JP3393915B2 - Chemically amplified resist composition - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a chemically amplified resist composition suitable for deep ultraviolet (including excimer laser) lithography.

[0002]

2. Description of the Related Art In recent years, submicron pattern formation has been required as the degree of integration of integrated circuits increases. In particular, excimer laser lithography has attracted attention because it enables the production of 64 and 256M DRAMs. With such changes in the light source, in addition to various properties such as heat resistance, residual film rate, and profile, which have been required for conventional resists, the following new features are required. A) High sensitivity to the above light source. B) High resolution. In view of such circumstances, so-called chemically amplified resists utilizing an acid catalyst and a chemical amplification effect have been proposed. The action of this resist is to change the solubility of the exposed portion and the non-exposed portion in the developing solution by the reaction using the acid generated from the photo-acid generator as a catalyst upon irradiation with light. A mold resist is obtained.

On the other hand, in the conventional resist composition, coatability,
In order to improve chemical resistance and adhesiveness, for example, JP-A-59
Various surfactants have been used as described in -155836 and JP-A-60-208749. However, in the chemically amplified resist composition, the addition of such a surfactant causes a development residue (scum) and a bridge, and there is a problem that the performance such as resolution and depth of focus deteriorates. Further, the minute scum on the silicon wafer becomes an obstacle during dry etching.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art to provide heat resistance, residual film rate, profile,
Focal depth, excellent in various properties such as resolution and sensitivity, and provides a chemically amplified negative Katare resist composition excellent in coating properties and safety.

[0005]

The present invention SUMMARY OF] is seen containing an alkali-soluble resin, a crosslinking agent, N- hydroxy imide compound photoacid generator containing at least one sulfonic acid ester and a low degree of polymerization polysiloxanes, N-hydroxyimi
A sulfonic acid ester of a compound of the general formula (I)

[Chemical 3] (In the formula, R ¹ is an optionally substituted arylene or ar
Represents a xylene or alkenylene group, R ² is a substituted
Represents an optionally substituted alkyl or aryl group
You ) Is an ester represented by
50-95% by weight, crosslinking agent 1-30% by weight, photo-acid generator 1-20
The chemically amplified negative resist composition is characterized in that the content is 0.0001 to 1% by weight and the low polymerization degree polysiloxane is 0.0001 to 1% by weight .

The arylene group represented by R ¹ is a monocyclic or bicyclic group, preferably phenylene or naphthylene. Examples of preferred substituents on the arylene group include a halogen atom, a nitro group and an acetylamino group. Similarly, as the alkylene group, linear or branched ones can be mentioned, and those having 1 to 6 carbon atoms are preferable. Particularly preferred is ethylene or propylene group. Examples of preferable substituents on the alkylene group include a halogen atom, a lower alkoxy group, and a monocyclic aryl group. Similarly, examples of the alkenylene group include those having 2 to 6 carbon atoms, preferably vinylidene group and the like. A monocyclic aryl group etc. are mentioned as a preferable substituent of an alkenylene group.

Examples of the alkyl group represented by R ² include linear, branched or cyclic ones, preferably linear ones having 1 to 8 carbon atoms. A lower alkoxy group etc. are mentioned as a preferable substituent of an alkyl group. Similarly, the aryl group may be monocyclic or bicyclic, and preferably monocyclic. Suitable ester represented by the general formula (I) includes general formula (I
I)

[0008]

[Chemical 4]

(In the formula, R ¹ represents an optionally substituted arylene, alkylene or alkenylene group,
R ² 'represents an optionally substituted alkyl or aryl group. However, when R ² 'is an alkyl or aryl group having a substituent, the substituent is not halogen. ). N
Specific examples of the sulfonic acid ester of the hydroxyimide compound include:

[0010]

[Chemical 5]

[0011]

[Chemical 6]

And the like.

The ester represented by the general formula (I) can be obtained, for example, by GF Jaubert, Ber., 28 , 360 (1895), DE Ames.
Et al., J. Chem. Soc., 3518 (1955) or MA Stolberg.
Et al., J. Amer. Chem. Soc., 79 2615 (1957) and other general formulas (III).

[0014]

[Chemical 7]

A cyclic N-hydroxyimide compound represented by the formula: wherein R ¹ has the same meaning as described above,
A sulfonic acid chloride represented by the formula R ² —SO ₂ Cl (wherein R ² has the same meaning as described above) is added under basic conditions, for example, by L. Bauer et al., J. Org. Chem. ., 24 , 129
3 (1959) and the like.

The ester represented by the general formula (I) may be used alone or in combination of two or more kinds.

The molecular weight of the alkali-soluble resin is GPC.
The polystyrene-converted weight average molecular weight determined by the method is 1000.
To 10,000, preferably 1500 to 8000, and particularly preferably 2000 to 5000. As the alkali-soluble resin, vinylphenol resin, isopropenylphenol resin, copolymer of vinylphenol and styrene (the ratio of vinylphenol in the copolymer is preferably 50 mol% or more), isopropenylphenol and styrene Copolymer (ratio of isopropenylphenol in the copolymer is preferably 50 mol% or more), partially alkyl etherified vinyl phenol resin, partially hydrogenated vinyl phenol resin, partially hydrogen Added vinylphenol / styrene copolymer (the proportion of vinylphenol in the copolymer is 50 mol%
The above is preferable) and partially alkyl etherified hydrogenated vinylphenol resin and the like. These alkali-soluble resins may be used alone or in combination of two or more.

Examples of the crosslinking agent include Japanese Patent Application No. 4-15009.
And those containing a methylol group or a methylol ether group described in No. Preferably, for example

[0019]

[Chemical 8]

And the like. The cross-linking agent containing a methylol group or a methylol ether group may be used alone or in combination of two or more.

As the low-polymerization degree polysiloxane, for example, the following formula

[0022]

[Wherein, Z _{1 to} Z ₆ are each independently a hydrogen atom, a lower alkyl group, a lower alkoxy group, an epoxy group, a polyoxyethylene alkyl (POA) group, an amino group, a carboxyl group, a hydroxyl group or an aralkyl group. Alternatively, it represents an aryl group, and m and n represent arbitrary integers indicating that the sum thereof has a low degree of polymerization. ] The polysiloxane of various molecular weight shown by these (a mixture may be sufficient) is mentioned. Specific examples of the low-polymerization degree polysiloxane include dimethylpolysiloxane, methylhydrogenpolysiloxane, methylphenylpolysiloxane,
Examples include silicone oil and modified silicone oil.

The set that put the chemically amplified negative resist composition <br/> composition ratio of the alkali-soluble resin 50 to 95 wt%, crosslinking agent 1-30
% By weight, 1 to 20% by weight of a photoacid generator, and 0.0001 to 1% by weight of a low degree of polymerization polysiloxane . At the chemical amplified negative Katare Soo <br/> DOO composition, optionally, a sensitizer, and a dye, various additives which are conventional in the art, such as adhesion improving agent added Good.

[0025] Normally, the resist solution in the negative Katare resist composition the whole mixture, so that the proportion of 10 to 50% by weight,
It is prepared by mixing with a solvent. Examples of the solvent used in this case include ethyl cellosolve acetate, methyl cellosolve acetate, ethyl cellosolve, methyl cellosolve, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol dimethyl ether, Examples thereof include ethyl lactate, butyl acetate, ethyl pyruvate, 2-heptanone, cyclohexanone, methyl isobutyl ketone and xylene. The said solvent is used individually or in combination of 2 or more types.

[0026]

Negative Katare resist composition of the present invention exhibits heat resistance, film thickness retention, profile, not only is excellent in various properties such as depth of focus, sensitivity and resolution, excellent in coating properties and safety Therefore, it is possible to form a highly accurate fine resist pattern in lithography using a deep ultraviolet ray (including excimer laser) light source.

[0027]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to the examples. In the examples, the number of parts means part by weight unless otherwise specified.

Example 1 Copolymer of p-vinylphenol and styrene [Linker CST-70 manufactured by Maruzen Petrochemical; molar ratio = 7/3] 8.1
Part, hydrogenated poly (p-vinylphenol) [Maruzen Petrochemical Maruka Linker PHM-C] 5.4 parts, hexamethylol melamine hexamethyl ether (crosslinking agent) 1.0
Parts, silicon oil (Toray Silicon SH-8400) 0.04 parts and N-hydroxysuccinimide methanesulfonic acid ester (photo acid generator) 1.0 parts were dissolved in diethylene glycol dimethyl ether 48 parts. This solution has a pore size of 0.1 μ
m through a Teflon filter to prepare a resist solution. This was coated on a silicon wafer washed by a conventional method to a thickness of 0.7 μm using a spin coater. Then, the silicon wafer was prebaked on a hot plate at 100 ° C. for 1 minute. Next, the coating film after prebaking was passed through a chromium mask having a pattern, and a KrF excimer laser stepper (manufactured by Nikon Corporation, NS having an exposure wavelength of 248 nm) was used.
R-1755 EX8A NA = 0.45) was used for exposure. After the exposure, the wafer was heated on a hot plate at 105 ° C. for 1 minute to crosslink the exposed portion. This was developed with a 2.00 wt% aqueous solution of tetramethylammonium hydroxide to obtain a negative pattern. As a result of observing the formed pattern with an electron microscope, a 0.22 μm fine pattern was resolved with a good profile at an exposure dose of 24 mJ / cm ² (248 nm), and the bridge between the patterns and the non-exposed portion of the wafer were formed. There was no scum.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takehiro Kusumoto 3-1,98 Kasugade, Konohana-ku, Osaka City Sumitomo Chemical Co., Ltd. (72) Inventor Hiromi Ueki, 3-chome, Kasugade, Konohana-ku, Osaka No. 98 Sumitomo Chemical Co., Ltd. (56) Reference JP 6-92909 (JP, A) JP 5-341531 (JP, A) JP 3-206458 (JP, A) JP JP 4-366958 (JP, A) JP 5-210239 (JP, A) JP 6-43647 (JP, A) JP 6-214391 (JP, A) JP 7-295220 (JP, A) JP 61-166544 (JP, A) JP 59-155836 (JP, A) JP-A-5-507563 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) ) G03F 7/00-7/42

Claims (2)

(57) [Claims] 1. At least one of an alkali-soluble resin, a crosslinking agent, and a sulfonic acid ester of an N-hydroxyimide compound.
A photoacid generator and a low degree of polymerization polysiloxane <br/> seen containing containing species, esthetic acid N- hydroxy imide compound
Is represented by the general formula (I) : (In the formula, R ¹ is an optionally substituted arylene or ar
Represents a xylene or alkenylene group, R ² is a substituted
Represents an optionally substituted alkyl or aryl group
You ) Is an ester represented by
50-95% by weight, crosslinking agent 1-30% by weight, photo-acid generator 1-20
% , And 0.0001 to 1% by weight of a low degree of polymerization polysiloxane , a chemically amplified negative resist composition. 2. An ester represented by the general formula (I) is represented by the general formula (II): (In the formula, R ¹ represents an optionally substituted arylene, alkylene or alkenylene group, R ² ′ represents an optionally substituted alkyl or aryl group, and R ² ′ is an alkyl group having a substituent or The chemically amplified resist composition according to claim 1 , wherein the substituent is not halogen in the case of an aryl group.).