JP2001174998A - Positive photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive photoresist composition having high sensitivity and high resolving power and giving a photoresist having a rectangular shape and to provide a polysiloxane less liable to cause a size shift in pattern transfer to a lower layer in an oxygen plasma etching step and capable of imparting excellent characteristics to a positive photoresist composition. SOLUTION: The positive photoresist composition contains at least an alkali- soluble polysiloxane having a structural unit of formula I, e.g. formula II and contains, in principle, the polysiloxane, a compound which is decomposed by exposure to form an acid and a phenolic compound in which phenolic hydroxyl groups contained in its molecule have been partially or wholly protected with acid decomposable groups. The composition may contain an aromatic or aliphatic carboxylic acid compound in which carboxyl groups contained in its molecule have been partially or wholly protected with acid decomposable groups.

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.

[0002]

2. Description of the Related Art As a pattern forming method for manufacturing electronic components such as a semiconductor device, a magnetic bubble memory, and an integrated circuit, a method utilizing a photoresist which is sensitive to ultraviolet light or visible light has been widely used. Have been. 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 density and integration of semiconductor devices and the like, the line width and spacing of patterns have become extremely small.
In addition, since dry etching has been adopted for etching the substrate, photoresists have been desired to have high resolution and high dry etching resistance,
At present, positive photoresists occupy the majority. In particular, among positive photoresists, sensitivity,
Because of its excellent resolution and dry etching resistance, for example, JC Strieter, Kodak Microelectronics Seminar Proceedings, p. 116 (1976) (JC Strieter, Kodak Micr)
o electronics Seminar Proceedings, 116 (197
6 years) and the like, and an alkali-developable positive photoresist based on an alkali-soluble novolak resin has become the mainstream of the current process.

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,
Problems have also arisen with various types of exposure methods as the minimum dimensions are reduced. 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 fine resist is exposed due to the proximity effect caused by backscattering of electrons. It is no longer possible to increase the height to width ratio of the pattern.

It has been found that many of these problems are eliminated by using a multilayer resist system. For multi-layer resist systems, see Solid State Technology, 74 (1981) [Solid Stat.
e Technology, 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 planarization film by O2RIE (reactive ion etching) using the inorganic intermediate layer as a mask. This method
Basically, studies were started from an early stage because conventional technologies could be used.However, the process was very complicated, or organic films, inorganic films, and organic films overlapped with those with different physical properties. Another problem is that cracks and pinholes are likely to occur in the intermediate layer.

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.

On the other hand, a polysiloxane having alkali solubility imparted to a conventional orthoquinonediazide photosensitive material,
Or a photosensitive composition combining a silicone polymer such as polysilmethylene, for example, JP-A-61-144639, JP-A-61-256347, JP-A-62-159141, and JP-A-6-159141.
2-191849, 62-220949, 62
-229136, 63-90534, 63-9
1654 and U.S. Pat. No. 4,722,881 and a photosensitive composition obtained by combining an effective amount of an onium salt with a polysiloxane / carbonate block copolymer described in JP-A-62-136638. Proposed.

However, any of these silicone polymers has a phenolic OH group or a silanol group (≡Si
-OH) is introduced to impart alkali solubility, and when alkali solubility is imparted by introduction of a phenolic OH group, the production becomes extremely difficult. There was a problem that the film was not good, or the film loss after development was large, and rectangular properties could not be obtained. Also, Japanese Patent No. 2736939 and Japanese Patent Application Laid-Open No. 9-274319
Discloses a photoresist containing a polysiloxane having in its molecule a group that can be decomposed by the action of an acid. However, these photoresists have a problem that the resolution is low, the shape is not rectangular, and the size shift is large when transferring the pattern to the lower layer in the next oxygen plasma process.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor device having a high sensitivity and a high sensitivity of 0.2 μm.
An object of the present invention is to provide a positive photoresist composition having a high resolution of not more than m and providing a photoresist having a rectangular shape. Another object of the present invention is to provide a positive photoresist composition having a small dimensional shift during pattern transfer to a lower layer in an oxygen plasma etching step when used as an upper layer resist in a two-layer resist system. . Still another object of the present invention is to provide a polysiloxane capable of imparting the above excellent properties to a positive photoresist composition.

[0011]

According to the present invention, the above-mentioned object is achieved by providing the following positive photoresist composition. (1) A positive photoresist composition comprising an alkali-soluble polysiloxane having at least a structural unit represented by the following (I):

[0012]

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L is -A-NHCO-, -A-NHCOO
-,-Represents a divalent linking group selected from A-NHCONH-. A represents an alkylene group or an arylene group. X represents a single bond or a divalent linking group. Z is

[0014]

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Represents any monovalent group represented by Y
Represents a hydrogen atom. Or, Y represents an alkyl group, an aryl group or an aralkyl group. The atomic group represented by Y may be linear, branched, or cyclic. l represents an integer of 1 to 3. m also represents an integer of 1 to 3. (2) The positive photoresist composition according to the above (1), further comprising an alkali-soluble polysiloxane containing a structural unit represented by the following formula (II).

[0016]

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X 'and Z' refer to the same range as X and Z in (1) above.

Represents a monovalent group selected from the group consisting of the groups represented by Y represents a hydrogen atom. Or, Y represents an alkyl group, an aryl group or an aralkyl group. The atomic group represented by Y may be linear, branched, or cyclic. 1 represents an integer of 1 to 3, m represents an integer of 1 to 3, and n represents an integer of 1 to 6. (3) In the above (I), L is — (CH ₂ ) ₃ —NHCO
-The positive photoresist composition as described in (2) above, wherein (4) A positive photoresist composition comprising at least the following (a), (b) and (c1). (A) The alkali-soluble polysiloxane according to any one of the above (1) to (3). (B) Compounds that decompose upon exposure to generate an acid. (C1) A phenolic compound in which a phenolic hydroxyl group contained in a molecule is partially or completely protected by a group capable of being decomposed by an acid. (5) A positive photoresist composition comprising at least the following (a), (b) and (c2). (A) The alkali-soluble polysiloxane according to any one of the above (1) to (3). (B) Compounds that decompose upon exposure to generate an acid. (C2) An aromatic or aliphatic carboxylic acid compound in which a carboxyl group contained in the molecule is partially or completely protected by a group capable of being decomposed by an acid.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The polysiloxane used in the positive photoresist composition of the present invention will be described. In the general formula (I), L represents -A-NHCO-, -A-NH
COO-,-represents at least one divalent linking group selected from A-NHCONH-. A represents an alkylene group or an arylene group. Among them, an alkylene group having 1 to 6 carbon atoms or a phenylene group is preferable, and a propylene group is more preferable. L is -A-NHCO-,
In the case of -A-NHCOO- or -A-NHCONH-, the heat resistance of the polysiloxane is increased by hydrogen bonding, whereby a high resolution and a rectangular pattern can be obtained. Here, when A is represented by a propylene group, the target polysiloxane can be obtained from an inexpensive raw material of 3-aminopropyl trialkoxysilane, and the silicon content in the polysiloxane can be maintained at a high level. preferable. X and X ′ represent a single bond or a divalent linking group. Specifically, single or two or more selected from the group consisting of a single bond, an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, and a urea group Combinations. It is preferably a single bond or an alkylene group, and more preferably a single bond or an alkylene group having 1 to 6 carbon atoms. Z and Z ′ are

[0020]

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Represents a monovalent group selected from the group consisting of the groups represented by Y is a hydrogen atom. Or, Y represents an alkyl group, an aryl group, or an aralkyl group. When Y is an atomic group, it may be linear, branched, or cyclic. Preferably, Y is a hydrogen atom or a straight chain having 1 to 6 carbon atoms,
It is a branched or cyclic alkyl group. l represents an integer of 1 to 3, and m represents an integer of 1 to 3. As a resist composition, not only the solubility in a general-purpose ester or alcohol-based organic solvent is increased, but also the compatibility between the photoacid generator and the polysiloxane is increased, and a resist composition exhibiting high resolution is provided.
The alkali-soluble polysiloxane of the present invention preferably contains the structural unit represented by the general formula (I) in an amount of 10 to 100 mol%, more preferably 30 to 100 mol%.
It is. Further, in a polysiloxane containing both the structural unit represented by the general formula (I) and the structural unit represented by the general formula (II), the total of the structural units of the formulas (I) and (II) is 20 to
The content is preferably 100 mol%, more preferably 50 to 100 mol%. The content ratio represented by (I) / (II) is preferably from 80/20 to 40/60.

In the alkali-soluble polysiloxane of the present invention, structural units of the following general formulas (III) and (IV) may be further copolymerized in order to control the solubility of the solvent and the solubility of the alkali. The content of the structural units represented by the general formulas (III) and (IV) is preferably from 10 to 70 mol%.

[0023]

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Here, W, W ¹ and W ² represent groups having neither alkali solubility nor acid decomposability. Specifically, it represents an alkyl group, an aryl group, or an aralkyl group. In the case of an alkyl group, a linear group having 1 to 10 carbon atoms, a branched group having 3 to 10 carbon atoms, and a cyclic group having 6 to 10 carbon atoms can be exemplified.
In any case, the compound may have a substituent or may not have a substituent. In the case of an aryl group, an aryl group having 6 to 10 carbon atoms can be mentioned. In the case of an aralkyl group,
An aralkyl group having 7 to 11 carbon atoms can be mentioned.
Each of the aryl group and the aralkyl group may or may not have a substituent. Preferred specific examples of these groups include methyl, ethyl, n-propyl,
i-propyl, n-butyl, i-butyl, t-butyl,
Examples thereof include n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, cyclohexyl, phenyl, naphthyl, benzyl, and naphthylmethyl. Examples of the substituent of these groups include a halogen atom, an alkoxy group having 1 to 6 carbon atoms, a phenoxy group, and a hydroxyl group. Note that W ¹ and W ² may be the same or different. The alkali-soluble polysiloxane having a structural unit represented by the general formula (I) is obtained by subjecting a carboxylic acid compound having a phenol structure and a monosubstituted trialkoxysilane having an amino group at a terminal to a DCC method or a mixed acid anhydride method. To convert the phenol structure to a trialkoxysilane structure by amide and then optionally give a monosubstituted trialkoxysilane or disubstituted dialkoxysilane to give the structural units represented by the above general formulas (II) to (IV) Is added, followed by condensation polymerization in the presence of water and an acid, or water and a base catalyst. In order to increase the yield of the reaction, a carboxylic acid compound having a phenol group in which an OH group is protected and a monosubstituted trialkoxysilane having an amino group at a terminal are converted to a phenol structure by a DCC method or a mixed acid anhydride method. The amide linkage of the trialkoxysilane structure is performed, and then the deprotection of the protecting group is followed by condensation polymerization in the presence of water and an acid, or water and a base catalyst, or the amidation is followed by water and an acid, or water. After decondensation is performed in the presence of a base catalyst, deprotection may be performed. As the protecting group for OH, t-butoxycarbonyl (BOC), acetyl, alkoxy, benzyloxycarbonyl (Z) trialkylsilyl and the like can be used. Specific examples of the structural unit of the polysiloxane of the present invention are shown below, but the present invention is not limited thereto.

[0025]

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[0031]

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[0032]

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[0033]

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The molecular weight is 2000 to 2000 as a weight average.
20000 is good. Preferably, the weight average is 4000 to 1
2000. Next, the positive photoresist composition of the present invention will be described. The positive photoresist composition of the present invention comprises: (a) the above polysiloxane; and (b) a compound capable of decomposing upon exposure to generate an acid (photoacid generator). (C1) a phenolic hydroxyl group contained in the molecule; And a phenolic compound protected by an acid-decomposable group. Protection may be partial or complete. Instead of such a phenolic compound, (c2) an aromatic or aliphatic carboxylic acid compound protected by a group capable of being decomposed by an acid may be contained. Protection may be partial or complete. (Hereinafter, (c1) and (c2) may be collectively referred to as (c).)

The photoacid generator (b) used in the present invention comprises:
A compound that generates an acid upon irradiation with actinic rays or radiation. 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 photodecolorant for dyes, and a photodiscoloration agent. Agents or known light used in micro resists (400 to 200 nm ultraviolet light,
Far ultraviolet rays, particularly preferably g-line, h-line, i-line, KrF
Excimer laser light), ArF excimer laser light, an electron beam, an X-ray, a compound generating an acid by a molecular beam or an ion beam, and a mixture thereof can be appropriately selected and used.

Other examples of the compound capable of generating an acid upon irradiation with actinic rays or radiation used in the present invention include, for example, SI Schlesinger, Photogr. Sci. En.
g., 18,387 (1974), TS Bal et al, Polymer, 21, 423
(1980) diazonium salts described in U.S. Pat.No.4,069,05
No. 5, 4,069,056, 27,992, ammonium salts described in JP-A-3-140140, etc., DC Necker et al, Macrom
olecules, 17, 2468 (1984), CS Wen et al, Teh, Pr.
oc.Conf.Rad.Curing ASIA, p.478 Tokyo, Oct (198
8), U.S. Pat.Nos. 4,069,055, 4,069,056, etc., and phosphonium salts described in JV Crivello et al, Macromorecu
les, 10 (6), 1307 (1977), Chem. & Eng. News, Nov. 28,
p.31 (1988), European Patent Nos. 104,143 and 339,049,
410,201, JP-A-2-150848, iodonium salts described in JP-A-2-29514, etc., JV Crivelloet al, Polymer
J. 17, 73 (1985), JV Crivello et al. J. Org. Ch.
em., 43, 3055 (1978), WR Watt et al, J. Polymer Sc
i., Polymer Chem.Ed., 22, 1789 (1984), JV Crive
llo et al, Polymer Bull., 14, 279 (1985), JVCriv
ello et al, Macromorecules, 14 (5), 1141 (1981), J.
V. Crivello et al, J. Polymer Sci., Polymer Chem. E
d., 17, 2877 (1979), European Patent Nos. 370,693, 161,811
Nos. 410,201, 339,049, 233,567, 297,4
No. 43, No. 297,442, U.S. Pat.Nos. 3,902,114, 4,933,
No. 377, 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 and the like, JV Crivello et al, Macromorecules, 1
0 (6), 1307 (1977), JV Crivello et al, J. Polymer
Sci., Polymer Chem.Ed., 17, 1047 (1979) and the like, CS Wen et al, Teh, Proc. Conf.
Onium salts such as arsonium salts described in Rad. Curing ASIA, p.478 Tokyo, Oct (1988), 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, and organic halogen compounds described in JP-A-63-298339, K. Meier et al, J. Rad.
g, 13 (4), 26 (1986), TP Gill et al, Inorg.
m., 19, 3007 (1980), D. Astruc, Acc. Chem. Res., 19
(12), 377 (1896), and organometallic / organic halides described in JP-A-2-14145, S. Hayase et al, J. Polymer
Sci., 25, 753 (1987), E. Reichmanis et al, J. Pholyme
r Sci., Polymer Chem. Ed., 23, 1 (1985), QQ Zhu et
al, J. Photochem., 36, 85, 39, 317 (1987), B. Amit
etal, Tetrahedron Lett., (24) 2205 (1973), DHR
Barton et al, J. Chem Soc., 3571 (1965), PM Colli
ns et al, J. Chem. Soc., Perkin I, 1695 (1975), M.R.
udinstein et al, Tetrahedron Lett., (17), 1445 (197
5), JW Walker etal 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 Collinsetal, J. Chem. Soc.,
Chem. Commun., 532 (1972), S. Hayasetet al, Macromole
cules, 18, 1799 (1985), E. Reichmanis et al, J. Elec
trochem. Soc., Solid State Sci. Technol., 130 (6),
FM Houlihan et al, Macromolcules, 21, 2001 (198
8), European Patent Nos. 0290,750, 046,083, 156,535
No. 271,851, No. 0,388,343, U.S. Pat.No. 3,901,71
No. 0, 4,181,531, JP-A-60-198538, JP-A-53-13
No. 3022, etc., a photoacid generator having an O-nitrobenzyl-type protecting group, M. TUNOOKA et al, Polymer Preprints Ja
pan, 35 (8), G. Berneret al, J. Rad. Curing, 13 (4),
WJ Mijs et al, Coating Technol., 55 (697), 45 (19
83), Akzo, H. Adachi et al, Polymer Preprints, Japa
n, 37 (3), European Patent Nos. 0199,672, 84,515, 044,1
No. 15, 618,564, No. 0101,122, U.S. Pat.No. 4,371,6
No. 05, 4,431,774, JP-A-64-18143, JP-A-2-24
No. 5756, compounds that generate sulfonic acid upon photolysis, such as iminosulfonate described in JP-A-3-140109, etc., described in JP-A-61-166544, JP-A-2-71270, etc. Disulfone compound, JP-A-3-103854, JP-A-3-103856
And the diazoketosulfone and diazodisulfone compounds described in JP-A Nos. 4-210960 and 4-210960.

Further, a group generating an acid by these lights,
Alternatively, a compound having a compound introduced into a main chain or a side chain of a polymer, for example, ME Woodhouse et al, J. Am. Che.
m. 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-63-1
Compounds described in JP-A-63452, 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 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 (PAG)
An S-triazine derivative represented by 2).

[0040]

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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
Is shown. Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0042]

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[0043]

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[0044]

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

[0046]

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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 ²⁰³ , R ²⁰⁴ and R ²⁰⁵ each independently represent a substituted or unsubstituted alkyl group or aryl group. Preferably, an aryl group having 6 to 14 carbon atoms, 1 to 8 carbon atoms
And substituted derivatives 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.

[0049] 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:

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

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

[0052]

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[0053]

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[0059]

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[0060]

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[0065]

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The onium salts represented by the general formulas (PAG3) and (PAG4) are known. W. Kn
apczyk et al, J. Mol. Am. Chem. So
c. , 91, 145 (1969); L. Mayco
k et al, J. et al. Org. Chem. , 35,25
32, (1970); Goethas et a
1, Bull. Soc. Chem. Belg. , 73,
546, (1964); M. Leicester,
J. Am. Chem. Soc. , 51, 3587 (19
29); V. Crivello et al, J. Mol.
Polym. Chem. Ed. , 18, 2677 (19
80); U.S. Patent Nos. 2,807,648 and 4,2;
No. 47,473, JP-A-53-101,331 and the like.

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

[0069]

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Where 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.

[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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In the present invention, the photoacid generator (b) is preferably an onium salt, disulfone, 4-position DNQ (diazonaphthoquinone) sulfonic acid ester, or a triazine compound.

The amount of the photoacid generator (b) used is usually in the range of 0.001 to 40% by weight based on the total weight (excluding the coating solvent) of the positive photoresist composition of the present invention. 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.

The (c1) phenolic compound in which the phenolic hydroxyl group contained in the molecule is partially or completely protected by an acid-decomposable group, or (c2) the carboxyl group contained in the molecule is: As the aromatic or aliphatic carboxylic acid compound partially or completely protected with an acid-decomposable group, for example, an aromatic compound having 2 to 7 aromatic rings and having a molecular weight of 186 to 1500, or GPC
Weight average molecular weight of 2000 to 20,000
And a compound in which 20 to 100% of the hydroxyl groups of the phenolic compound selected from the hydroxystyrene copolymers are protected by an acid-decomposable group.
The amount of the component (c) is preferably 5 to 50% by weight, more preferably 1 to 50% by weight based on the polysiloxane of the present invention.
It is 0 to 40%, particularly preferably 20 to 30%.

Specific examples of the component (c) include the following compounds.

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[0095]

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[0096]

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[0097]

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[0098]

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(R in the compounds (1) to (63) is a hydrogen atom or

[0100]

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This is a group selected from the following. However, at least two or three depending on the structure are groups other than hydrogen atoms, and each substituent R may not be the same group. )

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[0105]

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An organic basic compound can be added to the composition of the present invention. 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).

[0107]

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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. 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.

[0109]

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In the 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-
Examples include (2-aminoethyl) morpholin 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.

The positive photoresist composition of the present invention may further contain, if necessary, a phenolic OH group which promotes solubility in a surfactant, a dye, a pigment, a plasticizer, a photosensitizer and a developing solution. Compounds having two or more compounds can be contained.

Suitable surfactants include, 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.

Further, the following spectral sensitizers are added to sensitize the photoacid generator to be used in a longer wavelength region than far ultraviolet where the photoacid generator used has no absorption, thereby obtaining the chemically amplified positive resist of the present invention. Can be made sensitive to i or g rays. Examples of suitable spectral sensitizers include benzophenone, p, p'-tetramethyldiaminobenzophenone, p, p'-tetraethylethylaminobenzophenone, 2-chlorothioxanthone, anthrone, 9-ethoxyanthracene, anthracene and pyrene. , Perylene,
Phenothiazine, benzyl, acridine orange, benzoflavin, cetoflavin-T, 9,10-diphenylanthracene, 9-fluorenone, acetophenone, phenanthrene, 2-nitrofluorene, 5-nitroacenaphthene, benzoquinone, 2-chloro-4-nitro Aniline, N-acetyl-p-nitroaniline, p-nitroaniline, N-acetyl-4-nitro-1-naphthylamine, viclamide, anthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1,
2-benzanthraquinone, 3-methyl-1,3-diaza-1,9-benzanthrone, dibenzalacetone,
Examples include, but are not limited to, 1,2-naphthoquinone, 3,3'-carbonyl-bis (5,7-dimethoxycarbonylcoumarin) and coronene.

Examples of the compound having two or more phenolic hydroxyl groups that promote the solubility in a developer include polyhydroxy compounds. Preferably, the polyhydroxy compound includes phenols, resorcin, phloroglucin, phloroglucside, 2,3 , 4-trihydroxybenzophenone, 2,3,4,4′-tetrahydroxybenzophenone, α, α ′, α ″ -tris (4-hydroxyphenyl) -1,3,5-triisopropylbenzene,
Tris (4-hydroxyphenyl) methane, Tris (4
-Hydroxyphenyl) ethane, 1,1'-bis (4-
(Hydroxyphenyl) cyclohexane.

The positive photoresist composition of the present invention comprises
The above components are dissolved in a solvent that dissolves the components, and coated on a support. Examples of the solvent that can be used include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, and 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, and these solvents are used alone or in combination.

The positive photoresist composition of the present invention is applied onto 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.

Examples of the developing solution for the positive photoresist composition of the present invention include 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.

The positive photoresist composition of the present invention comprises
Basically, it is composed of the components (a) and (b) described above and the component (c). In order to further improve the film properties and heat resistance, an alkali-soluble resin other than the component (a) is added. May be. As such an alkali-soluble resin, preferably, a phenolic hydroxyl group, a carboxylic acid group,
It is a polymer having an acidic hydrogen atom having a pKa of 11 or less, such as a sulfonic acid group, an imide group, a sulfonamide group, an N-sulfonylamido group, an N-sulfonylurethane group and an active methylene group.

Preferred alkali-soluble polymers include:
Novolak phenol resins, specifically, phenol formaldehyde resins, o-cresol-formaldehyde resins, m-cresol-formaldehyde resins, p-cresol-formaldehyde resins, xylenol-formaldehyde resins, or co-condensates thereof. Further, as described in JP-A-50-125806, t-
A condensate of phenol or cresol substituted with an alkyl group having 3 to 8 carbon atoms, such as butylphenol formaldehyde resin, and formaldehyde may be used in combination. Also, a polymer having a phenolic hydroxy group-containing monomer such as N- (4-hydroxyphenyl) methacrylamide as a copolymer component, p-hydroxystyrene, o-hydroxystyrene, m-isopropenylphenol, p-isopropenylphenol Or a homo- or copolymerized polymer, or a polymer in which these polymers are partially etherified or partially esterified.

When a resist of the positive photoresist composition of the present invention is used as an 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, the organic polymer film is etched as a second step. This operation is performed by oxygen plasma etching using the above-described 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 treatment by the two-layer film 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.

[0128]

Hereinafter, Synthesis Examples, Examples and Comparative Examples will be shown.
The present invention is not limited to the following examples. <Synthesis Example 1> Synthesis of polysiloxane (1)

[0129]

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After adding 28.7 g of diphenolic acid and 10.0 g of triethylamine to 200 ml of dried N, N-dimethylacetamide, the mixture was cooled to -20 ° C.
Thereto, 13.7 g of isobutyl chloroformate was added dropwise over 2 hours. The reaction was performed at 0 ° C. for 2 hours in a dry nitrogen atmosphere.
20 g of 3-aminopropyltrimethoxysilane was dripped there over 2 hours. Thereafter, the reaction was carried out at room temperature under a dry nitrogen atmosphere for 5 hours. There dimethylaminopyridine 2
g of distilled water and 15 g of distilled water at 50 ° C. for 3 hours and then 13 g.
The reaction was performed at 0 to 140 ° C. for 12 hours. After neutralizing the reaction solution with dilute hydrochloric acid, it was poured into 3 L of distilled water with stirring to obtain a white powdery polymer. After dissolving this in 200 ml of acetone, the oligomer component of the polymer was separated and removed by adding distilled water with stirring, and the lower layer was reprecipitated in 2 L of distilled water 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 4,300, and the molecular weight was 100.
The content of the component of 0 or less was 8% in GPC area ratio. <Synthesis Example 2> Synthesis of polysiloxane (2)

[0131]

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After adding 28.7 g of diphenolic acid and 10.0 g of triethylamine to 200 ml of dried N, N-dimethylacetamide, the mixture was cooled to -20 ° C.
Thereto, 13.7 g of isobutyl chloroformate was added dropwise over 2 hours. The reaction was performed at 0 ° C. for 2 hours in a dry nitrogen atmosphere.
20 g of 3-aminopropyltrimethoxysilane was dripped there over 2 hours. Thereafter, the reaction was carried out at room temperature in a dry nitrogen atmosphere for 5 hours (this is referred to as a reaction solution A). Separately, 17.2 g of chloromethyltrimethoxysilane was added to 200 ml of dried N, N-dimethylacetamide, and then 15.2 g of 4-hydroxyphenylacetic acid, 3.0 g of potassium iodide, and DBU (1,8 -Diazabicyclo [5.4.0] -7-undecene) was added. The reaction was performed at 70 to 90 ° C. for 5 hours in a dry nitrogen atmosphere (this is referred to as a reaction liquid B). After the solution B was returned to room temperature, the above solution A was added, 2 g of dimethylaminopyridine and 15 g of distilled water were added, and the mixture was reacted at 50 ° C for 3 hours and then at 130 to 140 ° C for 12 hours. After neutralizing the reaction solution with dilute hydrochloric acid, it was poured into 3 L of distilled water with stirring to obtain a white powdery polymer. After dissolving this in 200 ml of acetone, the oligomer component of the polymer was separated and removed by adding distilled water with stirring, and the lower layer was separated with 2 L of distilled water.
The precipitate was subjected to reprecipitation 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 5300, and the molecular weight was 1
The content of the components of 000 or less was 5% in GPC area ratio. The following polysiloxane was synthesized in the same manner.

[0133]

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[0134]

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[Example 1] Polysiloxane (a) of the present invention
1.6 g of polysiloxane (1) as a component and triphenylsulfonium-2,2 as an acid generator compound (b).
4,6-triisopropylphenylsulfonate 0.1
2 g, triphenylimidazole 0.012 g and compound example (60) (where R = —CH ₂ COOC (CH ₃ )
₃ ) 0.48 g as the component (C) was dissolved in 19.2 g of propylene glycol monomethyl ether acetate,
After a small amount of Surflon S-382 was added, the mixture was microfiltered with a 0.1 μm membrane filter.

A silicon wafer was coated with FHi-028D resist (i-line resist, manufactured by Fujifilm Ohlin Co.) using a coater CDS-650 manufactured by Canon Inc.
Baking was performed at 0 ° C. for 90 seconds to obtain a uniform film having a thickness of 0.83 μm. When this was further heated at 200 ° C. for 3 minutes, the film thickness became 0.71 μm. The silicon-containing resist prepared above was applied thereonto and baked at 90 ° C. for 90 seconds to form a resist.
It was applied with a film thickness of 20 μm.

The wafer obtained in this way was manufactured by Canon K
rF excimer laser stepper FPA-3000EX
3 was loaded with a resolving power mask and exposed while changing the exposure amount and focus. Then, in a clean room at 120 ° C, 9
After heating for 0 second, 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 0.16 μm at a sensitivity of 22 mJ / cm ² .
m lines / spaces were resolved. The rectangularity of the cross section was evaluated as B.

Incidentally, 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 0.008
μm. Table 2 shows the evaluation results.

Examples 2 to 14 Instead of the alkali-soluble siloxane (a), (b) and (c) in Example 1, the polysiloxane (a) and (b) A positive photoresist was prepared in exactly the same manner as in Example 1 except for using the component (c) and the component (c), and exposed, developed and etched in the same manner as in Example 1. The obtained resist performance is summarized in Table 2.

[0140]

[Table 1]

[0141]

[Table 2]

In Table 1, the component structure column (a), parentheses and the numbers in the parentheses indicate the specific examples of each of the polysiloxanes shown below. In the (c) component structure column, parentheses and the numbers in the parentheses indicate the respective specific examples in the above specific examples of the component (c). R
Represents a protecting group for protecting a phenol and a group in the structural formula of each specific example.

[Comparative Example 1] The following polysiloxane (D-1) was used in place of the polysiloxane of Example 1, and the coating, exposure, development and etching treatments were carried out in exactly the same manner as in Example 1 except that Observation was made with a scanning electron microscope in the same manner as in Example 1. Table 3 shows the results.

[0144]

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[0145]

[Table 3]

[Comparative Example 2] The following polysiloxane (D-2) was used in place of the polysiloxane of Example 1, and the coating, exposure, development, and etching treatments were performed in exactly the same manner as in Example 1 except that Observation was made with a scanning electron microscope in the same manner as in Example 1. Table 3 shows the results.

From the results shown in Tables 1 to 3, the following is clear. The positive photoresist composition of the present invention using the polysiloxane of the present invention has high resolution,
A resist having good rectangularity and a small dimensional shift after etching is provided, and these characteristics are well balanced.
On the other hand, Comparative Example 1 not using the polysiloxane of the present invention
In the case of Comparative Example 2, the balance of the above characteristics is poor.

[0148]

According to the positive photoresist composition of the present invention using the polysiloxane of the present invention, a rectangular resist having high sensitivity and high resolution can be obtained. Furthermore, when used as an upper layer resist of a two-layer resist system, a fine pattern with a small aspect shift and a high aspect ratio can be formed when transferring a pattern to a lower layer using an oxygen-based plasma etching process.

Claims (5)

[Claims] 1. A positive photoresist composition comprising an alkali-soluble polysiloxane having a structural unit represented by the following (I): Embedded image L is -A-NHCO-, -A-NHCOO-, -A-
Represents a divalent linking group selected from NHCONH-. A
Represents a single bond, an alkylene group or an arylene group. X
Represents a single bond or a divalent linking group. Z is Represents any monovalent group represented by Y represents a hydrogen atom. Or, Y represents an alkyl group, an aryl group or an aralkyl group. The atomic group represented by Y may be linear, branched, or cyclic. l represents an integer of 1 to 3. m is also 1
Represents an integer of 3. 2. The positive photoresist composition according to claim 1, further comprising an alkali-soluble polysiloxane containing a structural unit represented by the following formula (II). Embedded image X 'and Z' refer to the same range as X and Z in claim 1 respectively. 3. In the formula (I), L is — (CH ₂ ) ₃ —
3. The positive photoresist composition according to claim 2, wherein the composition is NHCO-. 4. A positive photoresist composition comprising at least the following (a), (b) and (c1). (A) The alkali-soluble polysiloxane according to any one of claims 1 to 3. (B) Compounds that decompose upon exposure to generate an acid. (C1) A phenolic compound in which a phenolic hydroxyl group contained in a molecule is partially or completely protected by a group capable of being decomposed by an acid. 5. A positive photoresist composition comprising at least the following (a), (b) and (c2): (a) The alkali-soluble polysiloxane according to any one of claims 1 to 3. (B) Compounds that decompose upon exposure to generate an acid. (C2) An aromatic or aliphatic carboxylic acid compound in which a carboxyl group contained in the molecule is partially or completely protected by a group capable of being decomposed by an acid.