JPH0331845A - Positive type photosensitive material - Google Patents

Abstract

PURPOSE:To enhance resolution and sensitivity of the photosensitive material and to reduce tendency to cause development faults, such as scum, by incorporating a specified alkali-insoluble vinyl resin and a specified photoactive agent. CONSTITUTION:This photosensitive material contains the alkali-insoluble vinyl resin having a number average molecular weight of 500 - 30,000 prepared by copolymerizing 20 - 90wt.% t-butyl alpha,beta-ethylenically unsaturated carboxylate, preferably, such as t-butyl (meth)acrylate with 80 - 10wt.% other alpha,beta-ethylenically unsaturated carboxylate, such as alkyl (meth)acrylate, and the photoactive agent made of an arylonium salt, preferably, such as arylsulfonium salt represented by the formula in an amount of 0.1 - 20wt.% of the resin.

Description

[Detailed Description of the Invention] The present invention is based on positive type +5 friendly material f-1, and more specifically, it has a high degree of clarification or particularly excellent t'L, printing plate, photo printing plate, etc. M scale positive photosensitive material useful as a material Integrated circuits are used in This is because the lithography technology for forming integrated circuits (t = t) has improved dramatically, and as a result of the increase in the degree of integration of 44-product circuits, it has become possible to have many functions in one S-product circuit. This is because of this.

For forming the FA circuit 1F, a negative type photoresist I, which is made of cyclized polyisoprene and added with photo-crosslinking bisazide, is currently used. This tight photoresist takes advantage of the phenomenon that bisazide 1 is decomposed by light irradiation to produce nitrene, which cross-links the ring j-hiboriisolon, making it difficult to dissolve in organic solvents, but there is a limit to resolution. , it is difficult to use it to manufacture a highly integrated circuit with a mounting thickness of 2 μm in IY.

On the other hand, quinone diazide 1 resin in phenol novola 1 resin
A positive photoresist made by mixing alkali water; When this photoresist is irradiated with ultraviolet rays, the quinone diazide monoarsenic compound passes through getene and becomes carboxylic acid, so the solubility of the photoresist in alkaline water becomes extremely high and the photoresist quickly dissolves. It is said that it is possible to achieve high resolution with this photoresist.The reason why positive-type photoresists have higher resolvability than negative-type photoresists is that they change from lipophilic to hydrophilic before and after UV irradiation. By indicating an extremely large change (hi).

However, phenolic novolac resins generally exhibit high melting points, although the melting points vary considerably depending on the stigma. The high melting point means that the photoresist film made from this material is very hard and brittle, and also has poor adhesion to the substrate. When a mask is vacuum-adhered to a film, cracks occur, reducing the performance of the manufactured integrated circuit.

Furthermore, 0.1)"-dinitroaryl methyl ester of carboxylic acid was physically mixed into a base-compatible polymer such as methyl methacrylate-1/-methacrylic acid copolymer as a positive-type Photosys 1 material. Otsu no (Tokukai Aki
However, the conventionally proposed bond-shaped wood resists 1-material I are known from Immili-1F No. 44). A photoresist layer is formed by mixing a photoresist and a photoresist such as Q, +, 1-dinitroaryl methyl ester, which is photosensitive and reduces the solubility of the polymer in alkali. In this case, in the resist layer, an insoluble polymer containing, for example, one scoop of naphthoquinone diazide is formed in the polymer,
When exposed to light, the naphthoquinone diazide is photodecomposed and converted into an alkali-soluble substance, so the polymer is developed by taking advantage of its increased solubility in alkali. Therefore, if the base-soluble polymer and the naphthoquinone diazide conjugate are not mixed sufficiently uniformly, an insoluble polymer cannot be obtained homogeneously.
It contains a mixture of soluble and insoluble polymers, and although it can be said to have higher resolving power than negative-type photo resists, it does have the problem of non-printing areas called scum, which can easily cause defects. .

Problems to be Solved by the Invention Therefore, there is a need for a positive photosensitive material that is useful as printing plates and photoresist materials and has high resolution but is less likely to cause development defects such as scum. is the purpose of the present invention.

Means for Solving the Problems According to the present invention, the above-mentioned object is achieved by preparing monobutyl esters of α,β-ethylenically unsaturated carboxylic acids 21) to 91) by weight 9
゜ and other α,β-ethynic unsaturations (to Hikimono 8~
Number average molecular weight 51 obtained by copolymerization of l + '1 weight pa 6
, 'I If ~ 3, +) To the alkali-insoluble vinyl resin and the vinyl resin, f) a photoactivator selected from the group consisting of 1 to 20 aryl onium salts. This is achieved using a positive-working photosensitive material that ages.

The vinyl resin used in the present invention is α,β ethylenically unsaturated carboxylic acid t-butyl ester 2(;~9+:
19o (by weight) and other α,β-ethynic unsaturations 1
Higashi 8(1-1))゛). It is an alkali-insoluble vinyl resin with a number average molecular weight of 51:l +1 to 3 (+, l) obtained by copolymerization of monomers.

Examples of the t-butyl ester of α,β-ethylenically unsaturated carboxylic acid include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, maleic acid, fumaric acid,
Dicarboxylic acids such as citraconic acid, mesaconic acid, and itaconic acid; acid anhydrides such as maleic anhydride and itaconic anhydride; and dicarboxylic acid monoesters such as monoethyl maleate, monoethyl fumarate, and monoethyl itaconate. 1-butyl ester of ' can be mentioned.

In addition, other α, β, β-ethylene saturated substances used in the present invention (for example, methyl methacrylate-1
~, ethyl methacrylate, n-butyl methacrylate
Methacrylic acid alkyl esters such as t-, g-butyl methacrylate, methyl acufury 1, acfuric acid alkyl esters such as isopropyl acrylate, cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, and cyclic methacrylic acid Alkyl esters, acrylics such as cyclohexyl acrylate-1-52-methylcyclohexyl acrylate! f2 Cyclic alkyl esters, methacrylic acid alkyl esters such as phenyl methacrylate and benzyl methacrytate, and acrylic acid aryl esters such as phenyl acrylate and benzyl acrylate.

Dicarboxylic acid esters such as diethyl marinate, diethyl fumarate, and diethyl itaconate; Esters, styrene, α-methylstyrene, 0
-methylstyrene, m-methylstyrene, ρ-methylstyrene, vinyl-1-luene, F]-methyl-xystyrene, acrylonitrile, methacrylatelyl, salt (hibinyl, salt-1hynylidene, acrylamide, methacrylamide, Vinyl acetate, ethylene, ) ``alpha, β-ethylenically unsaturated carboxylic acid ester with vinyl alcohol 4'' and α,/'J-ethylenically unsaturated carboxylic acid with vinyl alcohol 4゛and other α. β. β-ethylene saturation 1
The former 21) ~ 1) Weight ++,; and Ryo KS
+. Copolymerization is carried out at 3% of f~10 weight o, but the number average molecular weight is 50ξl~3+), +1)+)
The type and amount of the other (1) β-ethitonic unsaturation must be selected so that the resulting polymer is alkali-insoluble within the range of It can be carried out by any method such as suspension, suspension, milk, etc. In the new year, we have developed an alkali-insoluble film-forming vinyl resin containing t-butyl ester groups. On the other hand, for a specific amount of constant telephone properties, that is, the weight of the vinyl resin, 1), 1 to 21) "°1," arylsulfonium salt, or aryl yo 1-2r'
A photoactive agent selected from the following salts is provided, more specifically such a photoactive agent is a chiarylsulfonium salt as described below.

Or aryliodonium salt Any one or more of these may be advantageously used.

Additionally, various photosensitizers can be used in combination with the photoactive agent to increase the absorption of a given wavelength (light) of the photoactive agent. Photosensitizers that can be used in the present invention include benzophenone, 2-chlorothioxanthone''
, anthrone, 9-ethyl-xyanthracene, anthracene, pyrene, perylene, phenothiazine, benzyl,
Preferred are acridine orange, hexoflavin, cetoflavin-T, anthraquinone, 9,10-diphenyleneanthracene, 9-fluorenone, and the like.

The positive photosensitive material of the present invention is a homogeneous mixture consisting of a vinyl resin, a photoactivator, FG, and optionally a photosensitizer.
Unlike conventional photosensitive materials in which insoluble IM resins are mixed with resins, vinyl resins are inherently alkali-insoluble and merely form a cyst layer due to their film-forming ability. 9. The resist I made of the photosensitive material of the present invention does not have any problems such as a decrease in the degree of conformation and the occurrence of scum in non-image areas due to the mixture of alkali-soluble and alkali-insoluble resins. In *, the photoactive agent is excited by exposure to actinic light such as ultraviolet rays, and the t-butyl ester group is decomposed into carboxyl group and isobutyne due to the photocationic catalyst.

This decomposition reaction (61 after exposure to return) to 15
1] By heat treatment in the temperature range of 1°C, the vinyl resin, which is originally alkali-insoluble, is converted into an alkali-soluble resin9 (1). It has a unique characteristic that provides a resist that is highly sensitive and is less likely to cause surface defects such as scum.

295 parts of Kagaraoka 1 1 flies were charged into a reaction vessel, 1)] The heat was raised to 0°C, 40 parts of t-butyl methacrylate, 34 parts of n-butyl acrylate, 26 parts of methyl methacrylate, and azobisisobutyro. A monomer solution in which 1 part of nitrile (1 part) was mixed and dissolved was added dropwise to the reaction vessel over 3 hours. After 30 minutes, an initiator solution of 5 parts of toluene and 5 parts of azobisisobutyronitrile was added. The mixture was reacted for 1 hour to obtain a resin solution A having t-butyl ester groups.

1 soul λI 295 parts of flies were charged into a reaction vessel, and the temperature was raised to 85°C. Bisisobutyronitrile 1
．． A monomer solution in which the remaining parts were mixed and dissolved was added dropwise to the reaction vessel over a period of 3 hours. Sieve for 30 minutes, and then add 5 parts of toluene and 5 parts of azobisisobutyronitrile (+, I:+5 parts).
The reaction was carried out for 1 hour with the addition of lf3 deletion, and a resin solution B having a t-butyl ester group was obtained.

Form 1: Charge 95 parts of Tornizi into a reaction vessel, and add 1 t)l)'C
41) parts of t-butyl acrylate, n
A monomer solution prepared by mixing and dissolving 1.34 parts of -butyl acrylate, 2b parts of methyl methacrylate, and 1.1 parts of azobisisobutyronitrile was added dropwise to the reaction vessel over 3 hours. After 3 minutes, an initiator solution containing 5 parts of toluene and 15 parts of azobisisobutyronitrile was added and reacted for 1 hour to obtain a resin solution C having t-butyl ester groups. .

After charging 95 parts of utolene into a reaction vessel and raising the temperature to IO+JC, 40 parts of t-butyl acrylate, 1.35 parts of n-butyl acrylate, and 1.15 parts of methyl methacrylate were added.
A seven-mer solution prepared by mixing and dissolving 10 parts of 2-hydroxyethyl methacrylate and 1.0 part of azobisisobutycin sea urchin was added dropwise to the reaction vessel over 3 hours. After 30 minutes, add 5 parts of toluene and 1 azobisisobutyronitrile.
), l) 5 parts of an initiator solution were added and reacted for 1 hour to obtain a resin solution having t-butyl ester groups.

After charging 95 parts of toluene into a reaction vessel and raising the temperature to 80°C, 1-30 parts of t-butyl acrylate and 1-30 parts of t-maleic acid were added.
-10 parts of butyl ester, lobethyl acrylate-1-3
A seven-mer solution prepared by mixing and dissolving 5 parts of methyl methacrylate, 25 parts of methyl methacrylate, and 1.0 part of azobisisobutyronitrile was added dropwise to the reaction vessel over 3 hours.

3 () separation, then add 5 parts of toluene, 1 heliyl azobisisobutylene (1, l:l 5 parts of initiator solution and 1
The reaction was carried out for a period of time to obtain a resin solution E having t-butyl ester groups.

LL Charge 95 parts of toluene into a reaction vessel, heat 1) part to 0°C, and add 10 parts of t-butyl acrylate, 1.60 parts of n-butyl acrylate, and methyl methacrylate. Le-1 30 copies,
A monomer solution in which 1.0 part of azobisisobutyronitrile was mixed and dissolved was added dropwise to the reaction vessel over a period of 3 hours. 3()
An initiator solution containing 5 parts of toluene, 1) and 0.5 parts of azobisisobutyronitrile was added to the mixture, and the mixture was reacted for 1 hour to obtain a resin solution F having t-butyl ester groups.

Add 95 parts of toluene to the reaction vessel, add 1 t, +
=<2, 92 parts of t-butyl acrylate,
A monomer solution prepared by mixing and dissolving 1 to 8 parts of 2-hydroxyethyl methacrylate and 1.1 parts of azobisisobutyronitrile was added dropwise to the reaction vessel over 3 hours. 3 After the juice, add 5 parts of I. luene and 0 azobisisobutyronitrile.
, 05 parts of an initiator solution were added thereto and reacted for 1 hour to obtain a resin solution G having t-butyl ester groups.

8. Pour 140 parts of toluene into a reaction vessel and heat to 70°C, then add 40 parts of t-butyl acrylate, 34 parts of n-butyl acrylate, 1.26 parts of methyl methacrylate, and azobisisobutyro. A monomer solution in which 0.8 part of nitrile was mixed and dissolved was added dropwise to the reaction vessel over 3 hours. 30
After a few minutes, an initiator solution containing 5 parts of toluene and 5 parts of azobisisobutyronitrile Q, 1) was added, and the mixture was reacted for 1 hour to obtain a resin solution H having t-butyl ester groups.

G P C for resins A-H obtained in Synthesis Examples 1 to 8
The results of molecular weight measurements are shown in Table 1.

(Left below) T B MA = t-butyl methacrylate TBA
=t-butyl acrylate 1.? vIPvlA =
Methyl methacrylate 1・n-BA=n-phthyl acrylate-1-2-E HMA=2-ethylhexyl methacrylate 2-HE~IA=2-hydroxyethyl methacrylate-
1. D T B M-maleic acid cy'-t-butylene ester Fubata Uriichi The resin solution A I +,'lg having the t-butyl ester group obtained in Synthesis Example 1 was added as a photoactivator. Add triphenylsulfonium hexafluoroarsenate, 4 g, acid and mix to obtain a photosensitive solution.

Place the filtered solution on an aluminum 14 plate and spin coat it at 31 rpm to form a 2-3 μm coating. After drying this film at 80°C for 1 hour, it was exposed to a reduction projection exposure device (g-line, NA=%3
In step 5), from 1.1) to 2,1:171 m was exposed through a reticle having a 1:1 line and space pattern in 0.1 μm increments.7 At the same time, exposure was performed from a 5 μm line and space pattern. Exposure j wheat, 13 degrees
After heat treatment at C for 5 minutes, it was treated with an aqueous solution of sodium chloride (1 mol 06 solution) for 60 seconds, washed with water for 30 seconds, and dried.

The resist pattern thus obtained was observed using a scanning electron microscope and the following evaluations were made.

The results are shown in Table-2.

Sensitivity was expressed as exposure energy that reproduces a 5.0 μm mask pattern.

The solution means the limit dissolving power at an exposure dose that reproduces a mask pattern of 2.1') am, and is expressed in the number of μm.

Modern defects (scum) in the non-image margin area were determined by observing the peripheral area of a single fine resist pattern using SEM.

A resist pattern was formed in the same manner as in Example 1, and the resist performance was evaluated. The prefectures are shown in Table 2.

Table 1 shows the resin solution and photoactivator obtained in Example 6 and 7.8.
A resist pattern was formed in the same manner as in Example 1 using a mixed pattern based on the layout of No. 2, and the resist performance was evaluated.

The results are shown in Table-2.

(Margin below) (Note 1) Scum evaluation was performed using the following basic criteria.

O not seen at all △ Slightly seen at the interface between the pattern and the substrate Shun,
A resist pattern is formed in the same manner as the actual PAl,
Resist performance was evaluated. The results are shown in Table-3.

(U1) to LL After adding and mixing the photosensitizer shown in Table 3 to a solution consisting of a resin solution having a butyl ester group and a photoactive agent, a resist pattern was formed in the same manner as in Example 1. was formed and the resist performance was evaluated. The results are shown in Table-3.

Ecresol Novola 1 resin (molecular weight = 1301) 0,
Meta 7・Rose ratio = 607'4) 10g to 0-Nafl
- 2.6 g of quinone diacid 5-sulfonic acid chloride ester was mixed with 21) g of ethyl cellosolve acetate (
A resist pattern was formed in the same manner as in Example 1, and the resist performance was evaluated. The results are shown in Table-3.

As can be seen from the above results, when the Bong-type photosensitive material of the present invention is used, fine patterns with high sensitivity, high snoring power, and no scum can be obtained.

(Margin below) C) 13

Claims (5)

[Claims] (1) Number average molecular weight obtained by copolymerization of 20 to 90% by weight of t-butyl ester of α,β-ethylenically unsaturated carboxylic acid and 80 to 10% by weight of other α,β-ethylenically unsaturated compounds, with a number average molecular weight of 500 to 30,000
and a photoactive agent selected from the group consisting of arylonium salts in an amount of 0.1 to 20% by weight based on the vinyl resin. (2) The positive-working photosensitive material according to claim 1, wherein the arylonium salt is a sulfonium salt. (3) The positive-working photosensitive material according to claim 1, wherein the arylonium salt is an iodonium salt. (4) The positive photosensitive material according to claim 1, which contains 0.01 to 10% by weight of a photosensitizer. (5) The positive-working photosensitive material according to claim 1, wherein the t-butyl ester of α,β-ethylenically unsaturated carboxylic acid is acrylic acid t-butyl ester and methacrylic acid t-butyl ester. sexual material.