JP2001215705A - Positive photoresist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive photoresist composition having satisfactory sensitively and resolving power in the formation of a contact hole pattern in the production of a semiconductor device and generating few particles in a resist solution. SOLUTION: The positive photoresist composition contains (A) an acid generating sulfonium salt compound represented by a specified structure and (B) an acid decomposable siloxane having repeating units of a specified structure.

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 Strieta, Kodak Microelectronics Seminar Proceedings, p. 116 (1976) (JC Strieter, Kodak Micro)
electronics Seminar Proceedings, 116 (1976
) And the like, and an alkali-developing positive photoresist based on an alkali-soluble novolak resin is 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, 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.

[0006] 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.

[0008] 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 a super LSI, which requires processing of an ultra-fine pattern having a line width of half a micron or less, the wavelength used in 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.

In the manufacture of semiconductor devices, apart from the purpose of forming fine line widths, the size of holes through which metal for electrodes of semiconductor devices is passed to the semiconductor surface, that is, the form of contact holes, has been miniaturized. There is a need for a suitable positive photoresist composition. However, how to design a resist material in order to form minute contact holes has not been known at all. It has been found that a resist suitable for obtaining a fine line width as described above is not necessarily suitable for contact hole use. Further, there is room for improvement in the storage stability of the resist solution. For example, when a chemically amplified photoresist is stored in a liquid state, there are problems such as poor compatibility between the resin and the photoacid generator, generation of particles in the liquid, and deterioration of resist performance. Still existed.

[0011]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a positive photoresist composition having sufficient sensitivity and resolution in forming a contact hole pattern in the manufacture of a semiconductor device. It is another object of the present invention to provide a positive photoresist composition in which generation of particles in a resist solution is small.

[0012]

Means for Solving the Problems The present inventors have conducted intensive studies on resist compositions in a positive-type chemical amplification system and found that (A) a photoacid generator having a specific structure, and (B) a specific structural unit. It has been found that the object of the present invention can be achieved by using an acid-decomposable resin having the following formula: That is,
The above object is achieved by using a positive photoresist composition containing the following acid-decomposable resin.

(1) (A) a sulfonium salt compound represented by the general formula (PAG4) which generates an acid upon irradiation with actinic rays or radiation; (B) at least the following general formula (I)
A positive photoresist composition comprising an acid-decomposable polysiloxane having a structural unit represented by the formula:

[0014]

Embedded image

In the general formula (PAG4), Rs1 to Rs3 each independently represent an alkyl group which may have a substituent or an aryl group which may have a substituent. Also Rs1 ~
Two of Rs3 may be bonded via a respective single bond or a substituent. And Z ^- represents a counter anion. Represents

[0016]

Embedded image

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 sulfonium salt compound of (A) is
The positive photoresist composition according to the above (1), which is a compound represented by the following general formula [sI], which generates an acid upon irradiation with actinic rays or radiation.

[0019]

Embedded image

In the general formula [sI], Rs4 to Rs6 each represent a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, or a substituent. A suitable alkoxy group, an alkoxycarbonyl group which may have a substituent, an acyl group which may have a substituent, an acyloxy group which may have a substituent, a nitro group, a halogen atom, a hydroxyl group, Represents a carboxyl group. 1: 1-5 m: 0-5 n: 0-5. When l + m + 1 = 1, Rs4 has an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent Represents an optionally substituted alkoxycarbonyl group, an optionally substituted acyl group, and an optionally substituted acyloxy group. X represents R—SO ₃ , R represents an aliphatic hydrocarbon group which may have a substituent, or an aromatic hydrocarbon group which may have a substituent.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the compounds used in the present invention will be described in detail. First, (B) the acid-decomposable polysiloxane (hereinafter, also referred to as an acid-decomposable resin) of the present invention will be described. In the general formula (I), L ¹ is -A ¹ -OCO
-, -A ¹ -COO-, -A ¹ -NHCO-, -A ¹ -N
^{HCOO -, - 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. 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]

Embedded image

[0023]

Embedded image

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.

The acid-decomposable polysiloxane preferably further contains a repeating structural unit represented by the following general formulas (II) and / or (III).

[0028]

Embedded image

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.

[0030]

Embedded image

In the above A ² , the alkylene group includes a linear 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, the arylene group is o-
Specific examples include a 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 the unit represented by the general formula (I) in an amount of 10 to 100 mol%, more preferably 30 to 70 mol%. 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.

[0036]

Embedded image

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.

In the acid-decomposable polysiloxane of the present invention containing the structure of the general formula (IV) and / or the general formula (V),
The content of the structure of V) and / or the structure of the formula (V) is 70 mol% or less, preferably 65 mol% or less, more preferably 60 mol% or less in all the repeating units. 7
If it exceeds 0 mol%, the resolution will deteriorate.

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 then 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 may be 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 ''.

The method for introducing the acid-decomposable group includes 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.

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 thereto.

[0045]

Embedded image

[0046]

Embedded image

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

[0048]

Embedded image

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.

(A) Sulfonium salt compound which generates an acid upon irradiation with actinic rays or radiation (hereinafter also referred to as photoacid generator) Such a photoacid generator is represented by the general formula (PAG4) And a sulfonium salt compound that generates an acid upon irradiation with actinic rays or radiation. Here, examples of the generated acid include sulfonic acid, carboxylic acid, disulfonylimide, and N-sulfonylimide. In the present invention, the use of the sulfonium salt represented by the general formula (PAG4) together with the component (B) improves the resolution of the contact hole.

Here, in the general formula (PAG4), Rs1 to Rs
and s3 each independently represents an alkyl group which may have a substituent or an aryl group which may have a substituent. 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. Preferably it is an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthracene group, and a phenanthrene group, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a pentyl group. Group, hexyl group, heptyl group and octyl group. Preferred examples of these 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, an acyl group, an acyloxy group, a hydroxy group, a mercapto group and a halogen atom. Can be

[0052] Z ^- represents a counter anion, for example BF ₄ ^{-,
_{AsF 6 -, PF 6 -,}} SbF 6 -, SiF 6 2-, ClO 4 -,
CF ₃ SO ₃ ^- perfluoroalkane sulfonate anion such as, pentafluorobenzenesulfonic acid anion, sulfonic acid anion having aliphatic hydrocarbon group or an aromatic hydrocarbon group such as a naphthalene-1-sulfonic acid anion, anthraquinone sulfonic acid Examples include anions, sulfonic acid group-containing dyes, and alkylsulfonic acids such as methanesulfonic acid, but are not limited thereto.

Two of Rs1 to Rs3 may be bonded via a single bond or a substituent.

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

[0055]

Embedded image

[0056]

Embedded image

[0057]

Embedded image

[0058]

Embedded image

[0059]

Embedded image

[0060]

Embedded image

[0061]

Embedded image

The sulfonium salt represented by the general formula (PAG4) is described, for example, in JW Knapczyket al, J. Am. Che
m. Soc., 91, 145 (1969), AL Maycok et al, J. Or
g. Chem., 35, 2532, (1970), E. Goethas et al, Bul
l. Soc. Chem. Belg., 73, 546, (1964), HM Leices
ter, J. Ame.Chem. Soc., 51, 3587 (1929), JV Cri
vello et al, J. Polym. Chem. Ed., 18, 2677 (1980),
U.S. Pat.Nos. 2,807,648 and 4,247,473, JP 53
-101331 can be synthesized.

In the present invention, the photoacid generator represented by the above general formula [sI] is particularly preferred as the photoacid generator. This can reduce the number of particles after preparing the resist composition solution and the increase in the number of particles after storage with time from the preparation. In the general formula [sI],
Examples of the alkyl group of Rs4 to Rs6 include a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, which may have a substituent.
Pentyl group, hexyl group, heptyl group, octyl group, t
-An amyl group, a decanyl group, a dodecanyl group, a hexadecanyl group and the like having 1 to 25 carbon atoms. As the cycloalkyl group, a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, which may have a substituent,
Those having 3 to 25 carbon atoms such as cyclooctyl group, cyclododecanyl group, cyclohexadecanyl group and the like can be mentioned. The alkoxy group may have a substituent,
Methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy or t-butoxy, pentyloxy, t
-Having 1 to 2 carbon atoms such as an amyloxy group, n-hexyloxy group, n-octyloxy group, n-dodecaneoxy group, etc.
There are five.

Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, an isobutoxycarbonyl group and a sec-butoxycarbonyl which may have a substituent. 2 to 25 carbon atoms such as a group or t-butoxycarbonyl group, pentyloxycarbonyl group, t-amyloxycarbonyl group, n-hexyloxycarbonyl group, n-octyloxycarbonyl group, n-dodecaneoxycarbonyl group, etc. One. The acyl group may have a substituent and has 1 carbon atom such as a formyl group, an acetyl group, a butyryl group, a valeryl group, a hexanoyl group, an octanoyl group, a t-butylcarbonyl group, and a t-amylcarbonyl group. To 25. Examples of the acyloxy group include an acetoxy group, an ethylyloxy group, a butyryloxy group, a t-butyryloxy group, and a t which may have a substituent.
-Amylyloxy group, n-hexanecarbonyloxy group,
Examples thereof include those having 2 to 25 carbon atoms such as an n-octanecarbonyloxy group, an n-dodecanecarbonyloxy group, and an n-hexadecanecarbonyloxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

As a substituent for these groups, an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, Carboxy group,
Examples thereof include an alkoxycarbonyl group and a nitro group. When l + m + n = 1, Rs4 represents an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, or a substituent. It represents an optionally substituted alkoxycarbonyl group, an optionally substituted acyl group, and an optionally substituted acyloxy group. R4 preferably has 2 or more carbon atoms, more preferably 4 or more carbon atoms.

Among the above, alkyl groups which may have a substituent of Rs4 to Rs6 include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group and a t-group.
A butyl group, an n-pentyl group, a t-amyl group, an n-hexyl group, an n-octyl group, and a decanyl group are preferable.As the cycloalkyl group, a cyclohexyl group, a cyclooctyl group, which may have a substituent, A cyclododecanyl group is preferable, and as the alkoxy group, a methoxy group, an ethoxy group, an isopropoxy group, an n-
Butoxy group, sec-butoxy group, t-butoxy group, pentyloxy group, t-amyloxy group, n-hexyloxy group, n-octyloxy group, n-dodecaneoxy group is preferable, and the alkoxycarbonyl group is preferably a substituent. Methoxycarbonyl group, ethoxycarbonyl group, isopropoxycarbonyl group, n-butoxycarbonyl group, sec-butoxycarbonyl group, t-butoxycarbonyl group, pentyloxycarbonyl group, t-amyloxycarbonyl group, n -Hexyloxycarbonyl group, n-octyloxycarbonyl group, n-dodecaneoxycarbonyl group is preferable, and the acyl group may have a substituent, formyl group, acetyl group, butyryl group, valeryl group, hexanoyl group. , Octanoyl group, t
-Butylcarbonyl group, t-amylcarbonyl group is preferable, and the acyloxy group may have a substituent,
Acetoxy group, ethylyloxy group, butyryloxy group,
A t-butyryloxy group, a t-amylyloxy group, an n-hexanecarbonyloxy group, and an n-octanecarbonyloxy group are preferred.

The alkyl group having 5 or more carbon atoms and which may have a substituent is an n-pentyl group or a t-
Amyl, n-hexyl, n-octyl and decanyl are preferred. A cycloalkyl group having 5 or more carbon atoms, which may have a substituent, is a cyclohexyl group,
A cyclooctyl group and a cyclododecanyl group are preferred. Examples of the alkoxy group having 5 or more carbon atoms, which may have a substituent, include a pentyloxy group, a t-amyloxy group,
Hexyloxy, n-octyloxy and dodecaneoxy are preferred. An alkoxycarbonyl group having 5 or more carbon atoms, which may have a substituent, includes a pentyloxycarbonyl group, a t-amyloxycarbonyl group,
Hexyloxycarbonyl, n-octyloxycarbonyl and dodecaneoxycarbonyl are preferred. As the acyl group having 5 or more carbon atoms and which may have a substituent, a paleryl group, a hexanoyl group, an octanoyl group, and a t-amylcarbonyl group are preferable. As the acyloxy group having 5 or more carbon atoms and which may have a substituent, a t-amylyloxy group, an n-hexanecarbonyloxy group, and an n-octanecarbonyloxy group are preferable. Substituents for these groups include methoxy, ethoxy, t-butoxy, chlorine, bromine, cyano,
A hydroxyl group, a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group, and a t-amyloxycarbonyl group are preferred.

The sulfonium compound represented by the general formula [sI] used in the present invention uses a sulfonic acid having a specific structure as described above as its counter anion, X ⁻ . Examples of the aliphatic hydrocarbon group which may have a substituent of R in the counter anion include a linear or branched alkyl group having 1 to 20 carbon atoms, or a cyclic alkyl group. R may be an aromatic group which may have a substituent. As the alkyl group for R, a methyl group, which may have a substituent,
Examples thereof include those having 1 to 20 carbon atoms such as an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-octyl group, a 2-ethylhexyl group, a decyl group, and a dodecyl group. . Examples of the cyclic alkyl group include a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a cyclododecyl group, an adamantyl group, a norbornyl group, a camphor group, a tricyclodecanyl group, and a mentyl group which may have a substituent. Can be. Examples of the aromatic group include a phenyl group and a naphthyl group which may have a substituent.

Among the above, as the alkyl group which may have a substituent for R, methyl, trifluoromethyl, ethyl, pentafluoroethyl, 2,2,2
2-trifluoroethyl group, n-propyl group, n-butyl group, nonafluorobutyl group, n-pentyl group, n-hexyl group, n-octyl group, heptadecafluorooctyl group, 2-ethylhexyl group, decyl group , Dodecyl group,
Examples of the cyclic alkyl group include a cyclopentyl group, a cyclohexyl group, and a camphor group. As the aromatic group, a phenyl group, naphthyl group, pentafluorophenyl group, p-toluyl group, p-
Fluorophenyl group, p-chlorophenyl group, p-hydroxyphenyl group, p-methoxyphenyl group, dodecylphenyl group, mesityl group, triisopropylphenyl group,
4-hydroxy-1-naphthyl group, 6-hydroxy-2
-Naphthyl group.

Among the above substituents, more preferred R
Specific examples of s4 to Rs6 include a methyl group, an ethyl group,
Propyl, isopropyl, n-butyl, t-butyl, n-pentyl, t-amyl, n-hexyl, n-octyl, cyclohexyl, methoxy,
Ethoxy, isopropoxy, n-butoxy, t-
Butoxy group, pentyloxy group, t-amyloxy group, hexyloxy group, n-octyloxy group, methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, t-butoxycarbonyl group, t-amyloxycarbonyl group, hexyl Oxycarbonyl group, n-octyloxycarbonyl group, formyl group, acetyl group, butyryl group, hexanoyl group, octanoyl group, t-butylcarbonyl group, t-amylcarbonyl group, acetoxy group, ethylyloxy group, butyryloxy group, t-butyryloxy Group, t-amylyloxy group, n-hexanecarbonyloxy group, n-octanecarbonyloxy group, hydroxyl group, chlorine atom, bromine atom and nitro group.

More preferable examples of the group having 5 or more carbon atoms include n-pentyl, t-amyl, n-hexyl, n-octyl, decanyl, cyclohexyl, pentyloxy, and t-pentyl. Amyloxy group, hexyloxy group, n-octyloxy group, dodecaneoxy group, pentyloxycarbonyl group, t-amyloxycarbonyl group, hexyloxycarbonyl group, n-octyloxycarbonyl group, dodecaneoxycarbonyl group, pareryl group, hexanoyl A octanoyl group, a t-amylcarbonyl group, a t-amylyloxy group, an n-hexanecarbonyloxy group, and an n-octanecarbonyloxy group.

Specific examples of the more preferred sulfonic acid substituent R include methyl, trifluoromethyl, ethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, n-butyl, and nonafluoro. Butyl group, n
-Hexyl group, n-octyl group, heptadecafluorooctyl group, 2-ethylhexyl group, camphor group, phenyl group, naphthyl group, pentafluorophenyl group, p-toluyl group, p-fluorophenyl group, p-chlorophenyl group, p-methoxyphenyl group, dodecylphenyl group, mesityl group, triisopropylphenyl group, 4-hydroxy-1-naphthyl group and 6-hydroxy-2-naphthyl group.

The total number of carbon atoms of the generated acid is preferably 1 to 30. The number is more preferably 1 to 28, and still more preferably 1 to 25. If the total number of carbon atoms is less than 1, the pattern formation may be hindered such as a t-top shape, and if it exceeds 30, the development residue may be undesirably generated. The general formula [s
Specific examples of the compound represented by the formula [I] include the following [sI-
1] to [sI-20], but the present invention is not limited thereto. These compounds are used alone or in combination of two or more.

[0074]

Embedded image

[0075]

Embedded image

[0076]

Embedded image

Next, in the positive photoresist composition of the present invention, a photoacid which can be used together with a compound (photoacid generator) which generates an acid upon irradiation with an actinic ray or radiation represented by the general formula [sI] The generator 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,
Known light (400 to 200 nm ultraviolet light, far ultraviolet light, particularly preferably g-ray, i-ray, KrF excimer laser light, ArF excimer laser light) used for photodecolorants, photochromic agents or micro resists of dyes A compound that generates an acid by light, an electron beam, an X-ray, a molecular beam, or an ion beam and a mixture thereof can be appropriately selected and used.

Further, examples of other compounds used in the present invention which generate an acid upon irradiation with actinic rays or radiation include, for example, SI Schlesinger, Photogr. Sci. Eng.,
18, 387 (1974), TS Bal et al, Polymer, 21, 423 (1
980) and the like, U.S. Pat.No.4,069,055
No. 4,069,056, Re27,992, ammonium salt described in JP-A-3-140140, etc., DC Necker et al, Macr
omolecules, 17, 2468 (1984), CS Wen et al, Teh,
Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct (198
8), U.S. Pat.Nos. 4,069,055 and 4,069,056, phosphonium salts described in JV Crivello et al, Macromorecule
s, 10 (6), 1307 (1977), Chem. & Eng. News, Nov. 28, p.
31 (1988), EP 104,143, U.S. Patent 339,049
No. 410,201, JP-A-2-150,848, JP-A-2-296,
Iodonium salts described in No. 514, JV Crivello et a
l, Macromorecules, 10 (6), 1307 (1977), JV Crivel
lo et al, J. Polymer Sci., Polymer Chem. Ed., 17,
1047 (1979) and the like, CS Wen et a
l, Teh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, O
onium salts such as arsonium salts described in ct (1988), etc.

US Pat. No. 3,905,815, JP-B-46-4605
No., JP-A-48-36281, JP-A-55-32070, JP-A-60-2
39736, JP-A-61-169835, JP-A-61-169837, JP-A-62-58241, JP-A-62-212401, JP-A-63-70243
Organohalogen compounds described in JP-A-63-298339, K. Meier et al, J. Rad. Curing, 13 (4), 26 (198
6), TP Gill et al, Inorg. Chem., 19, 3007 (198
0), D. Astruc, Acc. Chem. Res., 19 (12), 377 (1896),
Organometallic / organic halides described in JP-A-2-14145, S. Hayase et al, J. Polymer Sci., 25, 753 (198
7), E. Reichmanis et al, J. Pholymer Sci., Polymer
Chem. Ed., 23, 1 (1985), QQ Zhu et al, J. Photoch.
em., 36, 85, 39, 317 (1987), B. Amit et al, Tetrahe
dron Lett., (24) 2205 (1973), DHR Barton et al,
J. Chem Soc., 3571 (1965), PM Collins et al, J.
Chem. Soc., PerkinI, 1695 (1975), M. Rudinstein et a
l, Tetrahedron Lett., (17), 1445 (1975), JW Walke
r et al, J. Am. Chem. Soc., 110, 7170 (1988), SC
Busman et al, J. Imaging Technol., 11 (4), 191 (198
5), HM Houlihan et al, Macormolecules, 21, 2001 (1
988), PM Collins et al, J. Chem. Soc., Chem. Com.
mun., 532 (1972); S. Hayase et al, Macromolecules, 1
8, 1799 (1985), E. Reichman et al, J. Electrochem. S
oc., Solid State Sci. Technol., 130 (6), FM Houli
han et al, Macromolcules, 21, 2001 (1988), European Patent Nos. 0290,750, 046,083, 156,535, 271,851
No. 0,388,343, U.S. Pat.Nos. 3,901,710, 4,181,5
No. 31, JP-A-60-198538, JP-A-53-133022 and the like, a photoacid generator having a 0-nitrobenzyl-type protecting group, M.
TUNOOKA etal, Polymer Preprints Japan, 35 (8), G. B
erner et 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, 618,5
No. 64, No. 0101,122, U.S. Pat.Nos. 4,371,605, 4,43
No. 1,774, JP-A-64-18143, JP-A-2-245756, JP-A-3-140109, etc., compounds which generate sulfonic acid by photodecomposition represented by iminosulfonate, etc.
No. 61-166544, disulfone compounds described in JP-A-2-71270, JP-A-3-103854, JP-A-3-103856, diazoketosulfone described in JP-A-4-210960 and the like, and diazodisulfone compounds. Can be.

Further, a group that 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 particularly effectively used are described below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PA)
An S-triazine derivative represented by G2).

[0084]

Embedded image

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.

[0086]

Embedded image

[0087]

Embedded image

[0088]

Embedded image

(2) An iodonium salt represented by the following general formula (PAG3).

[0090]

Embedded image

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.

[0092] Za ^{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:

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

[0094]

Embedded image

[0095]

Embedded image

[0096]

Embedded image

[0097]

Embedded image

[0098]

Embedded image

[0099]

Embedded image

The onium salts represented by the general formula (PAG3) are known and described, for example, in JW Knapczyk et al, J. A.
m. 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, (1964), HM Le
icester, J. Ame.Chem. Soc., 51, 3587 (1929), JV
Crivello et al, J. Polym. Chem. Ed., 18, 2677 (198
0), U.S. Pat. Nos. 2,807,648 and 4,247,473, JP-A-53-101331, and the like.

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

[0102]

Embedded image

In the formula, Ar ³ and Ar ⁴ each independently represent a substituted or unsubstituted aryl group. R ²⁰⁶ represents a substituted or unsubstituted alkyl group or aryl group. A represents a substituted or unsubstituted alkylene group, alkenylene group, or arylene group. Specific examples include the following compounds, but are not limited thereto.

[0104]

Embedded image

[0105]

Embedded image

[0106]

Embedded image

[0107]

Embedded image

[0108]

Embedded image

[0109]

Embedded image

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

[0111]

Embedded image

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).

[0115]

Embedded image

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

The amount of the photoacid generator (A) to be used 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.

The positive photoresist composition of the present invention comprises
As a coating solvent, propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate, alkyl lactates such as methyl lactate and ethyl lactate, and propylene such as propylene glycol monomethyl ether and propylene glycol monoethyl ether Ethylene glycol monoalkyl ethers such as glycol monoalkyl ethers, ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate; Butanone, γ-butyrolactone, methoxyprop Selected from alkyl alkoxypropionates such as methyl phosphate and ethyl ethoxypropionate, alkyl pyruvates such as methyl pyruvate and ethyl pyruvate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. It is applied using at least one solvent.

The positive photoresist composition of the present invention may contain an organic basic compound. As a result, the sensitivity fluctuation over time 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).

[0121]

Embedded image

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.

[0123]

Embedded image

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.

The positive photoresist composition of the present invention comprises
It is preferable to contain at least one surfactant of a fluorine-based surfactant, a silicon-based surfactant, a surfactant containing both a fluorine atom and a silicon atom, and a nonionic surfactant. Among them, a fluorine-based surfactant, a silicon-based surfactant, and a surfactant containing both a fluorine atom and a silicon atom are particularly preferable. Thereby, the density dependency is improved.

As these surfactants, for example, those described in
No. 62-36663, JP-A-61-226746, JP-A-61-226745,
JP-A-62-170950, JP-A-63-34540, JP-A-7-23016
No. 5, JP-A-8-62834, JP-A-9-54432, JP-A-9-598
The surfactant described in No. 8 can be used, and the following commercially available surfactant can be used as it is. Commercially available surfactants that can be used, for example, F-top EF301, EF3
03, (Shin-Akita Chemical Co., Ltd.), Florado FC430, 431 (Sumitomo 3M), MegaFac F171, F173, F176, F
189, R08 (Dainippon Ink Co., Ltd.), Surflon S-38
2, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.)
), Troysol S-366 (Troy Chemical Co., Ltd.)
) Or a silicon-based surfactant. In addition, polysiloxane polymer KP
-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

Specific examples of other surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, and polyoxyethylene. Ethylene octyl phenol ether, polyoxyethylene alkyl allyl ethers such as 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, Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate; Can be mentioned. The amount of the surfactant is usually 0.001% by weight to 2% by weight, preferably 0.1% by weight, based on the solid content in the composition of the present invention.
It is from 01% by weight to 1% by weight. These surfactants may be added alone or in some combination.

The positive photoresist composition of the present invention may further contain an acid-decomposable dissolution inhibiting compound, a dye,
A plasticizer, a surfactant other than the above, a photosensitizer, a compound that promotes solubility in a developer, and the like can be contained.

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.

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, 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.

[0138]

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.

In the same manner, the following polysiloxane was synthesized.

[0142]

Embedded image

Examples 1 to 16 and Comparative Examples 1 to 4 (Preparation and Evaluation of Positive Resist Composition) 2 g each of the resin shown in Table 1 synthesized in the above synthesis example, 80 mg of the photoacid generator shown in Table 1, 20 mg of an organic basic compound and 10 mg of a surfactant were blended, and each was dissolved in propylene glycol monomethyl ether acetate at a solid content of 10% by weight, and then filtered through a 0.1 μm microfilter. A resist composition was prepared. Further, as Comparative Examples 1 to 4, positive resist compositions were prepared in the same manner as in Examples 1 to 16, except that the above resin and photoacid generator were used, respectively.

As the surfactant, 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 W-5: Troysol S-366 (Troy Chemical Co., Ltd.)
Made)

Examples of the organic basic compound include: 1: DBU (1,8-diazabicyclo [5.4.0]-
7-undecene) 2: 4-DMAP (4-dimethylaminopyridine) 3: TPI (2,4,5-triphenylimidazole)

(Evaluation Test) FHi-
A 028D resist (a resist for i-line, manufactured by Fujifilm Ohlin Co., Ltd.) is applied using a coater CDS-650 manufactured by Canon, and baked at 90 ° C. for 90 seconds to form a film having a thickness of 0.83 μm.
Was obtained. When this was further heated at 200 ° C. for 3 minutes, the film thickness became 0.71 μm. The above-prepared resist solution was applied thereon, baked at 130 ° C. for 90 seconds, and applied to a thickness of 0.20 μm.

The wafer thus obtained was exposed to an ArF excimer laser stepper while changing the exposure amount and the focus by mounting a resolution mask. Then, after heating at 110 ° C. for 90 seconds in a clean room, the solution was heated to 60% with a tetramethylammonium hydroxide developer (2.38%).
After developing for 2 seconds, rinsing with distilled water and drying were performed to obtain a pattern. The resist pattern of the silicon wafer thus obtained was observed with a scanning electron microscope, and the resist was evaluated as follows. Table 1 shows the results of these evaluations.

[Sensitivity]: Sensitivity is defined as the relative exposure when the exposure amount that reproduces the contact hole size of 0.18 μm with a pitch width of 1/10 is the sensitivity and the exposure amount of the resist of Example 1 is 1.0. The amount was expressed as relative sensitivity (other resist exposure / exposure in Example 1). [Resolving power]: The resolving power of a contact hole is represented by the limit contact hole size (μm) that can be resolved with an exposure amount that reproduces a contact hole size of 0.18 μm with a pitch width of 1/10.

[Number of Particles and Increase in Number of Particles after Storage over Time]: Immediately after the preparation of the positive photoresist composition solution (coating solution) prepared as described above (initial value of particles) and at 4 ° C. for one week The number of particles in the liquid after standing (number of particles after lapse of time) was counted by a particle counter manufactured by Rion. Along with the initial particle value, (number of particles after aging)
(Particle initial value) The number of particles increased calculated was evaluated.

[0150]

[Table 1]

As shown in Table 1, the positive photoresist composition of the present invention showed excellent performance in all evaluation items.

[0152]

According to the present invention, a positive photoresist composition having improved edge roughness of a resist pattern in the manufacture of a semiconductor device can be provided. Further, it is possible to provide a positive photoresist composition which is excellent in low-temperature preservability, and in particular, has little change with time (particle increase, sensitivity fluctuation) under the condition that the temperature is lowered particularly at 4 ° C.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA03 AB16 AC04 AD03 BE07 BE10 BF02 BF30 CB43 FA17 4J002 CP051 CP091 EV296 FD146 GP03

Claims (2)

[Claims] (1) a sulfonium salt compound represented by the general formula (PAG4) which generates an acid upon irradiation with actinic rays or radiation; (B) an acid having at least a structural unit represented by the following general formula (I): A positive photoresist composition comprising a decomposable polysiloxane. Embedded image In formula (PAG4), Rs1 to Rs3 each independently represent an alkyl group which may have a substituent or an aryl group which may have a substituent. Two of Rs1 to Rs3 may be bonded via a single bond or a substituent. And Z ^- represents a counter anion. Represents 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 compound according to claim 1, wherein the sulfonium salt compound (A) is a compound represented by the following general formula [sI] which generates an acid upon irradiation with actinic rays or radiation. Positive photoresist composition. Embedded image In the general formula [sI], Rs4 to Rs6 are each a hydrogen atom,
An alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, an alkoxycarbonyl group which may have a substituent, It represents an acyl group which may have a substituent, an acyloxy group which may have a substituent, a nitro group, a halogen atom, a hydroxyl group, and a carboxyl group. 1: 1-5 m: 0-5 n: 0-5. When l + m + 1 = 1, Rs4 has an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent Represents an optionally substituted alkoxycarbonyl group, an optionally substituted acyl group, and an optionally substituted acyloxy group. X represents R—SO ₃ , R represents an aliphatic hydrocarbon group which may have a substituent, or an aromatic hydrocarbon group which may have a substituent.