JPH07134412A - Negative type radiation sensitive resist composition - Google Patents

Abstract

PURPOSE:To obtain a resist compsn. having high resolution and high sensitivity, capable of giving a resist pattern having a satisfactory profile shape and suitable for use in the production of a semiconductor device or in the working of a transparent electric conductive film for a liq. crystal display. CONSTITUTION:A resin compsn. consisting of an alkali-soluble resin and alkoxymethylated amino resin is blended with a triazine compd. represented by formula I or a combination of the triazine compd. with a triazine compd. represented by formula II to obtain the objective radiation sensitive resist compsn. In the formula I, each of R<1> and R<2> is 1-3C alkyl. In the formula II, Z is 4-alkoxy-phenyl, 4-alkoxynaphthyl, 2-(3,5-dialkoxyphenyl)ethenyl, 2-(2-furyl)- ethenyl, 2-(5-alkyl-2-furyl)ethenyl, 3,4-methylenedioxyphenyl or 2-(3,4- methylenedioxyphenyl) ethenyl.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel negative-type radiation-sensitive resist composition, more specifically, suitable for microfabrication in the field of electronic industry such as manufacturing of semiconductor devices and processing of transparent conductive films for liquid crystal displays. The present invention also relates to a negative-type radiation-sensitive resist composition having high resolution and high sensitivity and capable of providing a resist pattern having a good profile shape.

[0002]

2. Description of the Related Art In recent years, the progress of high density and high integration of semiconductor devices has been remarkably advanced, and the resolution in the fine processing technology has been required up to the submicron region. Also, with respect to the lithography technique which is the mainstream in the field of manufacturing semiconductor devices, fine processing of 0.5 μm or less is required, and in order to meet this, Deep UV, i.
Light sources emitting single wavelengths such as rays and g rays, excimer lasers, and KrF lasers (wavelength 248 nm) have begun to be used, and resists sensitive to electron rays and X rays are being developed.

Various studies using a trichloromethylated triazine compound as a photopolymerization initiator or a photoacid generator have been positively conducted in recent years with respect to such a negative resist composition compatible with radiation. A monomer having an unsaturated group (JP-A-54-74887),
Compounds capable of addition polymerization having at least one ethylenically unsaturated double bond (JP-A-54-151024), monomers which are polymerized by free radicals or acids (JP-A-60-105667), etc. A crosslinkable resin component such as a resist composition in combination with a polymerizable monomer component, a cresol novolac resin, an alkoxymethylated melamine resin (JP-A-2-146044), polyhydroxystyrene (JP-A-4-136858) A resist composition in combination with is proposed.

However, in these resist compositions, the cross-sectional shape of the resist pattern obtained from the resist composition tends to give rise to a bad profile shape, and high resolution cannot be obtained. In addition, Deep UV, i-ray, g
It has the drawback of not having practical sensitivity to radiation such as rays, excimer lasers, electron beams, and X-rays.The triazine compound, which has a relatively high sublimation property, sublimes during post-baking after development, and It adhered to the wall in a crystalline state and dropped on the surface of the substrate to be processed, which caused etching failure during etching, causing abnormal pattern formation.

As described above, the negative resist composition containing a trichloromethylated triazine compound as a photosensitizer used in the above-mentioned lithography technique utilizing various radiations, which can cope with fine processing of 0.5 μm or less, is described below. The reality is that nothing practical has been obtained yet.

Therefore, in the field of manufacturing semiconductor devices and liquid crystal display elements, etching defects do not occur, and the resolution and the profile shape of the resist pattern are excellent.
Moreover, development of a negative-type radiation-sensitive resist composition having high sensitivity to various radiations is strongly desired.

[0007]

In order to meet such a demand, the present invention is sensitive to various radiations, has a high resolution, is excellent in the profile shape of a resist pattern, and does not cause etching defects. The purpose of the present invention is to provide a negative-type radiation-sensitive resist composition having high sensitivity and capable of realizing good pattern formation.

[0008]

Means for Solving the Problems As a result of intensive studies to develop a negative radiation-sensitive resist composition suitable for fine processing, the present inventors have found that an alkali-soluble resin and an alkoxymethylated amino resin The resin component consisting of
It has been found that the object can be achieved by blending a specific triazine compound, and the present invention has been completed based on this finding.

That is, according to the present invention, (A) a resin component consisting of an alkali-soluble resin and an alkoxymethylated amino resin, (B) (a) a general formula (I)

[Chemical 3] (Wherein R ¹ and R ² are each an alkyl group having 1 to 3 carbon atoms, and they may be the same or different from each other), or a triazine compound of the component (a) (B) General formula (II)

[Chemical 4] [In the formula, Z is 4-alkoxyphenyl group, 4-alkoxynaphthyl group, 2- (3,5-dialkoxyphenyl)
Ethenyl group, 2- (2-furyl) ethenyl group, 2- (5
-Alkyl-2-furyl) ethenyl group, 3,4-methylenedioxyphenyl group or 2- (3,4-methylenedioxyphenyl) ethenyl group] in combination with a triazine compound The present invention provides a negative-type radiation-sensitive resist composition characterized by the above.

Examples of the alkali-soluble resin used in the composition of the present invention include novolac resins, acrylic resins, copolymers of styrene and acrylic acid, polymers and copolymers of hydroxystyrene, poly α-methyl vinyl phenol, etc. Of these, polyhydroxystyrene and novolac resins are preferred, and alkali-soluble novolac resins are most preferred. The alkali-soluble novolak resin is not particularly limited, and those conventionally used as film-forming substances in positive photoresist compositions, such as aromatic hydroxy compounds such as phenol, cresol, and xylenol, and aldehydes such as formaldehyde are used. Those condensed in the presence of an acidic catalyst are used. The alkali-soluble novolac resin has a weight average molecular weight of 2,000 to 20,000, preferably 3,000 to 1,500 with the low molecular weight region cut.
The range of 0 is preferable.

Alkali-soluble novolak resins preferably used in the present invention include, for example, phenol, m-cresol and p.
-Condensation reaction of a mixed phenolic compound containing at least one selected from cresol, 2,5-xylenol and 3,5-xylenol in predetermined proportions with formalin in the presence of an acid catalyst It can be manufactured. In the present invention, when considering improvement of the resist pattern profile, it is preferable to use 30% by weight or more of m-cresol.

On the other hand, the polyhydroxystyrene is not particularly limited and known ones can be used, but those having a weight average molecular weight of 3,000 to 50,000, preferably 5,000 to 30,000 are suitable.

In the composition of the present invention, the alkoxymethylated amino resin which is the other resin component of the component (A) is particularly an alkoxymethylated melamine resin or an alkoxymethylated urea resin, specifically a methoxymethylated melamine. Resin, ethoxymethylated melamine resin, propoxymethylated melamine resin, butoxymethylated melamine resin, methoxymethylated urea resin, ethoxymethylated urea resin, propoxymethylated urea resin, butoxymethylated urea resin, and the like. They may be used alone or in combination of two or more. These alkoxymethylated amino resins are prepared by, for example, reacting melamine or urea with formalin in a boiling aqueous solution under an acid catalyst to obtain a condensate, which is then converted into a lower alcohol such as methyl alcohol, ethyl alcohol, propyl alcohol, or butyl alcohol. It can be produced by etherifying with an alcohol and then cooling the reaction solution to take out the precipitated resin.

Among the alkoxymethylated amino resins, alkoxymethylated melamine resin is particularly preferable,
This alkoxymethylated melamine resin is obtained by etherifying a methylol group of a methylolated melamine obtained by a conventional method, and has an average of 2.5 or more, preferably 3.5 or more etherified methylol groups. Is preferred. Practically commercially available Nikarac Mx-
750, Nikarac Mx-706, Nikarac Mx-1
01, Nicarax Mx-032, Nicalax Mx-70
8, Nicalaque Mx-40, Nicalaque Mx-31, Nicalaque Ms-11, Nicalaque Mw-22, Nicalaque Mw-30 (above, Sanwa Chemical Co., Ltd.), etc. can be preferably used. These may be used alone or in combination of two or more.

Next, in the composition of the present invention, as the component (B), (a) the triazine compound represented by the general formula (I), or the triazine compound of the (a) component and (b)
A combination of a triazine compound represented by the general formula (II) is used.

Examples of the triazine compound represented by the general formula (I) as the component (a) include 2- [2- (3,3
4-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2-
[2- (3-Methoxy-4-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5
-Triazine, 2- [2- (3-methoxy-4-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-
Ethoxy-4-methoxyphenyl) ethenyl] -4,6
-Bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-diethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5
-Triazine, 2- [2- (3-ethoxy-4-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-
Propoxy-4-methoxyphenyl) ethenyl] -4,
6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-4-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl)-
1,3,5-triazine, 2- [2- (3,4-dipropoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine and the like can be mentioned. These triazine compounds may be used alone or in combination of two or more kinds.

On the other hand, examples of the triazine compound represented by the general formula (II) of the component (b) used in combination with the triazine compound of the component (a) as desired include 2- (4-methoxyphenyl). ) -4,6-
Bis (trichloromethyl) -1,3,5-triazine,
2- (4-ethoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-propoxyphenyl) -4,6-bis (trichloromethyl) -1,3 5-triazine, 2- (4-butoxyphenyl) -4,6-bis (trichloromethyl) -1,
3,5-triazine, 2- (4-methoxynaphthyl)-
4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-ethoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2-
(4-propoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-butoxynaphthyl) -4,6-bis (trichloromethyl)-
1,3,5-triazine, 2- (4-methoxy-6-carboxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxy-
6-hydroxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (2-
Furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (5-methyl-2-furyl) ethenyl] -4,6-bis (trichloromethyl)- 1,3,5-triazine, 2- [2- (5
-Ethyl-2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2
-(5-Propyl-2-furyl) ethenyl] -4,6-
Bis (trichloromethyl) -1,3,5-triazine,
2- [2- (3,5-dimethoxyphenyl) ethenyl)
-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-methoxy-5-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3 , 5-Triazine, 2- [2- (3-methoxy-5-propoxyphenyl) ethenyl] -4,6-
Bis (trichloromethyl) -1,3,5-triazine,
2- [2- (3-ethoxy-5-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,
3,5-triazine, 2- [2- (3,5-diethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-ethoxy -5-Propoxyphenyl) ethenyl] -4,6-
Bis (trichloromethyl) -1,3,5-triazine,
2- [2- (3-propoxy-5-methoxyphenyl)
Ethenyl] -4,6-bis (trichloromethyl) -1,
3,5-triazine, 2- [2- (3-propoxy-5
-Ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2-
(3,5-Dipropoxyphenyl) ethenyl] -4,6
-Bis (trichloromethyl) -1,3,5-triazine, 2- (3,4-methylenedioxyphenyl) -4,
6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-methylenedioxyphenyl)
Ethenyl] -4,6-bis (trichloromethyl) -1,
3,5-triazine and the like can be mentioned. These triazine compounds may be used alone or in combination of two or more.

Among the trichloromethylated triazine compounds as the component (b), particularly preferred is 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl)-
1,3,5-triazine, 2- [2- (5-methyl-2
-Furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (3,4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,3 , 5-triazine, which are (a)
It is used in combination with the triazine compound as a component in an arbitrary ratio.

As an advantageous combination of the component (a) and the component (b), 2- (4-alkoxyphenyl) -4,6-bis (trichloromethyl) is added to the component (1) (i).
A combination of -1,3,5-triazine, (2)
For component (a), 2- (3,4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,
A combination of 3,5-triazine, (3) (a)
2- [2- (5-alkyl-2-furyl)]
Ethenyl] -4,6-bis (trichloromethyl) -1,
A combination of 3,5-triazine, (4) (a)
2- [2- (5-alkyl-2-furyl)]
Ethenyl] -4,6-bis (trichloromethyl) -1,
3,5-Triazine and 2- (3,4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,
3-component in combination with 3,5-triazine, and 2- (3,4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1 for component (5) (a) , 3,5-Triazine and 2- (4-alkoxyphenyl) -4,6-bis (trichloromethyl)-
Mention may be made of three components in combination with 1,3,5-triazine. Among these combinations, those comprising three components of (4) and (5), especially three components of (4). The one consisting of is preferred. Further, the proportion of the component (a) is preferably 50% or more based on the total amount of the triazine compound, but the component (b) is 2- (3,4-methylenedioxyphenyl). -4,6
When -bis (trichloromethyl) -1,3,5-triazine is used, the component (a) and the total amount thereof may be 50% or more based on the total weight of the triazine compound.

Regarding the blending ratio of each of the above-mentioned components in the composition of the present invention, the weight ratio of the alkali-soluble resin (A) and the alkoxymethylated amino resin is 60:40 to 99: 1, preferably 75:25. It is desirable to use it in such a ratio that the ratio becomes to 98: 2. If the ratio of these resin components exceeds the above range, a high-performance resist composition cannot be obtained even if the component (B) is blended.

Further, the component (B), that is, the triazine compound composed of the triazine compound of the component (a) alone or the combination of the component (b) and the component (b) is the above-mentioned (A).
0.5 to 15% by weight, preferably 1 to 10% based on the components
It is compounded in the range of weight%. This blending amount is 0.5% by weight
If it is less than 15% by weight, the object of the present invention is not sufficiently achieved, and if it exceeds 15% by weight, the solubility of the resist in an alkaline aqueous solution is deteriorated and the developability is deteriorated, which is not preferable.

The composition of the present invention contains, if necessary, compatible additives such as an additional resin and a plasticizer for improving the performance of the resist film, etc., within a range not impairing the object of the present invention. Stabilizers, surfactants, coloring agents for making the developed image more visible, and conventional additives such as sensitizers and antihalation dyes for further enhancing the sensitizing effect be able to.

The composition of the present invention is advantageously used in the form of a solution by dissolving each of the above components in an organic solvent. Examples of such organic solvents include ketones such as acetone, methyl ethyl ketone, cyclohexanone, isobutyl methyl ketone, isoamyl methyl ketone, 1,1,1-trimethylacetone; ethylene glycol, propylene glycol, diethylene glycol, ethylene glycol monoacetate or diethylene glycol. Polyhydric alcohols such as monoacetate monomethyl ether, monoethyl ether, monopropyl ether, monoisopropyl ether, monobutyl ether or monophenyl ether and derivatives thereof; cyclic ethers such as dioxane; and methyl acetate, ethyl acetate, Esters such as butyl acetate, methyl lactate, ethyl lactate, methyl pyruvate, ethyl pyruvate, ethyl 3-ethoxypropionate It is possible. These may be used alone or in combination of two or more.

Next, a method for forming a fine pattern using the solution of the negative-type radiation-sensitive resist composition thus prepared will be described. First, the resist composition is formed on a substrate such as a silicon wafer. After applying a solution of a substance with a spinner or the like and drying it to form a radiation sensitive layer, g ray, i ray, deep UV, excimer laser, or X ray is selectively irradiated through a mask, or
After irradiating by scanning with an electron beam, heat treatment is applied, and then development is carried out using an organic alkaline aqueous solution of, for example, 2 to 10% by weight of tetramethylammonium hydroxide or choline to selectively expose the non-irradiated portion. A resist pattern that is dissolved and removed and has an excellent profile shape can be formed.

[0025]

INDUSTRIAL APPLICABILITY The negative-type radiation-sensitive resist composition of the present invention can form a resist pattern having excellent resolution and profile shape, and can prevent contamination of the inner wall of a processing chamber with a sublimated triazine compound during post-baking. Prevention,
Further, since it is possible to improve etching defects and pattern defects due to the deposits falling on the surface of the substrate to be processed and has high sensitivity to various radiations, it is particularly suitable for manufacturing semiconductor devices in which microfabrication is progressing. Used for.

[0026]

EXAMPLES The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto. The sublimation degree in each example was evaluated as follows.

Sublimation degree: The obtained wafer was heated at 160 ° C.
After baking for 90 seconds, it was observed whether or not crystals of the triazine compound were observed on the inner wall of the processing chamber, and the results are shown below. A: No crystals are observed even after baking 300 sheets. ◯: Crystals are observed after baking 200 to 299 sheets. Δ: Crystals are observed after baking 100 to 199 sheets. X: Crystals are observed after baking 50 to 99 sheets.

Example 1 70: 3 by weight ratio of m-cresol and p-cresol
25 g of a cresol novolac resin (weight average molecular weight 6000) obtained by mixing in a proportion of 0, adding formalin thereto and condensing by an ordinary method using an oxalic acid catalyst, and Nikalac Mw-30 which is an alkoxymethylated melamine resin.
3% by weight (made by Sanwa Chemical Co., Ltd.) based on the resin component
(0.75 g) was dissolved in 100 g of ethyl lactate, and the solution was added with 2- [2-
(3,4-Dimethoxyphenyl) ethenyl] -4,6-
Pore size 0.2μm with bis (trichloromethyl) -1,3,5-triazine added at a ratio of 3% by weight and dissolved
A resist solution was obtained by pressure filtration using the membrane filter of.

Then, the obtained resist solution was left in an atmosphere of hexamethyldisilazane for 7 minutes for spin coating on a 5-inch silicon wafer surface-treated at 4000 rpm for 20 seconds, and then on a hot plate at 90 ° C. A resist layer having a thickness of 1.0 μm was formed by drying for 90 seconds. Then, on the formed resist layer, a reduction projection exposure apparatus for g-line 1505G7E (manufactured by Nikon Corporation)
After selectively exposing the g-line to heat treatment at 110 ° C. for 90 seconds, and then dipping it in a 2.38 wt% tetramethylammonium hydroxide aqueous solution at 23 ° C. for about 1 minute, the g-line is not irradiated. After dissolving and removing the part,
This wafer was placed on a hot plate at 160 ° C. for 9 minutes.
The resist pattern was obtained by baking for 0 seconds. This resist pattern was a 0.50 μm resist pattern having a good profile shape that was cut vertically from the silicon wafer surface. Further, 300 wafers were processed by the same operation, but no precipitation of triazine compound crystals was observed on the inner wall of the processing chamber.

Examples 2 to 9 The mixing ratio of the alkoxymethylated amino resin was 5% by weight.
(1.25 g), except that the type and blending amount of the triazine compound were changed as shown in Table 1, the same operation as in Example 1 was performed, and the degree of sublimation and sensitivity during post-baking of each resist were performed. I asked. The results are shown in Table 1.

[0031]

[Table 1]

Comparative Examples 1 to 5 The mixing ratio of the alkoxymethylated amino resin was 5% by weight.
(1.25 g), and the same operation as in Example 1 was performed except that the type and blending amount of the triazine compound were changed as shown in Table 2 to determine the sublimation degree of each resist during post-baking. It was The results are shown in Table 2.

[0033]

[Table 2]

In Tables 1 and 2, T ₁ , T ₂ , T ₃ and T ₄ have the following meanings. T ₁ : 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine T ₂ : 2- [2- (5-methyl-2-furyl) ethenyl] -4 , 6-bis (trichloromethyl) -1,3,5
-Triazine T ₃ : 2- (3,4-methylenedioxyphenyl)-
4,6-bis (trichloromethyl) -1,3,5-triazine T ₄ : 2- [2- (3,4-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3
5-triazine

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hatsuko Tanaka, 150 Nakamaruko, Nakahara-ku, Kawasaki-shi, Kanagawa Tokyo Ohka Kogyo Co., Ltd. (72) Hisashi Nakayama 150, Nakamaruko, Nakahara-ku, Kawasaki, Kanagawa Prefecture Tokyo Oka Kogyo Co., Ltd.

Claims (3)

[Claims] 1. A resin component comprising (A) an alkali-soluble resin and an alkoxymethylated amino resin, and (B)
(A) General formula: (Wherein R ¹ and R ² are each an alkyl group having 1 to 3 carbon atoms, and they may be the same or different from each other), or a triazine compound of the component (a) (B) General formula: [In the formula, Z is 4-alkoxyphenyl group, 4-alkoxynaphthyl group, 2- (3,5-dialkoxyphenyl)
Ethenyl group, 2- (2-furyl) ethenyl group, 2- (5
-Alkyl-2-furyl) ethenyl group, 3,4-methylenedioxyphenyl group or 2- (3,4-methylenedioxyphenyl) ethenyl group] in combination with a triazine compound A negative-type radiation-sensitive resist composition characterized by the following: 2. The mixing ratio of the alkali-soluble resin and the alkoxymethylated amino resin in the component (A) is 6 by weight.
The negative radiation-sensitive resist composition according to claim 1, which is in the range of 0:40 to 99: 1. 3. The negative radiation-sensitive resist composition according to claim 1, wherein the blending amount of the component (B) with respect to the component (A) is in the range of 0.5 to 15% by weight.