JPS58114033A - Formation of pattern - Google Patents

Abstract

PURPOSE:To obtain wide development latitude, high sensitivity, and high resolution, and to enable development not depending on an org. solvent, by using a positive resist material contg. an alkali-soluble polymer compd. having acid components on the side chains, and as a cross-linking agent, an azide compd. for use in exposure to high energy radiation, such as electron beams. CONSTITUTION:A resist material layer formed on a base contains a polymer, such as a methacrylate-methacrylic acid copolymer represented by formula (I) and a photocrosslinking agent, a compd. having at least 2 azide groups, such as 4,4'-diazidochalkone of formula II. Said polymer is cross-linked by the ordinary method, and patternwise exposed to high energy radiation. The exposed parts are solubilized in water or an aq. alkaline developing soln. by decomposition of the main chain and the cross-linking chains, and the unexposed parts remains insoluble due to the cross-linked structure, and resistant to swelling, therefore, wide developing latitude, high sensitivity, and high resolution are obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a method of forming a glossy turn, and more specifically, the present invention relates to a method for forming a glossy turn, and more specifically, the present invention relates to a method of forming a glossy turn, and more specifically, a method for forming a glossy turn using a positive resist material, for example, by exposure to high-energy radiation such as an electron beam. Later, a method for forming high quality image-wise resist strips on a substrate will be described.
C. Can be used to advantage.

(2) Background of the Technology As a recent trend, in the field of semiconductor devices, efforts are being focused on the development of microfabrication technology on the order of submicrons in order to increase the degree of integration of VC. In order to achieve a controlled narrow path light with submicron dimensions, it is necessary to use, for example, ii1' electron beam,
It is also known that lightless devices that utilize energy radiation, such as 111, gamma fine, etc., are also known. In order to fully demonstrate the performance of the KI41 powerless device, a 4-type or negative-spraying renost material of the Yuzu type has been proposed. For example, acrylic resin-based positive resist materials have a high resolution suitable for submicron processing, and are used in this technical field for noodle-shaped paper. It is being

(3) Prior art and problems For example, polymethyl methacrylate, which is one of the conventionally used acrylic resin-based positive resist materials,
When electron beam exposure of about 5×1 O-sC/eIn2 or more is applied to it, the main chain of the polymer in the electron beam irradiated part is cut and the molecular weight of that part becomes one to two digits. #1, and this decrease in molecular weight indicates that the solubility of the irradiated area in a developer (usually an organic solvent such as methyl isobutyl ketone) is significantly greater than that of the unirradiated area. Therefore, only the irradiated portion can be selectively dissolved and removed using an appropriate developer.

However, since such conventional arm turn forming methods utilize differences in solubility due to differences in molecular weight, (1) if development is carried out for a long time, unirradiated areas also tend to dissolve (narrow development tolerance). Every time).

(11) In order to induce a significant difference in solubility, it is necessary to significantly reduce the molecular weight, and therefore a large amount of irradiation charge is required (low sensitivity). Furthermore, the solvent used as a developer causes N&@ of resist and mother turns, leading to a decrease in resolution, and also causes health problems for workers and pollution.

(4) Purpose of the Invention The purpose of the present invention is to provide an improved method for forming a pattern/volume turn which eliminates the above-mentioned drawbacks, i.e., has wide development latitude, high sensitivity, 1Illps image resolution, etc. It is an object of the present invention to provide a method for forming a large amount of turns using high-energy radiation and no light using a positive-type renost material that can be developed without using a bath agent.

(5) Structure of the Invention As a result of conducting research to achieve all of the above objectives, the present inventor has discovered that the conventionally used azide crosslinking temperature-di-type Renost material has an acid component in its side chain, and therefore has a molecular compound and attenuated We have discovered that combinations of compounds are extremely useful.
To explain it clearly, A? according to the present invention? Quantity turn formation method: When forming a Km-shaped resist/mother turn on a substrate, alkali-soluble #! ! A layer of a di-type di-st-absorbing material comprising a polymer compound having the above-mentioned components and an at-compound having two azide groups combined therewith is formed on a substrate, and the formed Renost@ material is formed. The polymer compound of the layer is made into a resin by a conventional method, and the image-shaped palm turn of the energy radiating edge is exposed to light, and the lightless area is treated with water or an alkaline developing solution to form an image-shaped resist pattern. The main character is to develop the image.

In Specification 1 of the present application, the term "high-energy radiation" includes various forms of radiation such as electron beams, x-rays, gamma rays, etc., as is generally understood in this field. Therefore, although the invention will be described below with reference to electron beam anomalies in objects, it should be understood that the TFC invention is also useful in the case of other forms of high energy radiation anomalies, such as X-edges. I want to be understood.

In developing the present invention, we selected a number of polymer compounds that can be used as well-known type 4 type resist materials, and which are alkali-soluble and which include d-cargenic acid, sulfonic acid, etc. Selecting and advantageously using such polymeric compounds in the side chains of the brewer's tubes may be advantageous. A particularly preferred polymer compound useful in the present invention is a methacrylate ester-acrylic acid copolymer represented by the following formula: CH.

C0ORC00H (wherein RiJ, C1-CI alkyl, e.g. CHs
, -C2H5lc, tt, , C3H8+ C4H
(e, etc., m699-50, and louse is 1-50), methacrylic acid ester methacrylic acid copolymer represented by the following formula; (R, m and n in the formula are each , 2 same as the above definition), others, specifically, MMA-MAA copolymer, t-Bu
It includes MA-MAA combination, n-BuMA-MAA, etc.

Particularly preferred examples of acid compounds having at least two at groups useful as photocrosslinkers in the present invention include 4,4'-diazide chalcone represented by the following formula: 2,6-no-diazide represented by the following formula: (4'-azidobenzylidene)cyclohexanone: 2,6-no(4'-azidobenzylidene)-4-methylcyclohexanone: benzylidene)-4-hydroxyclohexanone; and others. These photo-crosslinking agents are activated by the action of nitrene radicals generated by decomposition when the positive-type resist material of the present invention is heated at a predetermined temperature or irradiated with light such as ultraviolet rays. The polymer compound is cross-linked, thus forming an insolubilized network structure therein. These photocrosslinking agents have sufficient crosslinking effect t-
To achieve this, it is generally advantageous to use an amount of about 1 to 301 parts, based on the weight of the polymeric compound used at the same time. Of course, it is also possible to use the photocrosslinking agent in an amount outside the above range depending on the type of polymer compound used, the desired F5'r result, etc.

In the pattern forming method according to the present invention, first, a Rennost solution is prepared from a positive Rennost material containing the polymer compound and a photo-linking agent, and this is applied as a resist onto the substrate to be etched. . Preferred substrates for the hook that may be used herein include semiconductor substrates such as silicon quaver, chrome plated glass, and gold JIKt such as aluminum.

In this field to make resist solution t--*
The solvents used can be used advantageously. Preferred examples of useful solvents include methyl ethyl ketone, methyl isobutyl lactone, cyclohexanone, acetone, tetrahydrofuran, benzene, toluene, xylene, dimethylformamide, methyl rosol heptatate, and others. Depending on the kVC required, mixtures of these solvents may be used.

A commonly used coating method is used to apply the obtained resist solution to a substrate. Preferred coating methods include spin-coating and others.

After forming a resist group on a substrate, the polymer compound within the resist region is crosslinked by preheating at fM degrees of 100 to 200°C or by irradiating light such as ultraviolet light, thereby making it insolubilized. A mesh structure is formed there.

Subsequently, an image-like pattern of high-energy radiation is irradiated onto the resist film Km using a conventional exposure apparatus. In this way, when a pre-crosslinked resist is irradiated with radiation, the main chain of the polymer compound in the irradiated area (exposed area) is cleaved.
1 and the cleavage of the cross-bonds are accelerated and the irradiated area is solubilized, while the unirradiated area (undissolved light area) remains insolubilized.

According to the present invention, in the subsequent development step, 'a
A pattern is formed by developing with T-solubilized aqueous solution or alkaline developer to dissolve and remove the portion.

In the present invention, alkaline development 'f&, Fi' includes an alkaline water bath solution such as potassium hydroxide, sodium hydroxide, etc. Such an alkaline water bath solution has a higher concentration of 1! in consideration of shortening the viewing time, etc. j
Although L can be used, concentrations of 1 to 30 L are generally preferred. It is also possible to use other alkaline liquids, such as an organic amine compound commercially available from Sigley under the trade name MF312.

(6) Examples of the invention The invention will now be illustrated by the following examples.

Example 1: Methyl methacrylate-methacrylic acid copolymer represented by the following formula (weight average molecular weight M, = 20x10'): C00CH,C00H (in the formula, r m: 11, 8:2) synthesized by a conventional method. Next. This copolymer was dissolved in photo-crosslinked methyl cellosol heptatate Vc to obtain a resist solution. This solution was spin-coated with silicone powder so that the film thickness when dried was 1 .mu.m, and then prebaked at a temperature of 170.degree. C. for 30 minutes in a nitrogen atmosphere. The imaged noodles were then subjected to a 9't-coating using a 20 k@V electron beam and developed with a 5% aqueous potassium hydroxide solution. A sensitivity of 5xlO'C/no was obtained.

Example 2: A t-butyl methacrylate-methacrylic dense copolymer (copolymerization ratio 7:3 mol, M = 2.5 x 10) was synthesized by a calculation method. In this co-1 combination, 2 is added as a photocrosslinking agent.
．． 6-No(4'-azidobenzylidene)-4-methylcyclohexanone was added in an amount of 11%, and this mixture was further dissolved in methyl teratosolpurate to form an 8 weight-resist solution. . This solution t, 1
Film thickness at 1Lfk is 1 μm
Silibake was carried out for 30 minutes at a temperature of .degree. Next, imagewise exposure was performed using an electron beam (20 keVq),
And MF312/water mixture mgIft (mixing ratio -1:
1. ) C developed. A sensitivity of I x 10'C/cps2 was obtained.

(7) Effects of the Invention According to the present invention, the cross-linked structure tube can be maintained in the portion not irradiated with high-energy radiation, so that the above-mentioned drawbacks of the conventional method can be overcome. That is, since the unirradiated portion has a crosslinked structure, a wide development latitude,
For example, it is possible to achieve this by adopting a spray development method, using a highly concentrated developer, and the like. This is because the non-irradiated areas are strongly inseparable, so there is no need to worry about their dissolution by the developer. moreover,
In this regard, it is possible to suppress the swelling of unirradiated areas, so it is possible to improve the resolution minutely, and because a highly concentrated developer can be used, the development time can be reduced. It can be significantly shortened. That is, compared to conventional resists, it is possible to easily form a noreen with high sensitivity and high resolution. moreover,
According to the present invention, since the use of a developer consisting of an organic solvent is unnecessary, it is possible to avoid swelling of the resist/f-turn within Km, problems regarding the health of workers, and problems with pollution. .

patent applicant Fujitsu Limited Tauri application agent Patent attorney Akira Aomizu Patent attorney Kazuyuki Nishidate Patent attorney Uchida graduate Patent attorney Akira Yamaguchi

Claims (1)

[Claims] 1. To form an image resist pattern on A&. Alkaline TIJ bath property A layer of a positive resist material comprising a polymer compound having an acid component in its O1 side chain and an azide compound having at least two at groups combined therewith is formed in the above-mentioned 2! ! The high-molecular compound of the formed yc resist material layer is placed on the i-plate by a conventional method to form a gI-shaped pattern Vcj of high-energy radiation, and then an image-shaped rhenostopper fi-y' is formed. In order to do this, the /4 turn forming method is to develop the above-mentioned light area with water or an alkaline developing bath to make it t-% mold.