JPH0934105A - Positive type photosensitive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive compsn. forming a film less liable to shrinkage by baking after exposure and the reduction of thickness at the time of development, giving a satisfactory pattern shape and having high sensitivity and high resolving power. SOLUTION: This photosensitive compsn. contains a specified amt. of a resin (a) insoluble in water but soluble in an aq. alkali soln., a specified amt. of a compd. (b) which generates an acid when irradiated with active light or radiation and a specified amt. of a low molecular acid-decomposable dissolution retarding compd. (c) whose solubility in an alakli developer is increased by the action of the acid. The compd. (c) has a specified structure, a mol.wt. of <=3,000 and a specified molar extinction coefft.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive photosensitive composition used in a process for producing semiconductors such as ICs, a circuit substrate for liquid crystals and thermal heads, and other photofabrication processes. .

[0002]

2. Description of the Related Art Positive photoresist compositions include:
In general, a composition containing an alkali-soluble resin and a naphthoquinonediazide compound as a photosensitive material is used. For example, as "novolac type phenolic resin / naphthoquinonediazide-substituted compound" in US Pat. No. 3,666,473, US Pat. No. 4,115,128 and US Pat. No. 4,173,470, etc.,
As the most typical composition, "Novolak resin composed of cresol-formaldehyde / trihydroxybenzophenone-1,2-naphthoquinonediazidesulfonic acid ester" is exemplified by Thompson "Introduction to Microlithography" (LFThompson "Intr
oduction to Microlithography ") (ACS Publishing, N
o. 2, 19, p112-121).

In such a positive photoresist, which basically consists of a novolac resin and a quinonediazide compound, the novolac resin provides high resistance to plasma etching, and the naphthoquinonediazide compound acts as a dissolution inhibitor. Then, naphthoquinonediazide has the property of losing its dissolution inhibiting ability by generating carboxylic acid upon irradiation with light, and increasing the alkali solubility of the novolak resin.

From this point of view, many positive type photoresists containing novolac resin and naphthoquinonediazide type photosensitive material have been developed and put to practical use from the viewpoint of 0.8 μm.
Sufficient results have been achieved in line width processing down to about 2 μm. However, the degree of integration of integrated circuits has been increasing more and more, and in the manufacture of semiconductor substrates such as VLSIs, processing of ultrafine patterns having a line width of half a micron or less has been required. In order to achieve the required resolution, the wavelength of an exposure apparatus used for photolithography is becoming shorter and shorter, and now far ultraviolet light and excimer laser light (XeCl, KrF, ArF, etc.) have been studied. ing.

When a conventional resist composed of a novolak and a naphthoquinonediazide compound is used for lithography pattern formation using deep ultraviolet light or excimer laser light,
Because of the strong absorption of novolak and naphthoquinonediazide in the far ultraviolet region, light hardly reaches the bottom of the resist, and only a low-sensitivity, tapered pattern can be obtained.

One of the means for solving such a problem is as follows.
It is a chemically amplified resist composition described in U.S. Pat. No. 4,491,628 and European Patent No. 249,139. The chemically amplified positive resist composition generates an acid in the exposed area by irradiation with radiation such as deep ultraviolet light, and the reaction using the acid as a catalyst dissolves the active radiation irradiated area and the non-irradiated area in the developing solution. This is a pattern forming material that changes the properties and forms a pattern on a substrate.

Examples of such a combination include a combination of a compound capable of generating an acid by photolysis with an acetal or an O, N-acetal compound (Japanese Patent Application Laid-Open No. 48-89003), a combination of an orthoester or an amide acetal compound ( JP-A-5120714), a combination with a polymer having an acetal or ketal group in the main chain (JP-A-53-1)
No. 33429), a combination with an enol ether compound (JP-A-55-12995), a combination with an N-acyliminocarbonate compound (JP-A-55-126236), a combination with a polymer having an orthoester group in the main chain. (JP-A-56-17345), a combination with a tertiary alkyl ester compound (JP-A-60-3625), and a combination with a silyl ester compound (JP-A-60-10247).
No.) and a combination with a silyl ether compound (Japanese Unexamined Patent Publication No.
0-37549, JP-A-60-112446) and the like. These have high photosensitivity because the quantum yield exceeds 1 in principle.

Similarly, a system which is stable at room temperature over time but decomposes by heating in the presence of an acid to solubilize with an alkali is disclosed in, for example, JP-A-59-45439 and JP-A-60-3625. JP-A-62-229242, JP-A-63-27829, JP-A-63-36240, JP-A-63-250642, Polym.Eng.Sce., 23, 101
2 (1983); ACS.Sym. 242, 11 (1984); Semicond
uctor World 1987, November, p. 91; Macromolecules, 2
Vol. 1, p. 1475 (1988); SPIE, vol. 920, p. 42 (1988);
Combination systems with esters or carbonate compounds of primary or secondary carbons (eg t-butyl, 2-cyclohexenyl). These systems also have high sensitivity and have a deep-UV compared to the naphthoquinonediazide / novolak resin system.
Since the absorption in the region is small, it can be an effective system for shortening the wavelength of the light source.

The above-mentioned positive chemically amplified resist is a three-component composition comprising an alkali-soluble resin, a compound (photoacid generator) which generates an acid upon exposure to radiation, and a dissolution inhibiting compound for the alkali-soluble resin having an acid-decomposable group. The system can be roughly classified into a two-component system comprising a resin having a group which is decomposed by a reaction with an acid to be alkali-soluble and a photo-acid generator. In the case of a two-component system, the content of acid-decomposable groups in the resin increases, so there is a problem that the resist film shrinks due to baking after exposure.

On the other hand, the three-component system has a problem that the film is largely reduced at the time of development due to the insufficient dissolution inhibiting property with respect to the alkali-soluble resin and the resist profile is remarkably deteriorated. However, the three-component system is a promising system because of a wide range of choices of materials, and the development of an acid-decomposable compound having excellent dissolution inhibiting properties used in this system has been desired.

As such an acid decomposable compound, in the case of the compound described in JP-A-6-51519, that is, the compound in which the distance between the acid decomposable groups in the compound is a certain value or more,
It has been found to exhibit good dissolution inhibiting properties. However, it has been found that even in the case of these compounds, if the content in the composition is increased in order to obtain a sufficient dissolution inhibiting property, there is a new problem of forming a tapered pattern with low sensitivity.

[0012]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a positive-type photosensitive material which shows a good pattern shape with little film shrinkage due to baking after exposure and film loss during development, and which has high sensitivity and high resolution. To provide a sex composition.

[0013]

Means for Solving the Problems The inventors of the present invention have made intensive studies while paying attention to the above-mentioned characteristics. As a result, the object of the present invention is to provide an alkali-soluble resin, a photoacid generator, and a dissolution inhibitor having an acid-decomposable group. In a positive chemical amplification system comprising a compound, the present invention has been found to be achieved by using a low-molecular acid-decomposable dissolution inhibiting compound satisfying the following requirements as a dissolution inhibiting compound, and has reached the present invention.

That is, the present invention provides (a) a resin 50 to 8 which is insoluble in water and soluble in an aqueous alkali solution.
9.5% by weight, (b) 0.5 to 10% by weight of a compound capable of generating an acid upon irradiation with actinic rays or radiation, and (c) at least one selected from the following (i) and (ii)
10 to 45% by weight of a low molecular weight acid-decomposable dissolution-inhibiting compound having a molecular weight of 3000 or less, which has a structure of a species and whose solubility in an alkali developing solution is increased by the action of an acid, and (i) is a group decomposable by an acid. A structure (ii) having at least two and having at least 10 bond atoms excluding the acid-decomposable group at the farthest position between the acid-decomposable groups (ii) at least three groups decomposable by an acid A positive photosensitive composition having a structure in which the distance between the acid-decomposable groups is at the farthest position and the number of bonding atoms excluding the acid-decomposable group is 9 or more. The positive photosensitive composition is characterized in that the dissolution inhibiting compound (c) has a molar absorption coefficient ε at 248 nm of 3,000 or less.

The present inventors have found that when the molar extinction coefficient ε of the acid-decomposable dissolution inhibiting compound at 248 nm is high, a tapered pattern is formed, and each component is contained in a specific amount, It was also found that by using an acid-decomposable dissolution inhibiting compound having a specific molar extinction coefficient, a positive photosensitive composition having high sensitivity and high resolution without forming a tapered pattern can be obtained. .

The compounds used in the present invention will be described in detail below.

(A) Acid-decomposable dissolution inhibiting compound (Compound of the invention (c)) The acid-decomposable dissolution inhibiting compound used in the invention (c) is
Having at least two groups capable of being decomposed by an acid in its structure,
At the position where the distance between the acid-decomposable groups is farthest away, a compound or a compound which passes through at least 10, preferably at least 11, and more preferably at least 12 bond atoms excluding the acid-decomposable group. Have at least three,
A compound having at least 9, more preferably at least 10 and more preferably at least 11 bonding atoms excluding the acid-decomposable group at the position farthest from the acid-decomposable group, and at 248 nm The molar extinction coefficient ε is 3000 or less, preferably 2000 or less. Here, ε represents a value in a tetrahydrofuran solution.

Further, the preferable upper limit of the number of bonding atoms is 50.
The number is more preferably 30. The content of the compound of the present invention (c) in the composition is 10 to 45% by weight, preferably 15 to 45% by weight, more preferably 20 to 40% by weight.
If the amount is less than 10% by weight, the dissolution inhibiting property with respect to the alkali-soluble resin is lowered, and the developing film is reduced even in the unexposed portion during development. If it is more than 45% by weight, the compatibility with other compositions is deteriorated and the film formability of the resist film is deteriorated.
Further, as a result, the content of acid-decomposable groups increases, and the resist film contracts significantly when baked after exposure.

In the present invention, when the acid-decomposable dissolution inhibiting compound has three or more acid-decomposable groups, preferably four or more, even if it has two acid-decomposable groups, the acid-decomposable group is also preferable. Are more than a certain distance apart from each other,
The dissolution inhibiting property with respect to the alkali-soluble resin is significantly improved. When the molar extinction coefficient ε at 248 nm of the acid-decomposable dissolution-inhibiting compound is 3000 or less, preferably 2000 or less, it does not show a tapered shape in the range of the content in the composition of the present invention, and has a rectangular shape. Form a pattern profile.

The distance between acid-decomposable groups in the present invention is represented by the number of via-bonded atoms excluding acid-decomposable groups. For example, in the case of the following compounds (1) and (2), the distance between the acid-decomposable groups is 4 bonding atoms, and in the compound (3), the bonding atom is 12 bonding atoms.

[0021]

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The acid-decomposable dissolution inhibiting compound of the present invention may have a plurality of acid-decomposable groups on one benzene ring, but preferably one benzene ring has one acid-decomposable group. It is a compound composed of a skeleton having an acid-decomposable group. Further, the molecular weight of the acid-decomposable dissolution-inhibiting compound of the present invention is 3,000 or less, preferably 500 to 3,000.
0, more preferably 1,000 to 2,500.

In a preferred embodiment of the present invention, the group containing an acid-decomposable group --COO--A ⁰ ,-O--B ⁰ is --R ⁰ --COO--A ⁰ or --Ar--O. -B
^And a group represented by ⁰ . Where A ⁰ is −C
( ^R01 ) ( ^R02 ) ( ^R03 ), -Si ( ^R01 ) ( ^R02 )
(R ^{0 3} ) or —C (R ⁰⁴ ) (R ⁰⁵ ) —O—R ⁰⁶ group is shown. B ⁰ represents A ⁰ or a —CO—OA ⁰ group.

R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R ^{05, which} may be the same or different, each represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group or an aryl group, and R ⁰⁶ is An alkyl group or an aryl group is shown. However, at least two of R ^{01 to} R ⁰³ are groups other than a hydrogen atom, and two groups of R ^{01 to} R ⁰³ and R ^{04 to} R ⁰⁶ are bonded to form a ring. Is also good. R ⁰ represents a divalent or higher valent aliphatic or aromatic hydrocarbon group which may have a substituent, and -Ar- is a divalent or higher valent which may have a monocyclic or polycyclic substituent. Shows an aromatic group.

Here, the alkyl group is preferably one having 1 to 4 carbon atoms such as methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, t-butyl group, and cycloalkyl group. Preferred are those having 3 to 10 carbon atoms such as cyclopropyl group, cyclopentyl group, cyclohexyl group and adamantyl group, and the alkenyl groups are those having 2 to 2 carbon atoms such as vinyl group, propenyl group, allyl group and butenyl group. Four aryl groups are preferable, and the aryl group has 6 to 1 carbon atoms such as phenyl group, xylyl group, toluyl group, cumenyl group, naphthyl group and anthracenyl group.
Four are preferred.

As the substituent, a hydroxyl group, a halogen atom (fluorine, chlorine, bromine, iodine), a nitro group, a cyano group, the above alkyl group, a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, a hydroxypropoxy group. Group, n-butoxy group, isobutoxy group, sec-butoxy group, t-butoxy group, and other alkoxy groups, methoxycarbonyl group, ethoxycarbonyl group, and other alkoxycarbonyl groups, benzyl group, phenethyl group, cumyl group, and other aralkyl groups, Acryl groups such as aralkyloxy groups, formyl groups, acetyl groups, butyryl groups, benzoyl groups, cyanayl groups, valeryl groups, acyloxy groups such as butyryloxy groups, the above alkenyl groups, vinyloxy groups, propenyloxy groups, allyloxy groups, butenyloxy groups. Alkenyloxy groups such as Serial aryl group, an aryloxy group such as phenoxy group, and an aryloxycarbonyl group such as benzoyloxy group.

Preferably, silyl ether group, cumyl ester group, acetal group, tetrahydropyranyl ether group, enol ether group, enol ester group, third group
And a tertiary alkyl ester group and a tertiary alkyl carbonate group. More preferably, tertiary alkyl ester groups such as t-butyl ester groups, tertiary alkyl carbonate groups such as t-butyl carbonate groups, aralkyl ester groups such as cumyl ester groups, tetrahydropyranyl ether groups, methoxymethyl ether groups. , 1-ethoxy-1-ethyl ether group, 1-t-butoxy-1-ethyl ether group, 2-methoxy-2-propyl ether group and the like.

In the present invention, preferably the following (a) to
(C) A part or all of the phenolic OH groups of a polyhydroxy compound having at least one structural feature of any of the above is bound by the above-described group —R ⁰ —COO—A ⁰ or B ⁰ group. , A protected compound. (A) A structure in which a benzene ring is bonded via an alkylene chain having two or more carbons, (b) a structure without a methine moiety in which three benzene rings are bonded on the same carbon, and (c) on a benzene ring. A structure in which an alkyl or cycloalkyl group having 4 or more carbon atoms is substituted.

Among these structures, particularly those having the structure (c), and those having the structure (c) in which a cycloalkyl group having 4 or more carbon atoms is substituted on the benzene ring are applied. In some cases, favorable results are obtained.

Specific examples of the acid-decomposable dissolution inhibiting compound of the present invention include compounds represented by the general formulas [I] to [X].

[0031]

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[0032]

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[0033]

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Where R¹, R^Two, R^Three, R^Four: Same or different
May be a hydrogen atom, -R ⁰-COO-A⁰if
Kuha B⁰Group, R¹: Al optionally having a substituent having 2 or more carbon atoms
Xylene group, R_Two~ R₈, R_Ten~ R₁₄, R₁₆, R₁₈~ R₂₀, R_{twenty three}~
R₃₁: May be the same or different, hydrogen atom, hydroxyl group,
Alkyl group, cycloalkyl group, alkoxy group, acyloxy group
Si group, aryl group, aryloxy group, aralkyl group,
Aralkyloxy group, halogen atom, R₉: Single bond, alkylene group, or

[0035]

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R ₁₅ , R ₁₇ : may be the same or different, single bond, alkylene group, --O--, --S--, R ₂₁ , R ₂₂ : may be the same or different, methylene group, lower alkyl-substituted methylene Group, halomethylene group, provided that the lower alkyl group in the present application refers to an alkyl group having 1 to 4 carbon atoms, R _{32 to} R ₃₅ : may be the same or different and each is a hydrogen atom,
Hydroxyl group, halogen atom alkyl group, cycloalkyl group,
Alkoxy group, aralkyl group, aralkyloxy group, acyloxy group, aryl group, aryloxy group, provided that each of the four substituents having the same symbol does not have to be the same group, B: single bond, or -O- , A: methylene group, lower alkyl-substituted methylene group, halomethylene group, az, a1 to h1: when more than one, the groups in parentheses may be the same or different, aq, s, t, v ~ Y, a1 to c1, e1, g1: 0 or an integer of 1 to 5, r, u, f1, h1: 0 or an integer of 1 to 4, z, d1, i1 to m1: 0 or an integer of 1 to 3 , I1 ~ j1, l1 ~
At least one of m1 is 1 or more, (a + b), (e + f + g), (k + l + m), (q + r + s), (w + x + y + z), (e1 + f1) ≧
2, (z + d1) ≤3, (r + u), (f1 + h1) ≤4, (a + c), (b + d), (e + h), (f + i), (g + j), (k + n), (l + o), (m + p), (q
+ t), (s + v), (w + a1), (x + b1), (y + c1), (e1 + g1) ≦ 5.

[0037]

[Chemical 6]

[0038]

[Chemical 7]

[0039]

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Specific examples of preferable compound skeletons are shown below.

[0041]

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[0042]

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[0043]

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[0044]

[Chemical 12]

[0045]

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[0046]

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[0047]

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[0048]

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[0049]

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[0050]

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[0051]

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R in the compounds (1) to (33) is a hydrogen atom,

[0053]

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Represents the following. However, at least two or three depending on the structure are groups other than hydrogen atoms, and each substituent R
Need not be the same group.

(B) Resin Insoluble in Water and Soluble in Alkaline Aqueous Solution (hereinafter, also referred to as alkali-soluble resin) (Compound of the present invention (a)) Examples of the alkali-soluble resin used in the present invention include novolac resin and hydrogen. Novolak resin, acetone-
Pyrogallol resin, o-polyhydroxystyrene, m-
Polyhydroxystyrene, p-polyhydroxystyrene, hydrogenated polyhydroxystyrene, halogen- or alkyl-substituted polyhydroxystyrene, hydroxystyrene-N-substituted maleimide copolymer, o / p- and m /
p-Hydroxystyrene Copolymer, Partial O-Alkyl Compound for Polyhydroxystyrene Hydroxyl Group (eg,
5 to 30 mol% of O-methyl compound, O- (1-alkoxy) -1-ethyl compound (as an alkoxy group, methoxy, ethoxy, propoxy, t-butoxy, cyclohexyloxy group, etc.), O-2-tetrahydro Pyranyl compound, O- (t-butoxycarbonyl) methyl compound, etc.) or O-acyl compound, (for example, 5 to 30 mol% O)
-Acetyl compound, O- (t-butoxy) carbonyl compound, etc.), styrene-maleic anhydride copolymer, styrene-
Examples thereof include, but are not limited to, a hydroxystyrene copolymer, an α-methylstyrene-hydroxystyrene copolymer, a carboxyl group-containing methacrylic resin and its derivative.

Particularly preferred alkali-soluble resins are novolac resins and o-polyhydroxystyrenes, m-polyhydroxystyrenes, p-polyhydroxystyrenes and copolymers thereof, alkyl-substituted polyhydroxystyrenes, and partial O-s of polyhydroxystyrenes. These are alkylated or O-acylated products, styrene-hydroxystyrene copolymers, and α-methylstyrene-hydroxystyrene copolymers. The novolak resin is obtained by subjecting a given monomer as a main component to addition condensation with an aldehyde in the presence of an acidic catalyst.

As the predetermined monomer, phenol, m
Cresols such as -cresol, p-cresol and o-cresol, xylenols such as 2,5-xylenol, 3,5-xylenol, 3,4-xylenol and 2,3-xylenol, m-ethylphenol, p- Alkylphenols such as ethylphenol, o-ethylphenol, pt-butylphenol, p-octylphenol, 2,3,5-trimethylphenol, p-methoxyphenol, m-methoxyphenol, 3,5-dimethoxyphenol, Alkoxyphenols such as -methoxy-4-methylphenol, m-ethoxyphenol, p-ethoxyphenol, m-propoxyphenol, p-propoxyphenol, m-butoxyphenol and p-butoxyphenol, 2-methyl-4-isopropyl Fenault Bis-alkylphenols etc., m
Hydroxychloro compounds such as -chlorophenol, p-chlorophenol, o-chlorophenol, dihydroxybiphenyl, bisphenol A, phenylphenol, resorcinol, and naphthol can be used alone or as a mixture of two or more, but are not limited thereto. It is not something to be done.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-
Phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o -Methylbenzaldehyde, m-methylbenzaldehyde,
p-Methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde, furfural, chloroacetaldehyde, and their acetal compounds, such as chloroacetaldehyde diethyl acetal, among which formaldehyde is used Is preferred.

These aldehydes may be used alone or in combination of two or more. As the acidic catalyst, hydrochloric acid, sulfuric acid, formic acid, acetic acid, oxalic acid and the like can be used.

The novolak resin thus obtained preferably has a weight average molecular weight in the range of 1,000 to 30,000. If it is less than 1,000, the film loss of the unexposed portion after development is large, and if it exceeds 30,000, the developing speed is reduced. Particularly preferred are 2,000-20,
The range is 000. The weight average molecular weight of the polyhydroxystyrene other than the novolac resin, its derivative, and the copolymer is 2,000 or more, preferably 500.
0-200000, more preferably 10,000-100
000. Further, from the viewpoint of improving the heat resistance of the resist film, 25000 or more is preferable. From the same viewpoint, the dispersity (M _w / M _n ) is preferably 1.8 _.
Or less, and more preferably _1. 5 or less.

Here, the weight average molecular weight is defined by the polystyrene conversion value of gel permeation chromatography.

In the present invention, these alkali-soluble resins may be used as a mixture of two or more kinds. The amount of the alkali-soluble resin used is 50 to 89.5% by weight, preferably 55 to 85% by weight, more preferably 60 to 80% by weight, based on the total weight of the photosensitive composition (excluding the solvent). .

(C) Compound which generates an acid upon irradiation with actinic rays or radiation (compound of the present invention (b)) The compound used in the present invention which decomposes upon irradiation with actinic rays or radiation to generate an acid includes: , A photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or a compound capable of generating an acid by known light used in a microresist or the like, and The mixture can be appropriately selected and used.

For example, SISchlesinger, Photogr.Sci.E
ng., 18,387 (1974), TSBal etal, Polymer, 21,423 (198
0) etc., U.S. Pat.No.4,069,055
No. 4,069,056, Re 27,992, Japanese Patent Application No. 3-140,140
Salt, DCNecker etal, Macrom
olecules, 17, 2468 (1984), CSwen et al, Teh, Proc. Con
f.Rad.Curing ASIA, p478 Tokyo, Oct (1988), U.S. Patent No.
Nos. 4,069,055 and 4,069,056, and phosphonium salts described in JVCrivello et al., Macromorecules, 10 (6), 1307 (19
77), Chem. & Eng. News, Nov. 28, p31 (1988), European Patent No. 10
No. 4,143, U.S. Pat.Nos. 339,049, 410,201, JP-A-2-150,848, Iodonium salts described in JP-A-2-296,514, etc., JVCrivello et al., Polymer J. 17, 73 (1985),
JVCrivello et al. J. Org.Chem., 43, 3055 (1978), WR
Watt et al, J. Polymer Sci., Polymer Chem. Ed., 22,1789
(1984), JVCrivello etal, Polymer Bull., 14,279 (198
5), JVCrivello etal, Macromorecules, 14 (5), 1141 (19
81), JVCrivello etal, J. PolymerSci., Polymer Chem.
Ed., 17, 2877 (1979), European Patent No. 370,693, and 3,902, 11
4, 233,567, 297,443, 297,442, U.S. Patents 4,933,377, 161,811, 410,201, 339,049.
Nos. 4,760,013, 4,734,444, 2,833,827,
Dokoku Patent Nos. 2,904,626, 3,604,580, 3,604,581
Sulfonium salts, JVCrivello et al, Macr
omorecules, 10 (6), 1307 (1977), JVCrivello et al, JP
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JP-A-60-239736, JP-A-61-169835, JP-A-61-169
837, JP 62-58241, JP 62-212401, JP
63-70243, organic halogen compounds described in JP-A-63-298339, K. Meier et al, J. Rad. Curing, 13 (4), 26 (198
6), TPGill et al, Inorg. Chem., 19,3007 (1980), DA
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Organometallics / organic halides described in No. 45, S. Hayase
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0,750, 046,083, 156,535, 271,851, and
0,388,343, U.S. Pat.Nos. 3,901,710, 4,181,531
M.TU, a photoacid generator having a 0-nitrobenzyl type protecting group described in JP-A No. 60-198538, JP-A No. 53-133022, etc.
NOOKA et al, Polymer Preprints Japan, 35 (8), G. Berner
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5, No. 199,672, No. 044,115, No. 0101,122, U.S. Patent Nos. 4,618,564, 4,371,605, 4,431,774,
JP-A-64-18143, JP-A-2-245756, Japanese Patent Application No. 3-140109
No. 61-166544, which is a compound capable of generating a sulfonic acid by photolysis, represented by iminosulfonates described in JP-A No. 61-166544.
And the disulfone compounds described in JP-A No. 1994-242242.

Further, a group that generates an acid by these lights,
Alternatively, a compound in which a compound is introduced into the main chain or side chain of a polymer, for example, ME Woodhouse et al., J. Am. Chem.
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id Commun., 9,625 (1988), Y.Yamadaetal, Makromol.Che
m., 152, 153, 163 (1972), JVCrivello etal, J. PolymerS
ci., Polymer Chem. Ed., 17, 3845 (1979), U.S. Pat.
No. 9,137, Dokoku Patent No. 3914407, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038
JP-A-63-163452, JP-A-62-153853, JP-A-63-163452
The compounds described in 146029 and the like can be used.

Further, VNRPillai, Synthesis, (1), 1 (198
0), A. Abad etal, Tetrahedron Lett., (47) 4555 (1971),
Compounds that generate an acid by light described in DHR Barton et al., J. Chem. Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, and EP 126,712 can also be used.

Among the compounds which decompose to generate an acid upon irradiation with actinic rays or radiation, those which are particularly effectively used are described below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PA)
An S-triazine derivative represented by G2).

[0068]

[Chemical 21]

In the formula, R ¹ represents a substituted or unsubstituted aryl group or alkenyl group, and R ² represents a substituted or unsubstituted aryl group, alkenyl group, alkyl group or --CY ₃ . Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0070]

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[0071]

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[0072]

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(2) An iodonium salt represented by the following formula (PAG3) or a sulfonium salt represented by the following formula (PAG4).

[0074]

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Here, the formulas Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group. Preferred substituents include an alkyl group, a haloalkyl group, a cycloalkyl group, an aryl group, an alkoxy group, a nitro group, a carboxyl group, an alkoxycarbonyl group, a hydroxy group, a mercapto group, and a halogen atom.

R ³ , R ⁴ and R ⁵ each independently represent a substituted or unsubstituted alkyl group or aryl group. Preferred are an aryl group having 6 to 14 carbon atoms, an alkyl group having 1 to 8 carbon atoms, and substituted derivatives thereof. Preferred substituents are an alkoxy group having 1 to 8 carbon atoms, an alkyl group having 1 to 8 carbon atoms, a nitro group, a carboxyl group, a hydroxy group and a halogen atom for the aryl group, and a substituent for the alkyl group. It is an alkoxy group having 1 to 8 carbon atoms, a carboxyl group, or an alkoxycarbonyl group.

[0077] Z ^- represents a counter anion, for example BF ₄ ^{-,
_{AsF 6 -, PF 6 -,}} SbF 6 -, SiF 6 2-, ClO 4 -,
CF ₃ SO ₃ ^-, etc. perfluoroalkane sulfonate anion, pentafluorobenzenesulfonic acid anion, condensed polynuclear aromatic sulfonic acid anion such as naphthalene-1-sulfonic acid anion, anthraquinone sulfonic acid anion, a sulfonic acid group-containing dyes Examples include, but are not limited to:

Two of R ³ , R ⁴ , and R ⁵ and A
r ¹ and Ar ² may be bonded to each other via a single bond or a substituent.

Specific examples include the compounds shown below, but the invention is not limited thereto.

[0080]

[Chemical formula 26]

[0081]

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[0082]

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[0083]

[Chemical 29]

[0084]

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[0085]

[Chemical 31]

[0086]

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[0087]

[Chemical 33]

[0088]

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[0089]

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[0090]

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[0091]

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The onium salts represented by the general formulas (PAG3) and (PAG4) are known, and for example, JWKnapcz.
yk et al., J. Am. Chem. Soc., 91, 145 (1969), ALMaycok et.
al, J. Org. Chem., 35, 2532, (1970), E. Goethas et al., Bul
l.Soc.Chem.Belg., 73,546, (1964), HMLeicester, JA
me.Chem.Soc., 51,3587 (1929), JVCrivello etal, J.Po
Lym.Chem.Ed., 18,2677 (1980), U.S. Pat.No. 2,807,648
No. 4,247,473 and JP-A No. 53-101,331, and the like.

(3) A disulfone derivative represented by the following general formula (PAG5) or an iminosulfonate derivative represented by the general formula (PAG6).

[0094]

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In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group. R ⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, or arylene group. Specific examples include the following compounds, but are not limited thereto.

[0096]

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[0097]

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[0098]

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[0099]

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[0100]

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The amount of the compound which decomposes upon irradiation with actinic rays or radiation to generate an acid is usually 0.5 based on the total weight of the photosensitive composition (excluding the coating solvent).
It is used in the range of 10 to 10% by weight, preferably 1 to 8% by weight, more preferably 1 to 5% by weight.

In the photosensitive composition of the present invention, if necessary,
Further, a dye, a pigment, a plasticizer, a surfactant, a photosensitizer, and a compound having two or more phenolic OH groups for promoting solubility in a developer, and JP-A-63-14964.
No. 0, JP-A-5-232706 and JP-A-5-249662.
No. 5-127369, No. 6-266110, and No. 6-266111, a basic compound (amine compound) for suppressing performance fluctuation with time after exposure can be contained.

Suitable dyes include oily dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 60.
3. Oil black BY, oil black BS, oil black T-505 (all manufactured by Orient Chemical Co., Ltd.), crystal violet (CI42555), methyl violet (CI42535), rhodamine B
(CI45170B), malachite green (CI42
000), methylene blue (CI52015) and the like.

Further, the photosensitive composition of the present invention can be obtained by adding a spectral sensitizer as described below and sensitizing it to a wavelength region longer than deep ultraviolet where the photo-acid generator used has no absorption. Sensitivity can be imparted to the i or g line. Suitable spectral sensitizers include, specifically, benzophenone,
p, p'-tetramethyldiaminobenzophenone, p,
p'-tetraethylethylaminobenzophenone, 2-
Chlorothioxanthone, anthrone, 9-ethoxyanthracene, anthracene, pyrene, perylene, phenothiazine, benzyl, acridine orange, benzoflavin, setoflavin-T, 9,10-diphenylanthracene, 9-fluorenone, acetophenone, phenanthrene, 2-nitrofluorene, 5-nitroacenaphthene, benzoquinone, 2-chloro-4-nitroaniline,
N-acetyl-p-nitroaniline, p-nitroaniline, N-acetyl-4-nitro-1-naphthylamine, picramide, anthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone 1,2-benzanthraquinone, 3-methyl-1,3-diaza-1,
9-benzanthrone, dibenzalacetone, 1,2-
Naphthoquinone, 3,3′-carbonyl-bis (5,7-
Dimethoxycarbonylcoumarin) and coronene, but are not limited thereto.

The photosensitive composition of the present invention is dissolved in a solvent that dissolves each of the above components and applied onto a support. As the solvent used here, ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate,
Ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable, and these solvents are used alone or in combination.

A surfactant may be added to the above solvent. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether,
Polyoxyethylene alkyl allyl ethers such as polyoxyethylene nonylphenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, Sorbitan fatty acid esters such as sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate Surfactants such as polyoxyethylene sorbitan fatty acid esters such as acrylates and the like, F-top EF301, E 303, EF352 (manufactured by Shin Akita Kasei Co., Ltd.), Megafac F171, F173 (manufactured by Dainippon Ink Co., Ltd.), Flora - de FC430, FC43
1 (manufactured by Sumitomo 3M Limited), Asahi Guard AG71
0, Surflon S-382, SC101, SC102,
Fluorinated surfactants such as SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), and acrylic or methacrylic (co) polymerized polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like. The amount of these surfactants is usually 2 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the solids in the composition of the present invention.

These surfactants may be added alone or in some combinations.

The photosensitive composition is applied onto a substrate (eg, silicon / silicon dioxide coating) used for the production of precision integrated circuit devices by an appropriate coating method such as a spinner or coater, and then passed through a predetermined mask. A good resist pattern can be obtained by exposing, baking and developing.

The developer for the photosensitive composition of the present invention is
Sodium hydroxide, potassium hydroxide, sodium carbonate,
Inorganic alkalis such as sodium silicate, sodium metasilicate and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, and triethylamine and methyldiethylamine Use alkaline aqueous solutions such as triamines, alcoholamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, and cyclic amines such as pyrrole and pichelidine. be able to.

Further, alcohols and surfactants may be added in appropriate amounts to the above alkaline aqueous solution before use. Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0111]

【Example】

[Synthesis Example-1 of Dissolution Inhibitor Compound] Tris (2-methyl-4-hydroxy-5-cyclohexylphenyl)-
Tetrahydrofuran 40 with 1,1,3-butane 30.9 g
It was dissolved in 0 ml. 11.2 g of potassium tert-butoxide was added to this solution under a nitrogen atmosphere, and after stirring at room temperature for 10 minutes,
24 g of di-tert-butyl dicarbonate were added.
The reaction was allowed to proceed at room temperature for 3 hours, the reaction solution was poured into ice water, and the product was extracted with ethyl acetate. The ethyl acetate layer was further washed with water and dried, after which the solvent was distilled off. The obtained crystalline solid was recrystallized (diethyl ether) and dried to obtain 35 g of a compound example (5: R is H or t-BOC group).

[Synthesis Example-2 of Dissolution Inhibitor Compound] 30.9 g of tris (2-methyl-4-hydroxy-5-cyclohexylphenyl) -1,1,3-butane was dissolved in 400 ml of diethyl ether. This solution was t
-Butyl vinyl ether (16.5 g) and a catalytic amount of P-toluenesulfonic acid were added, and the mixture was reacted at room temperature for 1 hour under reflux. After completion of the reaction, a small amount of sodium hydroxide was added and the mixture was filtered. The solvent of the filtrate was distilled off, and the obtained product was purified by column chromatography and dried to obtain a compound example (5:
All R-obtained 1-butoxy-1-ethyl groups).

[Synthesis Example-3 of Dissolution Inhibitor Compound] 2,6
-Bis (2-hydroxy-5-cyclohexylphenylmethyl) -4-methylphenol A solution of 24.2 g of N, N-dimethylacetamide in 200 ml of potassium carbonate 2
2.8 g and t-butyl bromoacetate 31.2 g were added, and the mixture was stirred at 120 ° C. for 7 hours. Then, the reaction mixture was poured into 2 l of water and extracted with ethyl acetate. After drying over magnesium sulfate, the extract was concentrated and subjected to column chromatography (carrier: silica gel, developing solvent: ethyl acetate /
As a result of purification with n-hexane = 2/8 (volume ratio), 37 g of a pale yellow solid was obtained. It was confirmed by NMR that this was a compound example (8: all R are —CH ₂ COOC ₄ H ₉ ^t groups).

[Synthesis Example-4 of Dissolution Inhibitor Compound] Tetrakis (3-cyclohexyl-4-hydroxyphenyl)
To a solution of 38.4 g of 1,1,5,5-pentane in 300 ml of N, N-dimethylacetamide, potassium carbonate 22.
8 g, and then t-butyl bromoacetate 31.2 g was added,
The mixture was stirred at 120 ° C for 7 hours. Then, the reaction mixture was poured into 3 l of water and extracted with ethyl acetate. After drying over magnesium sulfate, the extract was concentrated and subjected to column chromatography (carrier: silica gel, developing solvent: ethyl acetate / n
As a result of purification with -hexane = 2/8 (volume ratio), 55 g of a pale yellow powder was obtained. By NMR, this compound Example (14: R are all _{-CH 2 -COO-C 4 H 9} t group) was confirmed to be.

[Synthesis Example-5 of Dissolution Inhibitor Compound] Tetrakis (3-methyl-4-hydroxyphenyl) -1,1,
2,4-Cyclohexane 25.4 g was dissolved in dimethylacetamide 200 ml, and potassium carbonate 15.2 was added thereto.
g, and 19.5 g of t-butyl bromoacetate were added.
Then, it stirred at 120 degreeC for 5 hours. The reaction mixture was neutralized with acetic acid, poured into 2 l of ion-exchanged water, and extracted with ethyl acetate.

The ethyl acetate extract was concentrated and purified by column chromatography (carrier: silica gel, developing solvent: ethyl acetate / n-hexane = 1/5 (volume ratio)). As a result, the compound example (17: R is H or -CH ₂ -COO-
31 g of C ₄ H ₉ ^t group) was obtained.

Examples 1 to 8 Resists were prepared using the compounds of the present invention shown above. Table 1 shows the formulation at that time and the compound of the present invention used. Comparative Examples 1 and 2 Using the compound examples (20) and (62) described in JP-A-6-51519, resists were prepared in the same manner as in the examples. Table 1 shows the prescription at that time
Shown in Comparative Examples 3 and 4 According to the method described in US Pat. No. 4,491,628, t-butoxycarbonyloxystyrene polymer and t-butoxycarbonyloxy-α-methylstyrene polymer were synthesized to prepare two components. A system positive resist was prepared. The prescription at that time is shown in Table 1.

[0118]

[Table 1]

The abbreviations used in Table 1 have the following meanings. [Alkali-soluble resin] HS / St: 4-hydroxystyrene / styrene = 85/15 (molar ratio) copolymer (weight average molecular weight 35,000) HS / AcS: 4-hydroxystyrene / styrene = 80/20 ( Molar ratio) copolymer (weight average molecular weight 12,000) HS / BCMS: 4-hydroxystyrene / t-butoxycarbonylmethoxy styrene ^{* 1)} = 80/20 (molar ratio) copolymer (weight average molecular weight 13 HS / BES: 4-hydroxystyrene / t-butoxy-1-ethoxystyrene ^{* 2)} = 80/20 (molar ratio) copolymer (weight average molecular weight 12,000) BOCS: t-butoxycarbonyloxy Polymer of styrene ^{* 3)} (number average molecular weight 21,600) BAMS: t-butoxycarbonyloxy-α-methyls Polymer of Tylene (Number average molecular weight 46,900)

[0120]

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[0121] [dissolution inhibitor in the acid-decomposable group] _{BOC: -O-COO-C 4} H 9 t BCM: -O-CH 2 -COO-C 4 H 9 t BE: -OCH (CH 3) -O -C ₄ H ₉ ^t MM: each material shown in [preparation and evaluation of photosensitive composition] table 1 -OCH ₂ -O-CH ₃ was dissolved in propylene glycol monomethyl ether acetate 8 g, filtered through a 0.1μm filter Then, a resist solution was prepared. This resist solution was applied on a silicon wafer using a spin coater with a rotation speed of 3000 rpm and dried on a vacuum adsorption type hot plate at 120 ° C. for 60 seconds to obtain a resist film having a thickness of 0.84 μm. .

This resist film was exposed using a 248 nm KrF excimer laser stepper (NA = 0.45). After the exposure, the film was heated on a vacuum adsorption type hot plate at 100 ° C. for 60 seconds, immediately immersed in a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds, rinsed with water for 30 seconds and dried. The pattern on the silicon wafer thus obtained was observed with a scanning electron microscope to evaluate the resist profile. The results are shown in Table 2.

The sensitivity was defined as the reciprocal of the exposure amount for reproducing a 0.40 μm mask pattern, and was shown by the relative value of the sensitivity of Comparative Example 1. The film shrinkage is expressed as a percentage of the ratio of the film thickness before and after exposure and baking in the exposed area. The resolving power indicates a limit resolving power at an exposure amount for reproducing a 0.40 μm mask pattern.

From the results shown in Table 2, it is understood that the resist of the present invention has a good pattern profile and high resolution and sensitivity.

[0125]

[Table 2]

[0126]

The chemically amplified positive photosensitive composition of the present invention exhibits a good pattern profile and has high resolution and high sensitivity.

Front page continuation (72) Inventor Toru Fujimori 4,000 Kawajiri, Yoshida-cho, Haibara-gun, Shizuoka Prefecture Fuji Shashin Film Co., Ltd.

Claims (1)

[Claims] 1. (a) 50 to 89.5% by weight of a resin insoluble in water and soluble in an alkaline aqueous solution, (b) 0.5 to 10% by weight of a compound capable of generating an acid upon irradiation with actinic rays or radiation, and (C) At least one selected from the following (i) and (ii)
10 to 45% by weight of a low molecular weight acid-decomposable dissolution-inhibiting compound having a molecular weight of 3000 or less, which has a structure of a species and whose solubility in an alkali developing solution is increased by the action of an acid, and (i) is a group decomposable by an acid. A structure (ii) having at least two and having at least 10 bond atoms excluding the acid-decomposable group at the farthest position between the acid-decomposable groups (ii) at least three groups decomposable by an acid A positive photosensitive composition having a structure in which the distance between the acid-decomposable groups is at the farthest position and the number of bonding atoms excluding the acid-decomposable group is 9 or more. A positive photosensitive composition, wherein the dissolution inhibiting compound (c) has a molar absorption coefficient ε at 248 nm of 3,000 or less.