JP2001133981A - Positive type photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a positive type resist composition giving a photoresist which forms a rectangular pattern in the production of a semiconductor device and to obtain a positive type resist composition which ensures low edge roughness of a line pattern. SOLUTION: The positive type photoresist composition contains an acid decomposable polysiloxane having at least a structural unit of formula I (where L1 is-A1-OCO-,-A1-COO-,-A1-NHCO-,-A1-NHCOO-, -A1-NHCONH-, -A1-CONHor -A1-S-; A1 is at least one divalent combining group selected from alkylene, arylene and monocyclic and bridged alicyclic structures; M1 is a single bond or a divalent combining group which is alkylene, arylene or a monocyclic or bridged alicyclic structure; and R'-R''' are each alkyl, haloalkyl, halogen, alkoxy, trialkylsilyl or trialkylsilyloxy).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive photoresist composition used for manufacturing semiconductor integrated circuit elements, masks for manufacturing integrated circuits, printed wiring boards, liquid crystal panels, and the like.

As a pattern forming method for manufacturing electronic components such as a semiconductor element, a magnetic bubble memory, and an integrated circuit, a method utilizing a photoresist which is sensitive to ultraviolet rays or visible rays has been widely and practically used. I have. There are two types of photoresist: a negative type, in which the irradiated part is insoluble in the developer by light irradiation, and a positive type, in which the exposed part is solubilized.The negative type has higher sensitivity than the positive type and is necessary for wet etching. Until recently, photoresists occupied the mainstream because of their excellent adhesion to substrates and chemical resistance. However, with the increase in the density and integration of semiconductor devices and the like, the line width and spacing of patterns have become extremely small.
Since dry etching has been adopted for substrate etching, high resolution and high dry etching resistance have been demanded for photoresists, and the majority of positive photoresists are nowadays. Was. In particular, among the positive photoresists, they have excellent sensitivity, resolution and dry etching resistance. For example, JC Strieta, Kodak Microelectronics Seminar Proceedings, No. 11
6 (1976) (JC Strieter, Kodak Micro ele
ctronics Seminar Proceedings, 116 (1976)
And the like, alkali-developable positive photoresists based on alkali-soluble novolak resins are the mainstream of current processes.

However, in recent years, multifunctional electronic devices have been
As the sophistication increases, there is a strong demand for finer patterns to achieve higher densities and higher integration.

That is, since the vertical dimension of the integrated circuit is not much reduced as compared with the horizontal dimension of the integrated circuit, the ratio of the height to the width of the resist pattern has to be increased. For this reason, it has become more difficult to suppress the dimensional change of the resist pattern on a wafer having a complicated step structure as the pattern becomes finer. Further, in various types of exposure methods, there is a problem with the reduction of the minimum size. For example,
In light exposure, the interference effect of reflected light due to the step of the substrate has a great effect on dimensional accuracy, whereas in electron beam exposure, the proximity effect caused by backscattering of electrons causes the fine resist pattern The height to width ratio can no longer be increased.

It has been found that many of these problems are eliminated by using a multilayer resist system. For a description of multilayer resist systems, see Solid State Technology, 74 (1981) [Solid State Technolog
y, 74 (1981)], but many other studies on this system have been published. Generally, a multilayer resist method includes a three-layer resist method and a two-layer resist method. In the three-layer resist method, an organic flattening film is applied on a stepped substrate, an inorganic intermediate layer and a resist are stacked thereon, and the resist is patterned. Then, the inorganic intermediate layer is dry-etched using the resist as a mask. This is a method of patterning an organic flattening film by O2 RIE (reactive ion etching) using the inorganic intermediate layer as a mask. Basically, this method has been studied from an early stage because conventional techniques can be used, but the process is very complicated, or the organic film, the inorganic film, and the organic film have different three-layer physical properties. The problem is that cracks and pinholes are likely to occur in the intermediate layer due to the overlapping of the objects.

In contrast to the three-layer resist method, the two-layer resist method uses a resist having both properties of the resist and the inorganic intermediate layer in the three-layer resist method, that is, a resist having oxygen plasma resistance. In addition, the generation of cracks and pinholes is suppressed, and the process is simplified because the number of layers is reduced from three to two. However, in the three-layer resist method, a conventional resist can be used as the upper resist, whereas in the two-layer resist method, there is a problem that a new resist having oxygen plasma resistance has to be developed.

[0007] From the above background, it has excellent oxygen plasma resistance which can be used as an upper layer resist such as a two-layer resist method.
There has been a demand for the development of a high-sensitivity, high-resolution positive photoresist, in particular, an alkali developing type resist that can be used without changing the current process.

Further, in the manufacture of VLSI, which requires processing of an ultrafine pattern having a line width of half a micron or less, the wavelength used by an exposure apparatus used for lithography has been shortened, and now a KrF excimer laser beam is used. The use of ArF excimer laser light has been studied. In such short wavelength optical lithography, a resist generally called a chemically amplified type is used. In particular, when an ArF excimer laser beam is used, it is not appropriate to introduce a phenol structure into a binder resin, which is a main component of the resist, from the viewpoint of optical transparency of the film. In general, a resin polymer containing, as an image-forming portion, a structure capable of decomposing with an acid to generate a carboxylic acid, such as an ester, a 1-alkyladamantyl ester, or a THP-protected carboxylic acid, is used as a binder. Polysiloxane containing an image-forming portion transparent to ArF excimer laser light is disclosed in, for example, JP-A-8-16.
0623, JP-A-10-324748, JP-A-11-324
-60733 and JP-A-11-60734.

[0009] However, these resists have poor rectangularity of the pattern for processing ultra-fine patterns and poor edge roughness of line patterns, and furthermore, in the next oxygen plasma process, dimensional shifts occur during pattern transfer to a lower layer. Has a problem that the size becomes larger.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a positive resist composition that provides a photoresist that forms a rectangular pattern in the manufacture of semiconductor devices. Another object of the present invention is to provide a positive resist composition having a small edge roughness of a line pattern. Still another object of the present invention is to provide a positive resist composition having a small dimensional shift when transferring a pattern to a lower layer in an oxygen plasma etching step.

[0011]

Means for Solving the Problems As a result of intensive studies on the resist composition in a positive-type chemical amplification system, the present inventors have found that the use of an acid-decomposable resin copolymerized with a specific repeating unit enables the present invention to be used. I found that my goal was achieved. That is, the above object is achieved by using a positive photoresist composition containing the following acid-decomposable resin.

(1) A positive photoresist composition comprising at least an acid-decomposable polysiloxane having a structural unit represented by the following general formula (I).

[0013]

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In the formula (I), L ¹ is -A ¹ -OCO-, -A
¹ -COO-, -A ¹ -NHCO-, -A ¹ -NHCOO
-, -A ¹ -NHCONH-, -A ¹ -CONH-, -A
¹ -OCONH- or an -A ¹ -S-. A ¹ represents an alkylene group, an arylene group, and at least one divalent linking group selected from monocyclic and bridged alicyclic structures.
M ¹ represents a single bond, an alkylene group, an arylene group, or a divalent linking group having a monocyclic or bridged alicyclic structure. R ′ to R ′ ″ each independently represent an alkyl group, a haloalkyl group, a halogen atom, an alkoxy group, a trialkylsilyl group or a trialkylsilyloxy group.

(2) The positive photoresist composition according to the above (1), wherein the acid-decomposable polysiloxane further contains a repeating structural unit represented by the following general formula (II).

[0016]

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In the formula (II), L ² is a single bond, -A ² -OC
^{O -, - A 2 -COO -} , - A 2 -NHCO -, - A 2 -
^{NHCOO -, - A 2 -NHCONH -} , - A 2 -CON
H -, - A ² -OCONH- or -A represents a ² -S-. A
² represents a single bond, an alkylene group or an arylene group.
M ² represents an aryl group, an aralkyl group, or a monocyclic or bridged alicyclic group.

(3) The positive photoresist composition as described in the above (1) or (2), wherein the acid-decomposable polysiloxane further contains a repeating structural unit represented by the following general formula (III): .

[0019]

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(4) (A) the acid-decomposable polysiloxane according to any of the above (1) to (3), (B) a compound which decomposes upon irradiation with actinic rays or radiation to generate an acid,
(C) an organic solvent capable of dissolving the above (A) and (B); (D) an organic basic compound soluble in the organic solvent (C); and (E) a surfactant. Characteristic positive photoresist composition.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the polysiloxane of the present invention will be described. In the general formula (I), L ¹ is -A ¹ -O
^{CO -, - A 1 -COO -} , - A 1 -NHCO -, - A 1
-NHCOO-, -A ¹ -NHCONH-, -A ¹ -CO
NH -, - A ¹ -OCONH- or an -A ¹ -S-.
A ¹ represents an alkylene group, an arylene group, and at least one divalent linking group selected from monocyclic and bridged alicyclic structures. In the A ^1, an alkylene group, for example, linear or branched alkylene group having 1 to 10 carbon atoms, preferably straight-chain or branched alkylene group having 1 to 6 carbon atoms, particularly preferably Is a methylene group, an ethylene group or a propylene group. Specific examples of the arylene group include an o-phenylene group, an m-phenylene group, and a p-phenylene group. In the above A ¹ , examples of the monocyclic or bridged alicyclic structure include those shown below.

[0022]

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[0023]

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M ¹ represents a single bond, an alkylene group, an arylene group, or a divalent linking group having a monocyclic or bridged alicyclic structure. Here, the alkylene group has 1 to 10 carbon atoms.
Linear and branched alkylene groups. It is preferably a linear or branched alkylene group having 1 to 6 carbon atoms, particularly preferably an arylene group which is a methylene group, an ethylene group or a propylene group, or a monocyclic or bridged alicyclic structure. Examples of the divalent linking group represented by are the same as those described for A ¹ .

R ′ to R ′ ″ each independently represent an alkyl group,
And a group selected from a haloalkyl group, a halogen atom, an alkoxy group, a trialkylsilyl group, and a trialkylsilyloxy group. The alkyl group may have 1 to 1 carbon atoms.
A linear or branched alkyl group of 0 is preferable, a linear or branched alkyl group having 1 to 6 carbon atoms is more preferable, and a methyl group, an ethyl group, an n-propyl group, an i-propyl group, n-butyl group, i-butyl group, s
-Butyl group and t-butyl group. Examples of the haloalkyl group include a chloromethyl group, a bromomethyl group, and an iodomethyl group. The alkoxy group may have 1 to 6 carbon atoms.
Linear or branched alkyl groups, more preferably methoxy, ethoxy, n-propyloxy, i-
Propyloxy group, n-butoxy group, i-butoxy group,
An s-butoxy group and a t-butoxy group, among which methoxy and ethoxy groups are particularly preferred.

The alkyl group of the trialkylsilyl group is a linear or branched alkyl group having 1 to 6 carbon atoms,
More preferably a methyl group, an ethyl group, an n-propyl group,
Among them, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group and a t-butyl group, among which a methyl group is most preferred. The alkyl group of the trialkylsilyloxy group is a linear or branched alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, i-butyl group, s
-Butyl group and t-butyl group, and among them, the most preferred is a methyl group.

In the general formula (II), L ² is a single bond,
^{-A 2 -OCO -, - A 2} -COO -, - A 2 -NHCO
^{-, - A 2 -NHCOO -,} - A 2 -NHCONH -, -
^{A 2 -CONH -, - A 2} -OCONH- or -A ² -S
Represents-. A ² represents a single bond, an alkylene group or an arylene group. M ² represents an aryl group, an aralkyl group, or a monocyclic or bridged alicyclic group. In the A ^2, alkylene groups include straight or branched alkylene group having 1 to 10 carbon atoms. It is preferably a linear or branched alkylene group having 1 to 6 carbon atoms, and particularly preferably a methylene group, an ethylene group or a propylene group. Similarly, examples of the arylene group include an o-phenylene group, an m-phenylene group, and a p-phenylene group. In the above M ^2, the aryl group, phenyl group which may have a substituent can be given as specific examples. Similarly, the aralkyl group includes a benzyl group.

Examples of the monocyclic or bridged alicyclic structure of A ² and M ² include those similar to the examples of the monocyclic or bridged alicyclic structure of M ¹ .

The general formula (III) is a siloxane structural unit derived from tetrachlorosilane, tetrahydrosilane and tetraalkoxysilane. Among them, tetramethoxysilane and tetraethoxysilane are preferable as tetrachlorosilane and tetraalkoxysilane.

The acid-decomposable polysiloxane of the present invention preferably contains 10 to 100 mol%, more preferably 30 to 70 mol%, of the unit represented by formula (I). Further, in the acid-decomposable polysiloxane of the present invention containing the structure of the general formula (II), the structure of the formula (II) is
It is preferably contained at 0 mol%, more preferably at 40 to 60 mol%. Further, the acid-decomposable polysiloxane of the present invention containing the structure of the general formula (III) preferably contains the structure of the formula (III) in an amount of 1 to 10 mol%, more preferably 2 to 5 mol%.

The acid-decomposable polysiloxane of the present invention has the following general formula (I) for controlling solvent solubility and alkali solubility.
The structural units of (V) and / or (V) may be co-condensed.

[0032]

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Here, W, W ¹ and W ² represent groups having neither alkali solubility nor acid decomposability. Specifically, it may have a linear group having 1 to 10 carbon atoms which may have a substituent, may have a branched group having 3 to 10 carbon atoms which may have a substituent, or may have a substituent. A cyclic alkyl group having 6 to 10 carbon atoms; an aryl group having 6 to 10 carbon atoms which may have a substituent; or an aralkyl group having 7 to 11 carbon atoms which may have a substituent. . Preferred specific examples of these groups include methyl, ethyl, n-propyl, i-propyl, n
-Butyl, i-butyl, t-butyl, n-pentyl, n
-Hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, cyclohexyl, phenyl, naphthyl, benzyl, naphthylmethyl.
The substituents of these groups include a halogen atom,
To 6 alkoxy groups, phenoxy groups, hydroxyl groups and the like. Note that W ¹ and W ² may be the same or different.

The acid-decomposable polysiloxane having the structural unit represented by the general formula (I) can be obtained by the following method. Trialkoxysilane or trichlorosilane linked with an alicyclic structure having an ethylenically unsaturated bond is converted to a trisubstituted silane having a corresponding R ′ to R ′ ″ in the presence of a chloroplatinic acid catalyst or a radical reaction initiator. Hydrosilylate the compound.

Thereafter, 1) a trialkoxysilane having a carboxyl group at the terminal is converted into a polysiloxane by heating in the presence of an acid and water or a base catalyst and water, and the carboxyl group is protected with an acid-decomposable group. 2) After synthesizing a trialkoxysilane having an acid-decomposable protected carboxyl group at the terminal, a base catalyst and water are added, and the mixture is heated to form a polysiloxane. Can be synthesized.

Alternatively, an acid-decomposable group-containing polysiloxane linked to an alicyclic structure having an ethylenically unsaturated bond is reacted with the corresponding R 'to R' in the presence of a chloroplatinic acid catalyst or a radical reaction initiator. There is also a method of hydrosilylating a trisubstituted silane compound having ''.

Examples of the method for introducing the acid-decomposable group include an acid-catalyzed reaction with a vinyl ether compound corresponding to the acid-decomposable group, di-t-butyl dicarbonate, trimethylsilyl chloride,
Alternatively, it can be obtained by using a known reaction such as a base catalyzed reaction with t-butyldimethylsilyl chloride.

The use of a siloxane unit having a structural unit represented by the above (IV) or (V) is preferable in view of solvent solubility, sensitivity, resolution, and rectangularity of a pattern.

Specific examples of the structural unit of the general formula (I) for the polysiloxane of the present invention are shown below, but the present invention is not limited to these.

[0040]

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[0041]

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With respect to the polysiloxane of the present invention, specific examples of the structural unit of the general formula (II) are shown below, but the present invention is not limited thereto.

[0043]

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The weight average molecular weight of the polysiloxane of the present invention is from 500 to 10,000 as a polystyrene equivalent value measured by gel permeation chromatography.
0 is preferable, 700 to 50,000 is more preferable, and 800 to 20,000 is particularly preferable.

Next, the positive composition of the present invention will be described. The positive photoresist composition of the present invention comprises (A) the acid-decomposable polysiloxane according to any one of the above (1) to (3), and (B) decomposed by irradiation with actinic rays or radiation to generate an acid. (C) an organic solvent capable of dissolving the above (A) and (B), and (D) an organic basic compound soluble in the organic solvent (C), and (E) ) It is preferable to contain a surfactant.

First, the compound (B) which generates an acid upon irradiation with actinic rays or radiation will be described. Examples of the compound used in the present invention, which decomposes upon irradiation with actinic rays or radiation to generate an acid, include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photobleaching agent for dyes, and a photodiscoloration agent. Agents or known light used for micro resists (ultraviolet rays of 400 to 200 nm, far ultraviolet rays, particularly preferably g-rays, i-rays, KrF excimer laser light, A
A compound capable of generating an acid by rF excimer laser light, electron beam, X-ray, molecular beam or ion beam, and a mixture thereof can be appropriately selected and used.

Compounds which generate an acid upon irradiation with actinic rays or radiation used in the present invention include, for example, SI
Schlesinger, Photogr. Sci. Eng., 18, 387 (1974),
TSBal et al, Polymer, 21, 423 (1980) and the like diazonium salts, U.S. Pat.Nos. 4,069,055 and 4,069,056
No. Re27,992, ammonium salts described in JP-A-3-140140, etc., DC Necker et al, Macromolecules, 17,
2468 (1984), CS Wenet al, Teh, Proc. Conf. Rad.
Curing ASIA, p478 Tokyo, Oct (1988), U.S. Patent No. 4,06
9,055, the phosphonium salts described in 4,069,056 and the like, J.
V. Crivello et al, Macromorecules, 10 (6), 1307 (19
77), Chem. & Eng. News, Nov. 28, p31 (1988), European Patent No. 104,143, U.S. Patent Nos. 339,049, 410,201.
Iodonium salts described in JP-A-2-150,848, JP-A-2-296,514, etc., JV Crivello etal, Polymer J. 1
7, 73 (1985), JV Crivello et al. J. Org. Chem.,
43, 3055 (1978), WR Watt et al, J. Polymer Sci.,
Polymer Chem. Ed., 22, 1789 (1984), JV Crivello
et al, Polymer Bull., 14, 279 (1985), JV Crivel
lo et al, Macromorecules, 14 (5), 1141 (1981), JV
Crivello et al, J. Polymer Sci., Polymer Chem. E
d., 17, 2877 (1979), European Patent Nos. 370,693, 161,81
No. 1, No. 410, 201, No. 339,049, No. 233,567, No. 297,
No. 443, No. 297,442, U.S. Pat.No. 3,902,114 No. 4,933,3
No. 77, No. 4,760,013, No. 4,734,444, No. 2,833,827
No. 2,904,626, 3,604,580, 3,604,
No. 581, JP-A-7-28237, sulfonium salts described in JP-A-8-27102, etc., JV Crivello et al, Macromorecules,
10 (6), 1307 (1977), JV Crivello et al, J. Polyme
r Sci., Polymer Chem. Ed., 17, 1047 (1979) and the like, CS Wen et al., Teh, Proc. Conf. R
ad. Curing ASIA, p478 Tokyo, Oct (1988), etc., onium salts such as arsonium salts, U.S. Pat.
No., JP-B-46-4605, JP-A-48-36281, JP-A-55-32
No. 070, JP-A-60-239736, JP-A-61-169835, JP-A-61-169837, JP-A-62-58241, JP-A-62-212401
No., JP-A-63-70243, organic halogen compounds described in JP-A-63-298339, etc., K. Meier et al, J. Rad.
13 (4), 26 (1986), TP Gill et al, Inorg.Chem.,
19, 3007 (1980), D. Astruc, Acc. Chem. Res., 19 (1
2), 377 (1896), and organometallic / organic halides described in JP-A-2-14145, S. Hayase et al, J. Polymer Sc
i., 25, 753 (1987), E. Reichmanis et al, J. Pholymer
Sci., Polymer Chem. Ed., 23, 1 (1985), QQ Zhu et.
al, J. Photochem., 36, 85, 39, 317 (1987), B. Amit
et al, Tetrahedron Lett., (24) 2205 (1973), DHR
Barton et al, J. Chem Soc., 3571 (1965), PM Colli
ns et al, J. Chem. Soc., PerkinI, 1695 (1975), M. Ru.
dinstein et al, Tetrahedron Lett., (17), 1445 (197
5), JW Walker et al, J. Am. Chem. Soc., 110, 7170
(1988), SC Busman et al, J. Imaging Technol., 11
(4), 191 (1985), HM Houlihan et al, Macormolecule
s, 21, 2001 (1988), PM Collins et al, J. Chem. S
oc., Chem. Commun., 532 (1972), S. Hayase et al, Mac
romolecules, 18, 1799 (1985); E. Reichman et al, J.
Electrochem. Soc., Solid State Sci. Technol., 130
(6), FM Houlihan et al, Macromolcules, 21, 2001
(1988), European Patent Nos. 0290,750, 046,083, 156,53
Nos. 5,271,851, 0,388,343, U.S. Pat.
No. 10, 4,181,531, JP-A-60-198538, JP-A-53-1
No. 33022, etc., a photoacid generator having a 0-nitrobenzyl-type protecting group, M. TUNOOKA et al, Polymer Preprints
Japan, 35 (8), G. Berneret al, J. Rad. Curing, 13
(4), WJ Mijs et al, Coating Technol., 55 (697),
45 (1983), Akzo, H. Adachi et al, Polymer Preprints,
Japan, 37 (3), European Patent Nos. 0199,672, 84,515,
044,115, 618,564, 0101,122, U.S. Pat.
Nos. 371,605 and 4,431,774, JP-A-64-18143, JP-A-Hei.
2-245756, compounds that generate sulfonic acid upon photodecomposition represented by iminosulfonate and the like described in JP-A-3-140109, JP-A-61-166544, JP-A-2-71270 and the like Disulfone compound described, JP-A-3-103854, 3-103856
And the diazoketosulfone and diazodisulfone compounds described in JP-A Nos. 4-210960 and 4-210960.

Further, a group which generates an acid by these lights,
Alternatively, a compound having a compound introduced into the main chain or side chain of a polymer, for example, ME Woodhouse et al, J. Am. Ch.
em. Soc., 104, 5586 (1982), SP Pappas et al, J. I.
maging Sci., 30 (5), 218 (1986), S. Kondo et al, Mak
romol. Chem., Rapid Commun., 9, 625 (1988), Y. Yama
da et al, Makromol.Chem., 152, 153, 163 (1972);
V. Crivello et al, J. Polymer Sci., Polymer Chem.
Ed., 17, 3845 (1979), U.S. Patent No. 3,849,137, Dokoku Patent No. 3,914,407, JP-A-63-26653, JP-A-55-164824.
No., JP-A-62-69263, JP-A-63-146038, JP-A-63-69263
Compounds described in JP-A-163452, JP-A-62-153853, JP-A-63-146029 and the like can be used.

Further, VNR Pillai, Synthesis, (1),
1 (1980), A. Abad et al, Tetrahedron Lett., (47) 45
55 (1971), DHR Barton et al, J. Chem. Soc.,
(C), 329 (1970), U.S. Patent 3,779,778, European Patent 1
Compounds that generate an acid by light described in No. 26,712 and the like can also be used.

Among the compounds capable of decomposing upon irradiation with actinic rays or radiation to generate an acid, those which are used particularly effectively 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).

[0051]

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In the formula, R ²⁰¹ is a substituted or unsubstituted aryl group or alkenyl group, and R ²⁰² is a substituted or unsubstituted aryl group, alkenyl group, alkyl group, —C (Y) ₃
Show Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0053]

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[0054]

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[0055]

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

[0057]

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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 ²⁰³ , R ²⁰⁴ and R ²⁰⁵ each independently represent a substituted or unsubstituted alkyl group or aryl group. Preferably, it is an aryl group having 6 to 14 carbon atoms, an alkyl group having 1 to 8 carbon atoms, or a substituted derivative thereof. Preferred substituents include an aryl group, 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, and an alkyl group is an alkoxy group having 1 to 8 carbon atoms, a carboxyl group and an alkoxycarbonyl group.

[0060] Z ^{chromatography} represents a counter anion, for example BF ₄ ^over,
AsF ₆ ^over, PF ₆ ^over, SbF ₆ ^over, SiF ₆ ^2-, ClO ₄ ^over,
CF ₃ SO ₃ ^over perfluoroalkanesulfonic acid anion such as, 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:

Further, two of R ²⁰³ , R ²⁰⁴ and R ²⁰⁵ and Ar ¹ and Ar ² may be bonded through a single bond or a substituent.

Specific examples include the following compounds, but are not limited thereto.

[0063]

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[0064]

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[0065]

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[0066]

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[0067]

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[0068]

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[0069]

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[0070]

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[0071]

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[0072]

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[0073]

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[0074]

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[0075]

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The above-mentioned onium salts represented by the general formulas (PAG3) and (PAG4) are known, for example, JW Knapcz
yk et al, J. Am. Chem. Soc., 91, 145 (1969), AL
Maycok et al, J. Org.Chem., 35, 2532, (1970), E.
Goethas et al, Bull.Soc.Chem.Belg., 73, 546, (19
64), HM Leicester, J. Ame. Chem. Soc., 51, 3587.
(1929), JV Crivello et al, J. Polym. Chem. Ed.,
18, 2677 (1980); U.S. Pat.Nos. 2,807,648 and 4,24
No. 7,473, and JP-A-53-101331 can be synthesized.

(3) Disulfone derivatives represented by the following formula (PAG5) or iminosulfonate derivatives represented by the following formula (PAG6).

[0078]

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In the formula, Ar^Three, Ar^FourAre each independently substituted
Or an unsubstituted aryl group. R ²⁰⁶Is replaced or
It represents an unsubstituted alkyl group or aryl group. A is a substitution
Or unsubstituted alkylene, alkenylene, arylene
Shows a substituent group. Specific examples include the compounds shown below.
However, the present invention is not limited to these.

[0080]

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[0081]

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[0082]

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[0083]

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[0084]

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[0085]

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(4) Diazosulfone Derivatives Examples of the diazodisulfone derivative compounds include those represented by the following general formula (PAG7).

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Here, R ²⁰⁷ and R ²⁰⁸ each independently represent an alkyl group which may have a substituent, a cycloalkyl group, or an aryl group which may have a substituent.
Here, the alkyl group is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and more preferably a linear or branched alkyl group having 1 to 12 carbon atoms. As the cycloalkyl group, a cyclopentyl group or a cyclohexyl group is preferable. As the aryl group, an aryl group which may have a substituent having 6 to 10 carbon atoms is preferable. Here, as the substituent, a methyl group, an ethyl group, an n-propyl group, an i-propyl group,
n-butyl group, i-butyl group, s-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-octyl group, 2-ethylhexyl group, nonyl group, decyl group, dodecyl group, etc. Examples thereof include an alkoxy group such as an alkyl group, a methoxy group, an ethoxy group, a propoxy group, and a butoxy group, a halogen atom, a nitro group, and an acetyl group.

Specific examples of the diazodisulfone derivative compound include the following compounds. Bis (methylsulfonyl) diazomethane, bis (ethylsulfonyl) diazomethane, bis (propylsulfonyl) diazomethane,
Bis (1-methylpropylsulfonyl) diazomethane,
Bis (butylsulfonyl) diazomethane, bis (1-methylbutylsulfonyl) diazomethane, bis (heptylsulfonyl) diazomethane, bis (octylsulfonyl) diazomethane, bis (nonylsulfonyl) diazomethane, bis (decylsulfonyl) diazomethane, bis (dodecylsulfonyl) Diazomethane, bis (trifluoromethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (benzylsulfonyl) diazomethane, bis (2-chlorobenzylsulfonyl) diazomethane, bis (4-chlorobenzylsulfonyl) diazomethane, bis (phenylsulfonyl) Diazomethane, bis (4-methoxyphenylsulfonyl)
Diazomethane, bis (2-methylphenylsulfonyl)
Diazomethane, bis (3-methylphenylsulfonyl)
Diazomethane, bis (4-methylphenylsulfonyl)
Diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, bis (2,5-dimethylphenylsulfonyl) diazomethane, bis (3,4-dimethylphenylsulfonyl) diazomethane, bis (2,4,6-
Trimethylphenylsulfonyl) diazomethane, bis (4-fluorophenylsulfonyl) diazomethane, bis (2,4-difluorophenylsulfonyl) diazomethane, bis (2,4,6-trifluorophenylsulfonyl) diazomethane, bis (4-nitrophenylsulfonyl) ) Diazomethane

Examples of the diazoketosulfone derivative compound include those represented by the following general formula (PAG8).

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Here, R ²⁰⁷ and R ²⁰⁸ are the same as those in (PAG7)
R ²⁰⁷ and R ²⁰⁸ have the same meanings. Specific examples of the diazoketosulfone derivative compound include the following compounds.

Methylsulfonyl-benzoyl-diazomethane, ethylsulfonyl-benzoyl-diazomethane, methylsulfonyl-4-bromobenzoyl-diazomethane, ethylsulfonyl-4-bromobenzoyl-
Diazomethane, phenylsulfonyl-benzoyl-diazomethane, phenylsulfonyl-2-methylphenyl-diazomethane, phenylsulfonyl-3-methylphenyl-diazomethane, phenylsulfonyl-4-methylphenyl-diazomethane, phenylsulfonyl-3-
Methoxyphenyl-diazomethane, phenylsulfonyl-4-methoxyphenyl-diazomethane, phenylsulfonyl-3-chlorobenzoyl-diazomethane, phenylsulfonyl-4-chlorophenyl-diazomethane, tolylsulfonyl-3-chlorobenzoyl-diazomethane, tolylsulfonyl-4-chlorophenyl -Diazomethane, phenylsulfonyl-4-fluorophenyl-diazomethane, tolylsulfonyl-4-fluorophenyl-diazomethane

As the acid generator, an organic sulfonic acid is generated by irradiation with actinic rays or radiation (B-3) to
The compound belonging to (B-6) is preferable because the rectangularity of the resist pattern and the edge roughness of the line pattern are good, and particularly the compounds belonging to (B-3) to (B-6) which generate a fluorinated organic sulfonic acid. Compounds are preferred because of their high sensitivity.

The amount of the photoacid generator (b) is usually in the range of 0.001 to 40% by weight based on the total weight of the positive photoresist composition of the present invention (excluding the coating solvent). It is preferably used in the range of 0.01 to 20% by weight, more preferably 0.1 to 5% by weight. If the amount of the compound that decomposes upon irradiation with actinic rays or radiation to generate an acid is less than 0.001% by weight, the sensitivity becomes low. If the amount is more than 40% by weight, the light absorption of the resist becomes high. This is not preferable because the profile is deteriorated and the process (especially baking) margin is narrowed.

Next, the (D) organic basic compound used in the present invention will be described. The composition of the present invention can contain an organic basic compound. This is preferable because the storage stability is improved and the line width change due to PED is reduced. Preferred organic basic compounds that can be used in the present invention are compounds that are more basic than phenol. Among them, a nitrogen-containing basic compound is preferable.
Preferred chemical environments include the structures of the following formulas (A) to (E).

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Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² are the same or different and are a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, a hydroxyalkyl having 1 to 6 carbon atoms. Group or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, wherein R ²⁵¹ and R ²⁵² may be bonded to each other to form a ring.

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In the above formula (E), R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ are the same or different and represent an alkyl group having 1 to 6 carbon atoms.

Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms having different chemical environments in one molecule, and particularly preferred is a ring structure containing a substituted or unsubstituted amino group and a nitrogen atom. Or a compound having an alkylamino group. Preferred specific examples are substituted or unsubstituted guanidine,
Substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazole, substituted or unsubstituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted Pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine, etc. Is mentioned. Preferred substituents are an amino group, aminoalkyl group, alkylamino group, aminoaryl group, arylamino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxyl group, cyano group It is.

Particularly preferred compounds are guanidine,
1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine , 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-
6-methylpyridine, 3-aminoethylpyridine, 4-
Aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2
-Aminoethyl) piperidine, 4-amino-2,2,
6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1 -P-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N-
(2-aminoethyl) morpholin, diazabicycloundecene (DBU), diazabicyclononene (DB
N), diazabicyclooctane and the like, but are not limited thereto.

These nitrogen-containing basic compounds are used alone or in combination of two or more. The amount of the nitrogen-containing basic compound to be used is the photosensitive resin composition (excluding the solvent) 1
The amount is usually 0.001 to 10 parts by weight, preferably 0.01 to 5 parts by weight, based on 00 parts by weight. If the amount is less than 0.001 part by weight, the above effects cannot be obtained. On the other hand, if it exceeds 10 parts by weight, the sensitivity tends to decrease and the developability of the unexposed part tends to deteriorate.

Next, the surfactant (E) used in the present invention will be described. The positive photoresist composition of the present invention may further contain, if necessary, two or more phenolic OH groups that promote solubility in a surfactant, a dye, a pigment, a plasticizer, a photosensitizer, and a developer. And the like can be contained.

Suitable surfactants are specifically polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether,
Polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene alkyl allyl ethers such as polyoxyethylene octyl phenol ether and polyoxyethylene nonyl phenol 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 Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; F-Top EF301, EF303;
EF352 (manufactured by Shin-Akita Chemical Co., Ltd.), MegaFac F1
71, F173 (manufactured by Dainippon Ink Co., Ltd.), Florado FC430, FC431 (manufactured by Sumitomo 3M Limited),
Asahi Guard AG710, Surflon S-382, SC
101, SC102, SC103, SC104, SC1
05, SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid or methacrylic acid (co) polymerized polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like.

These surfactants may be added alone or in some combination. A preferable addition amount is 100 parts of the composition (excluding the solvent).
0.0005 to 0.01 parts by weight with respect to parts by weight. Suitable dyes include oily dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green B
G, oil blue BOS, oil blue # 603, 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 (CI45)
170B), malachite green (CI42000),
Methylene blue (CI52015) and the like can be mentioned.

Next, the above (A) used in the present invention,
The organic solvent (C) that dissolves (B), (D), and (E) will be described. The positive photoresist composition of the present invention is one in which the above components are dissolved in a solvent that dissolves the components and applied on a support. Examples of the solvent that can be used include ethylene dichloride, cyclohexanone, cyclopentanone, -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, lactic acid Methyl, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate,
Propyl pyruvate, N, N-dimethylformamide,
Dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable, and these solvents are used alone or in combination.

The positive photoresist composition of the present invention is applied on a substrate (eg, silicon / silicon dioxide coating) such as used in the production of precision integrated circuit devices by a suitable application method such as a spinner or a coater. By exposing through a predetermined mask, baking and developing, a good resist pattern can be obtained.

The developer for the positive photoresist composition of the present invention includes, for example, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium phosphate, sodium metasilicate and aqueous ammonia. , Ethylamine, primary amines such as n-propylamine, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, and alcoholamines such as dimethylethanolamine and triethanolamine. , Amides such as formamide and acetamide, tetramethylammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide, tetraethylammonium hydroxide, tributylmethylammonium hydroxide, Ethanol ammonium hydroxide, methyl triethanol ammonium hydroxide,
Quaternary ammonium salts such as benzylmethyldiethanolammonium hydroxide, benzyldimethylethanolammonium hydroxide, benzyltriethanolammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide; cyclic amines such as pyrrole and piperidine; There are aqueous solutions of alkalis.

When the resist of the positive photoresist composition of the present invention is used as the upper resist of a two-layer resist, the lower organic polymer film is etched by oxygen plasma using the upper resist pattern as a protective mask. The upper resist has sufficient resistance to oxygen plasma. Although the oxygen plasma resistance of the positive photoresist composition of the present invention depends on the silicon content of the upper resist, the etching apparatus, and the etching conditions, the etching selectivity (the etching rate ratio between the lower resist and the upper resist) is 10%. It can be taken as a sufficiently large value of ~ 100.

In the pattern forming method using the positive photoresist composition of the present invention, first, an organic polymer film is formed on a substrate to be processed. The organic polymer film may be various known photoresists, and examples thereof include FH series and FHi series manufactured by Fujifilm Olin Co., or OiR series manufactured by Olin Co., and PFI series manufactured by Sumitomo Chemical Co., Ltd. The formation of the organic polymer film is performed by dissolving these in an appropriate solvent and applying the resulting solution by a spin coating method, a spraying method or the like. Next, a film of the positive photoresist composition of the present invention is formed on the first layer of the organic polymer film. This is performed by dissolving the resist material in an appropriate solvent in the same manner as in the first layer, and applying the resulting solution by spin coating, spraying, or the like. The obtained two-layer resist is then subjected to a pattern forming step. As a first step, a pattern forming process is first performed on the second layer, that is, the film of the upper photoresist composition. Perform mask alignment as necessary, and irradiate high-energy radiation through this mask to make the irradiated portion of the photoresist composition soluble in an alkaline aqueous solution,
The pattern is formed by developing with an alkaline aqueous solution.

Next, as a second step, the organic polymer film is etched. This operation is performed by oxygen plasma etching using the above-mentioned resist composition film pattern as a mask to form a fine pattern having a high aspect ratio. I do. The etching of the organic polymer film by the oxygen plasma etching is exactly the same technique as the plasma ashing used when the resist film is peeled off after the etching of the substrate is completed by the conventional photoetching operation. This operation can be performed by, for example, a cylindrical plasma etching apparatus or a parallel flat slope plasma etching apparatus using oxygen as a reactive gas, that is, an etching gas. Further, the substrate is processed using this resist pattern as a mask. As a processing method, a dry etching method such as sputter etching, gas plasma etching, or ion beam etching can be used.

The etching process by the two-layer resist method including the resist film of the present invention is completed by the operation of removing the resist film. The removal of the resist layer can be carried out simply by dissolving the organic polymer material of the first layer. Since this organic polymer material is an arbitrary photoresist and has not been altered (hardened or the like) at all in the photoetching operation, an organic solvent of each known photoresist itself can be used. Or,
By a process such as plasma etching, separation can be performed without using a solvent.

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EXAMPLES Hereinafter, the present invention will be described with reference to the following synthetic examples, examples, and comparative examples. However, the present invention is not limited to the following examples.

Synthesis Example 1 (Synthesis of Resin (1)) (2-hydroxyethyl) tris (trimethylsilyl)
58.4 g of silane and 30.8 g of cyclohexanedicarboxylic anhydride were dissolved in 500 ml of THF.
-Dimethylaminopyridine (2 g) was added and reacted at 60 ° C under nitrogen for 6 hours. 34.0 g of chloromethyltrimethoxysilane was added thereto, and 19.0 g of diazabicycloundecene was added thereto. After filtering off the white precipitate, THF was distilled off to obtain a trimethoxysilane intermediate.

To 46.5 g of the above intermediate, 31.2 g of cyclohexyltrimethoxysilane was added to 200 ml of N, N-dimethylacetamide.
After adding 5 g of -dimethylaminopyridine, the mixture was reacted at 60 ° C for 3 hours and further at 140 ° C for 3 hours. After the reaction solution was returned to room temperature, it was poured into 3 L of distilled water with stirring to obtain a white powdery polymer. 200 ml of this in acetone
And the oligomer component of the polymer is separated and removed by adding distilled water with stirring, and the lower layer is distilled water 2
The precipitate was reprecipitated in L to obtain a white polymer. When the average molecular weight of this polymer was measured by GPC (polystyrene standard), the weight average molecular weight was 3900, and the content of components having a molecular weight of 1,000 or less was 3% by GPC area ratio.

The following polysiloxane was synthesized in the same manner.

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Example 1 2 g of the resin (1) as an acid-decomposable polymer component and 0.12 g of triphenylsulfonium perfluorooctanesulfonate as a compound component which generates an acid upon exposure to light
And 0.012 g of DBU, the following surfactant W-
1 was dissolved in 19.2 g of propylene glycol monomethyl ether acetate (PGMEA), and finely filtered through a 0.1 μm membrane filter. FHi-028D resist (Fujifilm Ohlin Co., Ltd., i-line resist) is coated on a silicon wafer by Canon Coater CDS-6.
Coating was carried out by using No. 50 and baked at 90 ° C. for 90 seconds to obtain a uniform film having a thickness of 0.83 μm. This is further added to 200 ° C,
After heating for 3 minutes, the film thickness became 0.71 μm. The silicon-containing resist prepared above was applied thereon, and 90
The film was baked at 90 ° C. for 90 seconds to form a film having a thickness of 0.20 μm.

The wafer thus obtained was exposed to light while changing the exposure amount and focus by loading a resolution mask on an ArF stepper. Then 120 ° C in a clean room,
After heating for 90 seconds, the film was developed with a tetramethylammonium hydroxide developer (2.38%) for 60 seconds, rinsed with distilled water and dried to obtain a pattern. Observation with a scanning electron microscope revealed that the sensitivity was 0.15 at a sensitivity of 30 mJ / cm ² .
μm lines / spaces were resolved. The rectangularity of the cross section was evaluated as A.

The rectangularity of the cross section was compared by a three-step evaluation as follows. That is, the angle between the substrate and the side wall of the resist pattern was measured, and the angle between 80 ° and 90 ° was A
Evaluated, those with 70 ° or more and less than 80 ° were evaluated as B, and those with less than 70 ° were evaluated as C. Further, the wafer was subjected to an etching treatment for 15 minutes under the conditions of a pressure of 20 mTorr and an applied power of 100 mW / cm ² using an etching gas of oxygen and a parallel plate type reactive ion etching apparatus manufactured by ULVAC. The results were observed with a scanning electron microscope. The dimensional shift of the 0.15 μm pattern is 0.005
μm.

Examples of the surfactant include W-1: Megafac F176 (Dainippon Ink Co., Ltd.)
(Fluorine) W-2: Megafac R08 (Dai Nippon Ink Co., Ltd.)
(Fluorine and silicone type) W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) W-4: Polyoxyethylene nonylphenyl ether.

Examples 2 to 12 In place of the acid-decomposable polysiloxane (a) and the acid generator (b) in Example 1, the components shown in Table 1 were used.
A positive photoresist was prepared in the same manner as in Example 1 except that the components (a) and (b) were used, and exposed, developed and etched in the same manner as in Example 1. The results are summarized in Table 2.

(Comparative Example) The following (R1) was used in place of the acid-decomposable polysiloxane in Example 1, except that
A positive photoresist was prepared in exactly the same manner as in Example 1, and exposed, developed and etched in the same manner as in Example 1. Table 3 shows the obtained performance.

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[Table 1]

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[Table 2]

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[Table 3]

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According to the present invention, in the manufacture of a semiconductor device, it is possible to obtain a positive resist composition which provides a photoresist for forming a rectangular pattern.
Further, the positive resist composition of the present invention has low edge roughness of the line pattern. Further, the dimension shift is small when transferring the pattern to the lower layer in the oxygen plasma etching step.

Claims (4)

[Claims] 1. A positive photoresist composition comprising at least an acid-decomposable polysiloxane having a structural unit represented by the following general formula (I). Embedded image In the formula (I), L ¹ represents —A ¹ —OCO—, —A ¹ —COO
-, -A ¹ -NHCO-, -A ¹ -NHCOO-, -A ^{1
-NHCONH -, - A 1 -CONH -} , - A 1 -OCO
NH- or an -A ¹ -S-. A ¹ represents an alkylene group, an arylene group, and at least one divalent linking group selected from monocyclic and bridged alicyclic structures. M ¹ represents a single bond, an alkylene group, an arylene group, or a divalent linking group having a monocyclic or bridged alicyclic structure. R '~
R ′ ″ independently represents an alkyl group, a haloalkyl group, a halogen atom, an alkoxy group, a trialkylsilyl group or a trialkylsilyloxy group. 2. The positive photoresist composition according to claim 1, wherein the acid-decomposable polysiloxane further contains a repeating structural unit represented by the following general formula (II). Embedded image In the formula (II), L ² is a single bond, -A ² -OCO-, -A ^{2
-COO -, - A 2 -NHCO -} , - A 2 -NHCOO
^{-, - A 2 -NHCONH -,} - A 2 -CONH -, - A
² -OCONH- or an -A ² -S-. A ² represents a single bond, an alkylene group or an arylene group. M ² represents an aryl group, an aralkyl group, or a monocyclic or bridged alicyclic group. 3. The positive photoresist composition according to claim 1, wherein the acid-decomposable polysiloxane further contains a repeating structural unit represented by the following general formula (III). Embedded image (A) the acid-decomposable polysiloxane according to any one of claims 1 to 3, (B) a compound which decomposes upon irradiation with actinic rays or radiation to generate an acid, (C) the (A) An organic solvent capable of dissolving) and (B) (D) an organic basic compound soluble in the organic solvent (C),
And (E) a surfactant comprising a surfactant.