2, etc. can be used. Another example is 1,4-bis(
It may also be a material that does not have multiple hydroxyl groups on the same silicon, such as hydroxydimethylsilyl)benzene.

Furthermore, even if the hydroxyl group is masked, it can be used as long as it can be easily removed by the action of an acid. Examples of such materials include tetraphenoxysilane (C6 H5 O)4 Si, tetrat-butoxysilane (t-C4 H9 O)4 Si, and tetraacetoxysilane (CH3 CO2)4 Si. The amount of these low molecular weight polyfunctional silicon-containing compounds added is 1 to 100% based on the weight of the binder polymer.
Generally, good results are obtained when the amount is used in a range of 10% to 60%, more preferably in a range of 10% to 60%. If the amount is outside this range, the coating film may become brittle or the effect of increasing sensitivity by addition may not be sufficient.

The acid generating substance, which is the third component constituting the radiation-sensitive resin composition of the present invention, decomposes under the action of radiation and generates acid. The generated acid is silanol SiOH or silanol alkyl ether SiOR.
1 into a siloxane bond Si-O-Si,
That is, the condensation reaction is catalyzed under heating conditions. Therefore, by selectively irradiating the coating film with radiation and then heating it, only the irradiated areas can be selectively cured.

As such acid generating substances, many conventionally known substances can be used. The triarylsulfonium salt represented by the following formula (2) is described in J.
V. Crivello et al. (e.g. J.P.
olymer Sci. , Polymer Che
m. Ed. , 18, 2677 (1980)), and some of them are currently commercially available (for example, Midori Kagaku). In addition, Ar in formula (2) is an aryl group, and X is BF4
− , PF6 − , AsF6 − , SbF6 −
, ClO4 − , CF3 SO3 − and the like.

Ar3 S+ X−
...(2) Moreover, the diaryliodonium salt represented by the following formula (3) is also described in J. V. Crivel
(e.g. J. Polymer
Sci. , Polymer Chem. Ed. ,22
, 69 (1984)), and some of them are currently commercially available (for example, Midori Kagaku). Note that Ar in formula (3)
is an aryl group, and X is BF4, PF6, AsF
6 − , SbF6 − , ClO4 − , CF3
SO3- etc.

Ar2 I+ X−
...(3) Furthermore, for example, the following halogen-containing compounds can also be used.

・2,4,6-tris(trichloromethyl)-s-triazine・2-phenyl-4,6-bis(trichloromethyl)-
s-triazine 2-styryl-4,6-bis(trichloromethyl)-
s-triazine・2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine・2-(4-butoxystyryl)-4,6-bis(trichloromethyl)-s-triazine・2-(4-dimethylaminostyryl)-4,6-bis(trichloromethyl)-s-triazine/2-tribromomethylquinaldine/2,4-dichlorobenzotrichloride/1,4-bis(trichloromethyl) Benzene and sulfonic acid esters such as benzointosylate and N-tosyloxyphthalimide can also be used.

[0032] These acid generating substances are contained in an amount of 0.01 to 50%, preferably 0.05 to 50%, based on the weight of the binder polymer.
It is preferable to add it in an amount in the range of 30%. Outside this range, the sensitivity may be low or the coating film may become brittle.

A pattern may be formed using the radiation-sensitive resin composition of the present invention as follows.

Poly(phenylmethylsilsesquioxane) (copolymerization ratio 1:1, weight average molecular weight 1710, specific dispersion 1.56) and 20% 1,4-bis(hydroxydimethyl cylyl) benzene, also 8
A film prepared from a resist solution containing % of triphenylsulfonium trifluoromethanesulfonate was selectively irradiated with an electron beam at an accelerating voltage of 20 kV while changing the exposure dose, and then baked at 160° C. for 2 minutes. The film is then developed with 4-methyl-2-butanone (hereinafter referred to as MIBK) and rinsed with 2-propanol (hereinafter referred to as IPA).

Sensitivity and contrast were determined from a curve (so-called characteristic curve, an example of which is shown in FIG. 1) obtained by plotting the residual film thickness after development normalized by the initial film thickness against the logarithm of the exposure dose. However, 0.36μC/cm2,
It was 3.2.

[0036]

EXAMPLES Examples of the radiation-sensitive resin composition of the present invention will be described below. It should be noted that the numerical conditions such as the materials used, the amount of the materials used, the processing time, the temperature, and the film thickness described in the following description are merely preferred examples within the scope of the present invention. Therefore, it should be understood that the present invention is not limited only to these conditions.

Examples of chemicals used in the present invention First, before explaining the examples, examples of the binder polymer, polyfunctional silicon-containing compound, and acid generating substance used in the radiation-sensitive resin composition of the present invention are shown below. Shown below.

<Example of binder polymer> Commercial product example poly(phenylsilsesquioxane); Petrar
ch Systems Inc. Co., Ltd., PS194, weight average molecular weight Mw1200-1600.

・Poly(diphenylsiloxane);Pet
rarch Systems Inc. Made by PS0
80, weight average molecular weight Mw1000-1400.

Poly(methylphenylsilsesquioxane); manufactured by Shin-Etsu Chemical, weight average molecular weight Mw 1710.

Synthesis example of products not commercially available Synthesis example of poly(cyclohexylsilsesquioxane) Cyclohexyltrichlorosilane (Petrarch Syst
ems Inc. MIBK250m
1 and cooled to -40 to -30°C using a dry ice/acetonitrile cold bath. To this was added 27.9 ml of triethylamine over 5 minutes. After stirring for 10 minutes, 30 ml of water are added dropwise over 30 minutes. After the dropwise addition was completed, the mixture was stirred at -40 to -30°C for 1 hour, and then the cold bath was removed and the temperature was allowed to rise naturally to room temperature. The mixture is then heated and refluxed for 2 hours. After cooling, the organic layer is washed with water until the aqueous layer is neutral. When MIBK is distilled off from the organic layer under reduced pressure, an oily substance is obtained.
1 g was obtained, which solidified when left overnight. A product having a weight average molecular weight Mw of 1500 (Mw/Mn 1.07) is obtained.

Synthesis example of poly(allyl silsesquioxane) For example, patent application No. 28312/1989 filed by the applicant of this application.
8 (Japanese Patent Application No. 61-127638),
It is synthesized according to the method disclosed in US Pat. No. 4,826,943.

Allyltrichlorosilane (Shin-Etsu Chemical) 50
g in 360 ml of MIBK and cooled to -40 to -30°C using a dry ice/acetonitrile cold bath. To this was added 39.7 ml of triethylamine over 5 minutes. After stirring for 10 minutes, 43 ml of water was added dropwise over 30 minutes. After the dropwise addition was completed, the mixture was stirred at -40 to -30°C for 1 hour, and then the cold bath was removed and the temperature was allowed to rise naturally to room temperature. Then, the mixture is heated and refluxed for 1 hour. After cooling, the organic layer is washed with water until the aqueous layer is neutral. MIBK is distilled off from the organic layer under reduced pressure to obtain 40 g of an oil.

[0044] This was dissolved in 40 ml of MIBK and kept at 25°C in a water bath. After adding 4 g of triethylamine to this solution, it was stirred for 30 minutes. Dilute with 200 ml of MIBK and acidify the solution by adding 7 ml of 6M HCl. Add another 200 ml of MIBK and wash the organic layer with water until the aqueous layer is neutral. MIBK is distilled off from the organic layer under reduced pressure to obtain 35 g of an oil. MIBK3
0 ml of methanol solution containing 30 ml of water
Pour into 0 ml. The resulting solid was filtered off and dried under vacuum overnight, leaving 12 g of solid. A product having a weight average molecular weight Mw of 7040 (Mw/Mn 1.65) is obtained.

<Example of polyfunctional silicon-containing compound> Example of commercially available product: tetraphenoxysilane; manufactured by Shin-Etsu Chemical.

・Diphenylsilanediol; Petra
rch Systems Inc. Made.

1,4-bis(hydroxydimethylsilyl)benzene; manufactured by Shin-Etsu Chemical.

- Tetraacetoxysilane; manufactured by Shin-Etsu Chemical.

Synthesis example of a product that is not commercially available: Tetra t
Synthesis Example of -Butoxysilane 20 g of silicon tetrachloride was added to 500 ml of t-butanol, heated under reflux for 1 hour, and then t-butanol was distilled off under reduced pressure to obtain 26 g of solid. 9 in deuterated chloroform
In 0MHz 1H NMR, absorption of a single methyl group proton was observed at δ1.05.

<Examples of acid generating substances> Midori Kagaku, triphenylsphosnium trifluoromethanesulfonate, bis(4-t-butylphenyl)iodonium hexafluoroantimonate, benzoin p-toluenesulfonate, 2,4,6 −
Tris(trichloromethyl)-s-triazine manufactured by Tokyo Kagaku, 2-tribromomethylquinaldine, 1,4-bis(trichloromethyl)benzene Examples of the radiation-sensitive resin composition of the present invention <Example 1> Poly(
methylphenylsilsesquioxane) (Mw1710,
Mw/Mn1.56) 0.50g, tetraphenoxysilane 0.10g, triphenylsulfonium trifluoromethanesulfonate 40mg, methoxyethyl acetate 5
ml and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution.

[0051] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

The residual film thickness after development of the obtained sample was measured using Talystep (Rank Taylor Hobson), normalized by the initial film thickness, and this value was plotted against the logarithm of the exposure dose ( The sensitivity was determined from the so-called characteristic curve (characteristic curve) and was found to be 10 μC/cm2. Contrast was 2.5.

<Example 2> Poly(methylphenylsilsesquioxane) (copolymerization ratio 1:1, Mw 1710, Mw
/Mn1.56) 0.50g, diphenylsilanediol 0.10g, triphenylsulfonium trifluoromethanesulfonate 40mg and methoxyethyl acetate 5m
1 and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution.

[0054] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 8.0 μC/c.
It was m2. The contrast was 2.2.

<Example 3> Poly(methylphenylsilsesquioxane) (Mw1710, Mw/Mn1.56)
0.50 g, 1,4-bis(hydroxydimethylsilyl)benzene 0.10 g, and triphenylsulfonium trifluoromethanesulfonate 40 mg were dissolved in 5 ml of methoxyethyl acetate, and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution. shall be.

[0057] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 0.40 μC/
cm2. Contrast was 3.3.

<Example 4> Poly(methylphenylsilsesquioxane) (Mw1710, Mw/Mn1.56)
0.50 g, 1,4-bis(hydroxydimethylsilyl)benzene 0.10 g, and triphenylsulfonium trifluoromethanesulfonate 40 mg were dissolved in 5 ml of methoxyethyl acetate, and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution. shall be.

[0060] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 160° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 0.36 μC/
cm2. Contrast was 3.2. The characteristic curve of this Example 4 is shown in the figure.

<Example 5> Poly(methylphenylsilsesquioxane) (Mw 1710, Mw/Mn 1.56)
0.50 g, 1,4-bis(hydroxydimethylsilyl)benzene 0.15 g, and triphenylsulfonium trifluoromethanesulfonate 40 mg were dissolved in 5 ml of methoxyethyl acetate and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution. shall be.

[0063] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 0.30 μC/
cm2. Contrast was 3.1.

<Example 6> Poly(methylphenylsilsesquioxane) (Mw1710, Mw/Mn1.56)
0.50 g, 1,4-bis(hydroxydimethylsilyl)benzene 0.05 g, and triphenylsulfonium trifluoromethanesulfonate 40 mg were dissolved in 5 ml of methoxyethyl acetate and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution. shall be.

[0066] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 0.35 μC/
cm2. Contrast was 3.2.

<Example 7> Poly(methylphenylsilsesquioxane) (Mw1710, Mw/Mn1.56)
0.50 g, 1,4-bis(hydroxydimethylsilyl)benzene 0.01 g, and triphenylsulfonium trifluoromethanesulfonate 40 mg were dissolved in 5 ml of methoxyethyl acetate, and filtered through a membrane filter with 0.2 μm pores to obtain a resist solution. shall be.

[0069] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 3.0 μC/c.
It was m2. Contrast was 3.5.

<Example 8> Poly(cyclohexylsilsesquioxane) (Mw1500, Mw/Mn1.07)
0.50 g, diphenylsilanediol 0.10 g, and 40 mg of triphenylsulfonium trifluoromethanesulfonate were dissolved in 5 ml of methoxyethyl acetate.
Filter through a membrane filter with 2 μm pores to obtain a resist solution.

[0072] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 12 μC/cm.
It was 2. Contrast was 2.0.

<Example 9> Poly(cyclohexylsilsesquioxane) (Mw1500, Mw/Mn1.07)
0.50 g of diphenylsilanediol, 0.10 g of diphenylsilanediol, and 40 mg of benzoin p-toluenesulfonate were dissolved in 5 ml of methoxyethyl acetate and filtered through a membrane filter having 0.2 μm pores to obtain a resist solution.

[0075] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was heated with an electron beam (ELIONIX, ELS330) with an acceleration voltage of 20 kV.
0), draw an appropriate number of evaluation figures by changing the exposure amount. This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 11 μC/cm.
It was 2. Contrast was 2.0.

<Example 10> Poly(methylphenylsilsesquioxane) (Mw 1710, Mw/Mn 1.56
), 0.10 g of 1,4-bis(hydroxydimethylsilyl)benzene, and 40 mg of triphenylsulfonium trifluoromethanesulfonate were dissolved in 5 ml of methoxyethyl acetate, and filtered through a membrane filter with 0.2 μm pores to form a resist. Make a solution.

[0078] Spin coat this onto a silicon wafer,
Pre-bake on a hot plate at 80°C for 1 minute.
A 0.25 μm film is formed. This sample was exposed to deep UV light (Xe-Hg lamp, CM250 cold mirror through a quartz mask with a chrome pattern).
(using a device attached to a non-PLA501 contact analyzer). This exposed sample is subjected to post-exposure baking at 120° C. for 2 minutes on a hot plate. Then, it is developed with MIBK for 30 seconds and rinsed with IPA for 30 seconds.

A characteristic curve was prepared from the obtained sample in the same manner as in Example 1, and the sensitivity was determined to be 0.2 mJ/c.
It was m2. The contrast was 2.2.

In the embodiments described above, the exposure light sources were electron beams and deep ultraviolet rays, but the radiation-sensitive resin composition of the present invention can be used with other light sources such as X-rays, short wavelength excimer lasers, ion beams, etc. It also shows the same effect as the example.

Furthermore, in the above-mentioned examples, an example was explained in which the radiation-sensitive resin composition of the present invention was used as a constituent material of a resist for pattern formation, but the application of the present invention is not limited to resists only. do not have. For example, it can be used as a junction coating agent or buffer coating agent for protecting semiconductor devices.

[0082]

Effects of the Invention As detailed above, the general composition of the radiation-sensitive resin composition of the present invention includes poly(siloxane) as a binder, preferably poly(silsesquioxane), and acid as a crosslinking agent. C-O which can be cleaved by the action of
It consists of a polyfunctional silicon-containing compound having at least two -Si bonds, and an acid-generating substance that decomposes and generates acid under the action of radiation such as light, electron beams, X-rays, or ion beams.

As mentioned above, the reason why this composition functions as a negative resist is that the ends of the poly(siloxane) that are not siloxane bonded Si-O-Si are silanol S.
This is because the alkyl ether SiOR1 of iOH or silanol condenses with a low molecular weight polyfunctional silicon-containing compound to form a crosslink due to the catalytic action of an acid.

In patterning, the low molecular weight polyfunctional silicon-containing compound in the present composition plays a role in significantly accelerating crosslinking, and can be added in a considerable amount to the binder. In addition, only a trace amount of acid is needed to catalyze the condensation, and therefore the amount of radiation irradiated to the acid generator required to generate it may be extremely small. This system is therefore able to achieve high sensitivity.

Furthermore, since poly(siloxane) with a high silicon content is used as the binder polymer, and the additive is also a polyfunctional silicon-containing compound with a high silicon content, high O2 -RIE resistance can be achieved.

From the above, when used as an upper layer resist in a two-layer resist process, for example, good results can be obtained in terms of shortening exposure time and high-precision etching processing.

Therefore, it can be expected to be applied to the manufacture of highly integrated semiconductor devices.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a characteristic curve of the radiation-sensitive resin composition of Example 4 of the present invention.

Claims (12)

[Claims] 1. A radiation-sensitive resin composition comprising poly(siloxane), a crosslinking agent, and an acid-generating substance that generates acid upon radiation. 2. The radiation-sensitive resin composition according to claim 1, wherein the poly(siloxane) has the following general formula (1).
) A radiation-sensitive resin composition characterized by being a poly(silsesquioxane) represented by
2 is an alkyl group, a cycloalkyl group, an alkenyl group, or an aryl group, and they may be the same or different at an arbitrary copolymerization ratio. Further, R3 is hydrogen, an alkyl group, or an aryl group. Further, n is a positive integer. ). [Chemical formula 1] 3. The radiation-sensitive resin composition according to claim 1, wherein the poly(siloxane) is a poly(diphenylsiloxane) having a weight average molecular weight in the range of 500 to 100,000. resin composition. 4. The radiation-sensitive resin composition according to claim 1, wherein the poly(siloxane) is poly(dimethylphenylsiloxane) having a weight average molecular weight in the range of 500 to 100,000. Sensitive resin composition. 5. The radiation-sensitive resin composition according to claim 1, wherein the crosslinking agent is a polyfunctional silicon-containing compound having at least two C-O-Si bonds that can be cleaved by the action of an acid. and the amount added is the poly(
A radiation-sensitive resin composition characterized in that the amount is in the range of 1 to 100% based on the weight of siloxane. 6. The radiation-sensitive resin composition according to claim 1, wherein the crosslinking agent is a polyfunctional silicon-containing compound having at least two or more hydroxyl groups, and the amount added is equal to the amount of the poly(siloxane). 1-100% of the weight of
A radiation-sensitive resin composition characterized in that the composition is within the range of 7. The radiation-sensitive resin composition according to claim 1, wherein the acid generating substance is a sulfonium salt, and the amount added is 0 based on the weight of the poly(siloxane).
．． 01 to 50%. 8. The radiation-sensitive resin composition according to claim 1, wherein the acid generating substance is an iodonium salt, and the amount added is equal to the amount of the poly(siloxane).
A radiation-sensitive resin composition characterized in that the amount is 0.01 to 50% based on the weight of the radiation-sensitive resin composition. 9. The radiation-sensitive resin composition according to claim 1, wherein the acid generating substance is an aromatic compound having at least one trichloromethyl group, and the amount added is equal to or less than the weight of the poly(siloxane). 0.01~
50%.A radiation-sensitive resin composition. 10. The radiation-sensitive resin composition according to claim 1, wherein the acid generating substance is an aromatic compound having at least one tribromomethyl group, and the amount added is equal to or less than that of the poly(siloxane). 0.01 per weight
50%. 11. The radiation-sensitive resin composition according to claim 1, wherein the acid generating substance is benzoin p-toluenesulfonate, and the amount thereof added is 0.01 to 0.01 to the weight of the poly(siloxane). 50%.A radiation-sensitive resin composition. 12. The radiation-sensitive resin composition according to claim 1, wherein the acid generating substance is N-p-toluenesulfonyloxyphthalimide, and the amount added is 0 based on the weight of the poly(siloxane). .01 to 50% of the radiation-sensitive resin composition.