JP2002023369A - Radiation sensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation sensitive composition excellent in resolution, focal depth, dimensional controllability and heat resistance, excellent in dimple resistance particularly in the formation of a hole pattern using a halftone mask and having a wide focus margin. SOLUTION: The radiation sensitive resin composition contains an alkali- insoluble or slightly alkali-soluble resin component (A) which is made alkali- soluble by the action of an acid and a compound (B) which generates the acid under light or electron beams. The component (A) contains at least one polymerization unit of formula [1] or [4] and resins contained in the component (A) contain all of polymerization units [1], [2], [3] and [4] in totality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a radiation-sensitive resin composition. More specifically, the present invention relates to an improvement in a radiation-sensitive resin composition containing a resin component which is insoluble in alkali or hardly soluble in alkali and becomes alkali-soluble by the action of an acid.
The radiation-sensitive resin composition of the present invention is excellent in pattern shape, resolution, environmental resistance, and also exhibits a sufficient dimple margin and a wide focus margin, and is particularly suitable for a positive resist for producing a semiconductor integrated circuit. It is.

[0002]

2. Description of the Related Art As the degree of integration of a semiconductor integrated circuit is generally increased four times in three years as generally known, for example, dynamic random access memory (DR)
AM) as an example, full-scale production has been started at present with a storage capacity of 64 Mbits. As a result, the demand for photolithography technology, which is indispensable for the production of integrated circuits, has been increasing year by year. For example, 64
The production of M-bit DRAMs requires lithography at the level of 0.3 μm, and it is expected that the lithography at the level of 0.18 μm will be required for 256-M DRAMs with higher integration. Along with this, the wavelength used for exposure of the radiation-sensitive resin composition is also
Mercury lamp g-line (436 nm) to i-line (365 nm),
Further, the wavelength has been shortened to KrF excimer laser light (248 nm). However, a conventional radiation-sensitive resin composition using naphthoquinonediazide as a photosensitizer has a very low transmittance for light in the far ultraviolet region such as KrF excimer laser light, resulting in low sensitivity and low resolution.

[0003] As a new radiation-sensitive resin composition which solves such a problem, a chemically amplified radiation-sensitive resin comprising a photoacid generator and a compound whose solubility in an alkaline developer is increased by an acid-catalyzed reaction is proposed. Various compositions have been proposed. Examples thereof include those containing a polymerized unit represented by the formula [1] in which an alkali-affinity group in an alkali-soluble resin is protected by an acetal or a ketal, and those represented by a formula [2] protected by a t-butoxycarbonyl group. There are those containing a polymerized unit and those containing a polymerized unit represented by the formula [3] protected with a t-butyl group, but these have insufficient resolution or insufficient pattern rectangularity. Or the environmental resistance was insufficient, or the amount of dimensional change due to aging after exposure was large.

[0004] In order to solve these problems, a radiation-sensitive resin composition containing two polymerized units among the polymerized units [1] to [3] has been proposed. Has been improved. For example, a radiation-sensitive resin composition (A) containing polymerized units [1] and [2] (for example, JP-A-9-160244, JP-A-8-123032,
1-3316420) or a radiation-sensitive resin composition (b) containing polymerized units [1] and [3] (for example, JP-A-9-160244, JP-A-5-249682 and JP-A-5-249682).
No. 1-331620), the resolution, the rectangularity of the pattern, the dimensional variability due to aging, and the like are improved.

The radiation-sensitive resin composition (C) containing the polymerized units [2] and [3] has improved sensitivity, resolution, plasma etching property and the like. By the way, in the actual semiconductor device manufacturing process, as a pattern size is miniaturized year by year, a half-tone mask is increasingly used instead of a normal binary mask in order to achieve higher resolution. In a halftone mask, a small amount of light is transmitted even in the unopened portion of the mask, so that the originally unexposed portion of the resist film is also exposed. For example, in a hole process, a film near a pattern is dissolved to cause a dimple called a resist surface roughness. The phenomenon is more likely to occur. When such a phenomenon occurs, a portion which should not be eroded during etching is also eroded, which causes a short circuit or disconnection, which is a serious problem. Furthermore, a sufficiently wide focus margin is required in consideration of the steps on the substrate and the focus reproducibility of the exposure device.

[0006]

However, the compositions (a) and (b) are insufficient in dimple resistance, and the composition (c) is insufficient in focus margin. As described above, in the conventional radiation-sensitive resin composition, it is difficult to take a sufficient focus margin when trying to suppress dimples. It is extremely difficult to achieve both excellent dimple resistance and a wide focus margin, and a radiation-sensitive resin composition that can exhibit the two performances has been long-awaited.

SUMMARY OF THE INVENTION An object of the present invention is to have a high resolution capable of coping with sub-quarter micron lithography using light in the far ultraviolet region which has solved the above-mentioned problems of the prior art, and achieve both high dimple resistance and a wide focus margin. It is to provide a radiation-sensitive resin composition capable of being used.

[0008]

Means for Solving the Problems The present inventors have made intensive studies in view of the above circumstances, and have found that a resin component which is alkali-insoluble or alkali-insoluble in a radiation-sensitive resin composition and becomes alkali-soluble by the action of an acid. As a result, it has been found that by using a polymer containing specific four types of polymerized units, it is possible to achieve both high dimple resistance and a wide focus margin, thereby completing the present invention.

That is, the gist of the present invention comprises a resin component (A) which is alkali-insoluble or hardly soluble in alkali and becomes alkali-soluble by the action of an acid, and a compound (B) which generates an acid by light or electron beam. (A) contains at least one polymerized unit represented by the following general formulas [1] to [4], and the polymerized unit [1] as a whole contained in (A) ], [2], [3]
And a radiation-sensitive resin composition characterized by containing all of [4].

[0010]

Embedded image

(In the formulas [1] to [4], R ¹ ,
R ⁵ , R ⁷ and R ⁹ are each independently a hydrogen atom,
An alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, and 7 to 1 carbon atoms
0 represents an aralkyl group or an alkoxy group having 1 to 10 carbon atoms, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, C 2-10 alkynyl group, C 7
Represents an aralkyl group having from 10 to 10 or an alkoxy group having from 1 to 10 carbon atoms, R ⁴ represents an alkyl group having from 1 to 20 carbon atoms, and R ⁶ and R ⁸ each independently represent 1 to 2 carbon atoms.
0 represents an organic residue. R ³ and R ⁴ are bonded to each other to form a ring —OR′— group (where R ′ is an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms, or an alkylene group having 2 to 20 carbon atoms). Alkynylene group may be formed)

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. (Resin component (A)) Resin component (A) used in the present invention
Is a resin containing at least one polymerized unit represented by the formulas [1] to [4], and having all of the polymerized units [1], [2], [3] and [4] as the whole resin contained in (A). Including.

[0013]

Embedded image

(In the formulas [1] to [4], R ¹ ,
R ⁵ , R ⁷ and R ⁹ are each independently a hydrogen atom,
An alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, and 7 to 1 carbon atoms
0 represents an aralkyl group or an alkoxy group having 1 to 10 carbon atoms, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, C 2-10 alkynyl group, C 7
Represents an aralkyl group having from 10 to 10 or an alkoxy group having from 1 to 10 carbon atoms, R ⁴ represents an alkyl group having from 1 to 20 carbon atoms, and R ⁶ and R ⁸ each independently represent 1 to 2 carbon atoms.
0 represents an organic residue. R ³ and R ⁴ are bonded to each other to form a ring —OR′— group (where R ′ is an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms, or an alkylene group having 2 to 20 carbon atoms). (Indicating an alkynylene group). These four types of essential polymerized units [1], [2], [3] and [4] are specifically those in which a hydroxyl group is protected by an acetal or a ketal, respectively. A polymerized unit in which the vinyl group of hydroxystyrenes has been cleaved (hereinafter, may be referred to as “polymerized unit a”), a polymerized unit in which the vinyl group of hydroxystyrenes in which the hydroxyl group is protected by an alkoxycarbonyl group (hereinafter, referred to as “polymerized unit a”) Polymerized unit b "), a polymerized unit in which a vinyl group of acrylic acid in which a carboxyl group is protected with an alkyl group is cleaved (hereinafter sometimes referred to as polymerized unit c), and hydroxystyrene Polymerized units a vinyl group of the kind have been cleaved (hereinafter sometimes referred to as "polymerized units d").

The polymer units a may be used alone or in combination of two or more. In the formula [1], R ¹ is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or It represents an alkoxy group having 1 to 10 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, more preferably a hydrogen atom or 1 to 3 carbon atoms.
Is an alkyl group. R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms,
Alkenyl group having 10 to 10 carbon atoms, alkynyl group having 2 to 10 carbon atoms, aralkyl group having 7 to 10 carbon atoms, or 1 to 1 carbon atoms
It represents 0 alkoxy group, preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ⁴ represents an alkyl group having 1 to 20 carbon atoms, preferably 1 to 1 carbon atom.
It is an alkyl group of 0. R ³ and R ⁴ may be bonded to each other to form a ring —OR′— group, in which case R ′
Represents an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms or an alkynylene group having 2 to 20 carbon atoms, preferably an alkylene group having 4 to 10 carbon atoms,
More preferably, it is an alkylene group having 4 to 5 carbon atoms.

Specific examples of the polymerized unit a include p-methoxymethoxystyrene, p-1-methoxyethoxystyrene, p-1-ethoxyethoxystyrene, p-1-ethoxyethoxy-α-methylstyrene, p-1- Ethoxyethoxy-α-ethylstyrene, p-1-ethoxyethoxy-α-n-propylstyrene, p-1-ethoxyethoxy-α-n-butylstyrene, p-1-ethoxyethoxy-α-n-pentylstyrene, p-1-ethoxyethoxy-α-n-hexylstyrene, p-1-ethoxyethoxy-α-n-decanylstyrene, p-1-ethoxy-1-methylethoxystyrene, p-1-ethoxy-1-methyl -N-propoxystyrene, p-1-ethoxy-1-methyl-n-butoxystyrene, p-1-ethoxy-1-methyl- - hexyloxy styrene, p
-1-ethoxy-1-methyl-n-decanyloxystyrene, p-1-ethoxy-1-methyl-n-undecanyloxystyrene, p-1-ethoxy-1-ethyl-n
-Undecanyloxystyrene, p-1-ethoxy-1
-N-propyl-n-undecanyloxystyrene, p
-1-ethoxy-1-n-butyl-n-undecanyloxystyrene, p-1-ethoxy-1-n-hexyl-
n-undecanyloxystyrene, p-1-ethoxy-
1-n-decanyl-n-undecanyloxystyrene,
p-1-ethoxy-1-n-propoxystyrene, p-
1-n-propoxyethoxystyrene, p-1-isopropoxyethoxystyrene, p-1-n-butoxyethoxystyrene, p-1-isobutoxyethoxystyrene, p-1-tert-butoxyethoxystyrene, p
-1-n-pentyloxyethoxystyrene, p-1-
n-hexyloxyethoxystyrene, p-1-n-decanyloxyethoxystyrene, p-1-n-pentadecanyloxyethoxystyrene, p-1-methoxy-1
-Methylethoxystyrene, p-1-cyclohexyloxyethoxystyrene, p-1-cyclopentyloxyethoxystyrene, p-1-cyclohexyloxyethoxystyrene, p-1-methoxy-1-methylethoxystyrene, p-2-tetrahydrofuranyl Oxystyrene, p-2-methyl-2-tetrahydrofuranyloxystyrene, p-2-ethyl-2-tetrahydrofuranyloxystyrene, p-2-n-propyl-2-tetrahydrofuranyloxystyrene, p-3-methyl- 2-tetrahydrofuranyloxystyrene, p-2-tetrahydropyranyloxystyrene, p-2-oxiranyloxystyrene, p-2-oxetanyloxystyrene,
p-2-oxepanyloxystyrene, p-2-oxocanyloxystyrene, p-2-oxonanyloxystyrene, p-2-oxecanyloxystyrene, p-2
-Oxacycloundecanyloxystyrene, p-2-
Oxacyclododecanyloxystyrene, p-2-oxacyclotridecanyloxystyrene, p-2-oxacyclotetradecanyloxystyrene, p-2-oxacyclopentadecanyloxystyrene, p-2-oxacyclohexa Decanyloxystyrene, o-methoxymethoxystyrene, o-1-methoxyethoxystyrene,
o-1-ethoxyethoxystyrene, o-1-ethoxyethoxy-α-methylstyrene, o-1-ethoxyethoxy-α-ethylstyrene, o-1-ethoxyethoxy-α-n-propylstyrene, o-1- Ethoxyethoxy-α-n-butylstyrene, o-1-ethoxyethoxy-α-n-pentylstyrene, o-1-ethoxyethoxy-α-n-hexylstyrene, o-1-ethoxyethoxy-α-n-deca Nylstyrene, o-1-ethoxy-1-methylethoxystyrene, o-1-ethoxy-1
-Methyl-n-propoxystyrene, o-1-ethoxy-1-methyl-n-butoxystyrene, o-1-ethoxy-1-methyl-n-hexyloxystyrene, o-1
-Ethoxy-1-methyl-n-decanyloxystyrene, o-1-ethoxy-1-methyl-n-undecanyloxystyrene, o-1-ethoxy-1-ethyl-n-
Undecanyloxystyrene, o-1-ethoxy-1-
n-propyl-n-undecanyloxystyrene, o-
1-ethoxy-1-n-butyl-n-undecanyloxystyrene, o-1-ethoxy-1-n-hexyl-n
-Undecanyloxystyrene, o-1-ethoxy-1
-N-decanyl-n-undecanyloxystyrene, o
-1-ethoxy-1-n-propoxystyrene, o-1
-N-propoxyethoxystyrene, o-1-isopropoxyethoxystyrene, o-1-n-butoxyethoxystyrene, o-1-isobutoxyethoxystyrene,
o-1-tert-butoxyethoxystyrene, o-1
-N-pentyloxyethoxystyrene, o-1-n-
Hexyloxyethoxystyrene, o-1-n-decanyloxyethoxystyrene, o-1-n-pentadecanyloxyethoxystyrene, o-1-methoxy-1-methylethoxystyrene, o-1-cyclohexyloxyethoxystyrene , O-1-cyclopentyloxyethoxystyrene, o-1-cyclohexyloxyethoxystyrene, o-1-methoxy-1-methylethoxystyrene, o-2-tetrahydrofuranyloxystyrene,
o-2-methyl-2-tetrahydrofuranyloxystyrene, o-2-ethyl-2-tetrahydrofuranyloxystyrene, o-2-n-propyl-2-tetrahydrofuranyloxystyrene, o-3-methyl-2-tetrahydrofuran Nyloxystyrene, o-2-tetrahydropyranyloxystyrene, o-2-oxiranyloxystyrene, o-2-oxetanyloxystyrene, o-
2-oxepanyloxystyrene, o-2-oxocanyloxystyrene, o-2-oxonanyloxystyrene, o-2-oxecanyloxystyrene, o-2-oxacycloundecanyloxystyrene, o -2-oxacyclododecanyloxystyrene, o-2-oxacyclotridecanyloxystyrene, o-2-oxacyclotetradecanyloxystyrene, o-2-oxacyclopentadecanyloxystyrene, o-2- Oxacyclohexadecanyloxystyrene, m-methoxymethoxystyrene, m-1-methoxyethoxystyrene, m-
1-ethoxyethoxystyrene, m-1-ethoxyethoxy-α-methylstyrene, m-1-ethoxyethoxy-α-ethylstyrene, m-1-ethoxyethoxy-α
-N-propylstyrene, m-1-ethoxyethoxy-
α-n-butylstyrene, m-1-ethoxyethoxy-
α-n-pentylstyrene, m-1-ethoxyethoxy-α-n-hexylstyrene, m-1-ethoxyethoxy-α-n-decanylstyrene, m-1-ethoxy-1
-Methylethoxystyrene, m-1-ethoxy-1-methyl-n-propoxystyrene, m-1-ethoxy-1
-Methyl-n-butoxystyrene, m-1-ethoxy-
1-methyl-n-hexyloxystyrene, m-1-ethoxy-1-methyl-n-decanyloxystyrene, m
-1-ethoxy-1-methyl-n-undecanyloxystyrene, m-1-ethoxy-1-ethyl-n-undecanyloxystyrene, m-1-ethoxy-1-n-propyl-n-un Decanyloxystyrene, m-1-ethoxy-1-n-butyl-n-undecanyloxystyrene, m-1-ethoxy-1-n-hexyl-n-undecanyloxystyrene, m-1-ethoxy -1-n-
Decanyl-n-undecanyloxystyrene, m-1-
Ethoxy-1-n-propoxystyrene, m-1-n-
Propoxyethoxystyrene, m-1-isopropoxyethoxystyrene, m-1-n-butoxyethoxystyrene, m-1-isobutoxyethoxystyrene, m-1
-Tert-butoxyethoxystyrene, m-1-n-
Pentyloxyethoxystyrene, m-1-n-hexyloxyethoxystyrene, m-1-n-decanyloxyethoxystyrene, m-1-n-pentadecanyloxyethoxystyrene, m-1-methoxy-1-methyl Ethoxystyrene, m-1-cyclohexyloxyethoxystyrene, m-1-cyclopentyloxyethoxystyrene, m-1-cyclohexyloxyethoxystyrene, m-1-methoxy-1-methylethoxystyrene,
m-2-tetrahydrofuranyloxystyrene, m-2
-Methyl-2-tetrahydrofuranyloxystyrene,
m-2-ethyl-2-tetrahydrofuranyloxystyrene, m-2-n-propyl-2-tetrahydrofuranyloxystyrene, m-3-methyl-2-tetrahydrofuranyloxystyrene, m-2-tetrahydropyranyloxystyrene M-2-oxiranyloxystyrene, m-2-oxetanyloxystyrene, m-2-oxepanyloxystyrene, m-2-oxocanyloxystyrene, m-2-oxonanyloxystyrene, m
-2-oxecanyloxystyrene, m-2-oxacycloundecanyloxystyrene, m-2-oxacyclododecanyloxystyrene, m-2-oxacyclotridecanyloxystyrene, m-2-oxacyclo Polymerized units in which a vinyl group is cleaved, such as tetradecanyloxystyrene, m-2-oxacyclopentadecanyloxystyrene, and m-2-oxacyclohexadecanyloxystyrene, are exemplified. Particularly, p-1-ethoxyethoxy is preferred. Styrene, p-1-isopropoxyethoxystyrene, p
-1-n-propoxyethoxystyrene, p-1-methoxyethoxystyrene, p-1-n-butoxyethoxystyrene, p-1-cyclohexyloxyethoxystyrene, p-2-tetrahydrofuranyloxystyrene,
It is preferably a polymerized unit in which the vinyl group of p-2-tetrahydropyranyloxystyrene has been cleaved.

The molar ratio of the polymer units a to all polymer units in the resin is usually 10 to 50 mol%,
Preferably it is 10 to 45 mol%, and more preferably 15 to 40 mol%.
Preferably it is mol%. If the molar ratio of the polymerized unit a to all the polymerized units in the resin is less than 10%, the resolution and the residual film property will be reduced, and if it is more than 50%, the sensitivity will be lowered or the substrate adhesion will be deteriorated. There is.

The polymer units b may be used alone or in combination of two or more. In the formula [2], R ⁵ is a hydrogen atom and has 1 carbon atom.
An alkyl group of 10 to 10, an alkenyl group having 2 to 10 carbon atoms,
It represents an alkynyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and is preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Specific examples include a hydrogen atom, a methyl group,
Ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, s-butyl group, n-hexyl group,
Examples thereof include an n-decanyl group, and more preferably a hydrogen atom or a methyl group.

R ⁶ represents an organic residue having 1 to 20 carbon atoms.
Specific examples of R ⁶ include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, s-butyl group, i-butyl group, t-butyl group, n-pentyl group, and n
-Hexyl group, n-decanyl group, n-pentadecanyl group, n-icosanyl group, 1,1-dimethyl-n-propyl group, 1,1-dimethyl-n-butyl group, 1,1-dimethyl-n-pentyl Group, 1,1-dimethyl-n-hexyl group, 1,1-dimethyl-n-decanyl group, 1,1-dimethyl-n-pentadecanyl group, 1,1-dimethyl-n
-Octadecanyl group, 1-methyl-1-ethyl-n-propyl group, 1-methyl-1-ethyl-n-butyl group, 1
-Methyl-1-ethyl-n-pentyl group, 1-methyl-
1-ethyl-n-hexyl group, 1-methyl-1-ethyl-n-decanyl group, 1-methyl-1-ethyl-n-heptadecanyl group, 1,1-diethyl-n-propyl group,
1,1-diethyl-n-butyl group, 1,1-diethyl-
n-pentyl group, 1,1-diethyl-n-hexyl group,
1,1-diethyl-n-decanyl group, 1,1-diethyl-n-hexadecanyl group, 1-methyl-1-phenylethyl group, menthyl group, 2-isobornyl group, 1-adamantyl group, 1- (2- Methyl) adamantyl group, 1-
(3-methyl) adamantyl group, 1- (3-ethyl) adamantyl group, 1- (3-propyl) adamantyl group and the like. Preferably, R ⁶ is a tertiary alkyl group having 4 to 20 carbon atoms. Among them, t-butyl group, 1,
1-dimethylpropyl group, 1,1-dimethylbutyl group,
A 1-methyl-1-ethyl-n-propyl group and an adamantyl group are particularly preferred.

The molar ratio of the polymer units b to all polymer units in the resin is 0.5 to 20 mol%, preferably 1 to 15 mol%, more preferably 1 to 10 mol%.
It is preferred that When the molar ratio of the polymerized unit b to all the polymerized units in the resin is less than 0.5%, the dimple margin decreases, and when it exceeds 20% by mole, the focus margin may decrease or the pattern shape may deteriorate. .

The polymer units c may be used alone or in combination of two or more. In the formula [3], R ⁷ is a hydrogen atom and has 1 carbon atom.
An alkyl group of 10 to 10, an alkenyl group having 2 to 10 carbon atoms,
An alkynyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms,
It is preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Specific examples thereof include a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, an n-hexyl group, and n
And a hydrogen atom or a methyl group.

R ⁸ represents an organic residue having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 20 carbon atoms or a substituted alkyl group. Examples of the alkyl group include:
Methyl group, ethyl group, n-propyl group, n-butyl group,
n-pentyl group, n-hexyl group, n-decanyl group, n
Linear alkyl groups such as -pentadecanyl group, n-icosanyl group, i-propyl group, i-butyl group, s-butyl group, t-butyl group, 1,1-dimethyl-n-propyl group, 1,1 -Dimethyl-n-butyl group, 1,1-dimethyl-n-pentyl group, 1,1-dimethyl-n-hexyl group, 1,1-dimethyl-n-decanyl group, 1,1-dimethyl-n-pentadecanyl Group, 1,1-dimethyl-n-
Octadecanyl group, 1-methyl-1-ethyl-n-propyl group, 1-methyl-1-ethyl-n-butyl group, 1-
Methyl-1-ethyl-n-pentyl group, 1-methyl-1
-Ethyl-n-hexyl group, 1-methyl-1-ethyl-
n-decanyl group, 1-methyl-1-ethyl-n-heptadecanyl group, 1,1-diethyl-n-propyl group, 1,
1-diethyl-n-butyl group, 1,1-diethyl-n-
Pentyl group, 1,1-diethyl-n-hexyl group, 1,
1-diethyl-n-decanyl group, 1,1-diethyl-n
Alicyclic alkyl groups such as a branched alkyl group such as -hexadecanyl group, 1-adamantyl group and 2-norbornyl group; and examples of the substituted alkyl group include a methoxymethyl group, a 1-methoxyethyl group and a 1-methoxyethyl group. -Ethoxyethyl group, 1-isopropoxyethyl group, 1-n-propoxyethyl group, 1-n-butoxyethyl group, 1-cyclohexyloxyethyl group, 2-tetrahydrofuranyl group, 2
-Alkoxy-substituted alkyl such as tetrahydropyranyl group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, n-propoxycarbonylmethyl group, i-propoxycarbonylmethyl group, n-butoxycarbonylmethyl group, i-butoxycarbonylmethyl group, s -Butoxycarbonylmethyl group, t-butoxycarbonylmethyl group, (1,1-dimethyl-n-propoxy) carbonylmethyl group, (1,1-dimethyl-n-butoxy) carbonylmethyl group, 1-adamantyloxycarbonylmethyl group A 2-isobornyloxycarbonylmethyl group,
2- (t-butoxycarbonyl) ethyl group, 1- (t-
Butoxycarbonyl-substituted alkyl groups such as a (butoxycarbonyl group) ethyl group, a 1- (t-butoxycarbonyl) -1-methylethyl group, and a 2- (t-butoxycarbonyl) propyl group.

More preferably, R ⁸ has 4 to 2 carbon atoms.
0 is a branched or alicyclic tertiary alkyl group, and among them, a t-butyl group, 1,1-dimethyl-n
-Propyl group, 1,1-dimethyl-n-butyl group, 1,
1-dimethyl-n-pentyl group, 1,1-dimethyl-n
-Hexyl group, 1,1-dimethyl-n-decanyl group,
1,1-dimethyl-n-pentadecanyl group, 1,1-dimethyl-n-octadecanyl group, 1-methyl-1-ethyl-n-propyl group, 1-methyl-1-ethyl-n-butyl group, 1- Methyl-1-ethyl-n-pentyl group, 1
-Methyl-1-ethyl-n-hexyl group, 1-methyl-
1-ethyl-n-decanyl group, 1-methyl-1-ethyl-n-heptadecanyl group, 1,1-diethyl-n-propyl group, 1,1-diethyl-n-butyl group, 1,1-diethyl- n-pentyl group, 1,1-diethyl-n-hexyl group, 1,1-diethyl-n-decanyl group, 1,1-
Particularly preferred are a diethyl-n-hexadecanyl group and a 1-adamantyl group.

The molar ratio of the polymerized unit c to all the polymerized units in the resin is 0.5 to 20% by mole, preferably 0.5 to 15% by mole, and more preferably 0.5 to 1% by mole.
It is preferably 0 mol%. The molar ratio of the polymerized unit c to all the polymerized units in the resin is 0.5 mol%.
If the ratio is less than 20%, the dimple margin may be reduced or the pattern shape may be deteriorated. If the ratio is more than 20 mol%, there is a concern that the pattern size may change with time or the pattern shape may be more dependent on the substrate.

The polymerization unit d is used alone or in combination of two or more.
Can be In the general formula [4], R ⁹Is a hydrogen atom, carbon
Alkyl group having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms
Group, alkynyl group having 2 to 10 carbon atoms, 7 to 10 carbon atoms
Represents an aralkyl group or an alkoxy group having 1 to 10 carbon atoms.
And preferably a hydrogen atom or an alkyl having 1 to 10 carbon atoms
Group. Specific examples include a hydrogen atom, a methyl group,
Ethyl group, n-propyl group, i-propyl group, n-butyl
Group, i-butyl group, s-butyl group, n-hexyl group,
n-decanyl group and the like, more preferably hydrogen
Atom or methyl group.

Specific examples of the polymerized unit d include o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (o-hydroxyphenyl) propylene, 2- (m-hydroxyphenyl) propylene,
Examples thereof include those in which the vinyl group of hydroxystyrene such as 2- (p-hydroxyphenyl) propylene is cleaved, but are not limited thereto. Preferably, those in which the vinyl group of p-hydroxystyrene is cleaved. Is used.

The molar ratio of the polymerized unit d to all polymerized units in the resin is from 40 to 85% by mole, preferably from 40 to 80% by mole, and more preferably from 60 to 80% by mole. When the molar ratio of the polymerized unit d to all the polymerized units in the resin is less than 40% by mole, the adhesion of the pattern to the substrate is reduced, and 85% by mole.
If it exceeds, the residual film property may be reduced.

In the resin used in the present invention, the four components of the polymerized units a to d may all be present in the same molecular chain, or may be present in separate molecular chains. In the latter case, the polymerization unit d is preferably contained in all copolymers. When the latter is specifically described, a copolymer containing a polymerized unit a and a polymerized unit d, and a mixture of a copolymer containing a polymerized unit b, a polymerized unit c and a polymerized unit d, containing a polymerized unit a and a polymerized unit d A copolymer, a mixture of a copolymer containing a polymer unit a, a polymer unit b, a polymer unit c and a polymer unit d, a copolymer containing a polymer unit b and a polymer unit d,
A mixture of a copolymer containing a polymer unit a, a polymer unit c and a polymer unit d, a copolymer containing a polymer unit b and a polymer unit d, and a polymer unit a, a polymer unit b, a polymer unit c and a polymer unit d Mixture of copolymers, polymerized units c and d
And a mixture of a copolymer containing a polymerization unit a, a polymerization unit b and a polymerization unit d, a copolymer containing a polymerization unit c and a polymerization unit d, a polymerization unit a, a polymerization unit b, and a polymerization unit a mixture of a copolymer containing c and a polymerization unit d, a polymerization unit a, a copolymer containing a polymerization unit b and a polymerization unit d, and a mixture of a polymerization unit containing a polymerization unit a, a polymerization unit c and a polymerization unit d, A mixture of the copolymer containing the polymerization unit a, the polymerization unit b and the polymerization unit d, and the copolymer containing the polymerization unit a, the polymerization unit b, the polymerization unit c and the polymerization unit d, the polymerization unit b, the polymerization unit c, and the polymerization A copolymer containing the unit d, a mixture of the polymer unit a, the polymer unit b and the copolymer containing the polymer unit d, a polymer unit b, a copolymer containing the polymer unit c and the polymer unit d,
A mixture of a copolymer containing a polymerized unit a, a polymerized unit b, a polymerized unit c and a polymerized unit d, a copolymer containing a polymerized unit a, a polymerized unit c and a polymerized unit d, and a polymerized unit b, a polymerized unit c and a polymerized A mixture of a copolymer containing units d, a copolymer containing polymerization units a, c, and d, and a mixture of copolymers containing polymerization units a, b, c, and d Is mentioned.

Of these, polymerized units a, b and d
And a mixture of a copolymer containing the polymer units c and d are preferred. In this case, the ratio of each polymerized unit in and is arbitrary.
And d are 10 to 50 mol%, 1 to 10 mol% and 50 to 80 mol% with respect to the total polymerized units, respectively.
Mol%, preferably in which c and d
And the molar ratio with respect to all the polymerized units is 1
It is preferably 0 to 50 mol% and 50 to 80 mol%.

In particular, c is 10 to 30 mol%
Is more preferable, and in this case, other polymerized units such as styrene may be contained. The resin component used in the present invention has the property of being alkali-insoluble or hardly soluble in alkali and becoming alkali-soluble by the action of an acid,
The term “alkali-insoluble” as used herein means that the dissolution rate of a resist film under general developing conditions is 500 Å / min or less, and the term “poorly soluble in alkali” means that when a resist film is developed under general developing conditions. The alkali-soluble means that the thickness of the resist pattern after development is 50% or more of that before development, and that the film is completely dissolved when the resist film is developed under general developing conditions. means. The general development conditions are as follows:
Using an alkaline aqueous solution of 9 or more, the development temperature range is 10 to 40 ° C., and the development time (contact time with the solution) is 15 to 300 seconds. From these development conditions, the optimum pH, development temperature, and development time for the resist film can be selected.

The structural units of the resin used in the present invention include, in addition to the above-mentioned polymerized unit a, polymerized unit b, polymerized unit c and polymerized unit d, for the purpose of improving the heat resistance and etching resistance of the resist. As long as the performance of the resist is not impaired, other polymerized units usually used for a resist composition can be used. Specific examples of other polymerized units include styrene, α-methylstyrene, pt-butylstyrene, m
-T-butyl styrene, α-methyl-pt-butyl styrene, α-methyl-mt-butyl styrene and the like in which the vinyl group of styrene is cleaved, maleic anhydride, maleimide, N-methylmaleimide, etc. Maleic acids having a vinyl group cleaved, pt-butoxycarbonylmethyloxystyrene, pt-butoxycarbonylmethyloxy-α-methylstyrene, pt-butoxystyrene, mt-butoxystyrene, α- Methyl-pt-
Butoxystyrene, alkoxystyrenes such as α-methyl-mt-butoxystyrene in which the vinyl group has been cleaved, acrylic acid, methacrylic acid, methoxycarbonyl acrylate, ethoxycarbonyl acrylate, n-propoxycarbonyl acrylate, Such as acrylic acid-i-propoxycarbonyl, acrylic acid-n-butoxycarbonyl, acrylic acid-i-butoxycarbonyl, acrylic acid-s-butoxycarbonyl, acrylic acid-t-butoxycarbonyl, acrylic acid-1-adamantyloxycarbonyl, etc. Acrylic acids in which the vinyl group has been cleaved are listed. Of these, preferred are styrene and pt
-Butylstyrene and pt-butoxystyrene in which the vinyl group has been cleaved, and styrene is more preferred.

When the above-mentioned other polymer units are used, the molar ratio of the other polymer units to all polymer units in the resin is 0.5 to 30 mol%, preferably 0.5 to 30 mol%.
To 20 mol%, more preferably 0.5 to 15 mol%. If the molar ratio of the other polymerization units exceeds 30 mol%, the resolution and sensitivity may be reduced. The resin containing the polymerized unit a or b may be obtained by protecting the hydroxyl group of the resin containing the polymerized unit d by a known reaction, or may be obtained by polymerizing a corresponding vinyl monomer. The resin containing the polymerized unit d may be obtained by polymerizing the hydroxystyrenes, or by deprotecting the hydroxystyrenes obtained by polymerizing the hydroxystyrenes. Similarly, the copolymer resin of the polymerized unit d and the polymerized unit c or another polymerized unit may be obtained by copolymerizing the hydroxystyrenes with the polymerized units, or may be obtained by protecting the hydroxystyrenes of the hydroxystyrenes with the hydroxystyrenes. After copolymerizing the polymerized units, the polymer may be deprotected.

In the above-mentioned polymerization or copolymerization, various methods known in the art, for example, radical polymerization, cationic polymerization, anionic polymerization, living anionic polymerization and the like can be selected. Further, the copolymer of the polymer units c and d may be any of a random copolymer, a block copolymer and a graft copolymer. The molecular weight of the resin is 4,0 in terms of polystyrene equivalent weight average molecular weight (GPC measurement).
00 to 100,000, preferably 6,000 to
40,000, and the degree of dispersion (weight average molecular weight / mass average molecular weight) is preferably less than 2.5. When the weight average molecular weight of the resin is lower than 4,000, the heat resistance of the resist may be lowered, and
If it is higher than this, the solubility in an alkali developing solution tends to be low and the sensitivity tends to be low.

As long as the resin satisfies the conditions described above, two or more resins having different polymerization ratios may be mixed, or two or more resins containing different polymerization units may be mixed. (Photoacid generator (B)) As the compound (B) that generates an acid by radiation such as light or an electron beam, any compound that generates an acid by light or an electron beam used for exposure can be used. Specifically, for example, tris (trichloromethyl) -s-triazine, tris (tribromomethyl) -s-triazine, tris (dibromomethyl) -s-triazine, 2,4-bis (tribromo Halogen-containing s-triazine derivatives such as methyl) -6-p-methoxyphenyl-s-triazine, 1,2,3,4
-Halogen-substituted paraffinic hydrocarbons such as tetrabromobutane, 1,1,2,2-tetrabromoethane, carbon tetrabromide, iodoform, and halogen-substituted cycloparaffins such as hexabromocyclohexane, hexachlorocyclohexane, and hexabromocyclododecane Hydrocarbons, halogen-containing benzene derivatives such as bis (trichloromethyl) benzene, bis (tribromomethyl) benzene, halogen-containing sulfone compounds such as tribromomethylphenylsulfone, trichloromethylphenylsulfone, 2,3-dibromosulfolane, tris ( Halogen-containing isocyanurate derivatives such as 2,3-dibromopropyl) isocyanurate, triphenylsulfonium chloride, triphenylsulfonium methanesulfonate, and triphenylsulfonium trichloride Sulfonium such as fluoromethanesulfonate, triphenylsulfonium perfluorobutanesulfonate, triphenylsulfonium camphorsulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluoroarsenate, and triphenylsulfonium hexafluorophosphonate Iodonium salts such as salts, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium p-toluenesulfonate, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluoroarsenate, diphenyliodonium hexafluorophosphonate, methyl p-toluenesulfonate, p-toluenesulfonate Ethyl acid, butyl p-toluenesulfonate, phenyl p-toluenesulfonate, 1,2,3-tri (p-toluenesulfonyloxy) benzene, p-toluenesulfonic acid benzoin ester, methyl methanesulfonate, methanesulfonic acid Ethyl, butyl methanesulfonate, 1,2,3-
Tri (methanesulfonyloxy) benzene, phenyl methanesulfonate, benzoin methanesulfonate, methyl trifluoromethanesulfonate, ethyl trifluoromethanesulfonate, butyl trifluoromethanesulfonate, 1,2,3-tri (trifluoromethanesulfonyloxy) Sulfonates such as benzene, phenyl trifluoromethanesulfonate and benzoin trifluoromethanesulfonate; o-nitrobenzylsulfonates such as o-nitrobenzyl-p-toluenesulfonate; N, N'-di (phenylsulfonyl) ) Sulfone hydrazides such as hydrazide, disulfones such as diphenyldisulfone, bis (phenylsulfonyl) methane, bis (p-methoxyphenylsulfonyl) methane, bis ( - tolyl) methane,
Bis (2,6-dimethylphenylsulfonyl) methane,
Bissulfonylmethanes such as bis (cyclohexylsulfonyl) methane, phenylsulfonyl (cyclohexylsulfonyl) methane, p-methoxysulfonyl (cyclohexylsulfonyl) methane, bis (cyclohexylsulfonyl) diazomethane, cyclohexylsulfonylethylsulfonyldiazomethane, bis (iso-propylsulfonyl) ) Diazomethane, bis (tert-butylsulfonyl) diazomethane, bis (sec-butylsulfonyl) diazomethane, tert-butylsulfonylmethylsulfonyldiazomethane, tert-butylsulfonylcyclohexylsulfonyldiazomethane, bis (cyclopentylsulfonyl) diazomethane, cyclopentylsulfonyl-tert-butyl Sulfonyldiazomethane, bis (iso- Mirusuruhoniru) diazomethane,
Cyclohexylsulfonyl (2-methoxyphenylsulfonyl) diazomethane, cyclohexylsulfonyl (3
-Methoxyphenylsulfonyl) diazomethane, cyclohexylsulfonyl (4-methoxyphenylsulfonyl) diazomethane, cyclopentylsulfonyl (2-methoxyphenylsulfonyl) diazomethane, cyclopentylsulfonyl (3-methoxyphenylsulfonyl) diazomethane, cyclopentylsulfonyl (4-methoxyphenylsulfonyl) diazomethane Cyclohexylsulfonyl (2-fluorophenylsulfonyl) diazomethane, cyclopentylsulfonyl (2-fluorophenylsulfonyl) diazomethane, cyclohexylsulfonyl (4-fluorophenylsulfonyl) diazomethane,
Cyclopentylsulfonyl (4-fluorophenylsulfonyl) diazomethane, cyclohexylsulfonyl (4
-Chlorophenylsulfonyl) diazomethane, cyclopentylsulfonyl (4-chlorophenylsulfonyl) diazomethane, cyclohexylsulfonyl (3-trifluoromethylsulfonyl) diazomethane, cyclopentylsulfonyl (3-trifluoromethylsulfonyl) diazomethane, cyclohexylsulfonyl (4-trifluoromethoxysulfonyl) Diazomethane, cyclopentylsulfonyl (4-trifluoromethoxysulfonyl) diazomethane, cyclohexylsulfonyl (1,3,5-
Trimethylphenylsulfonyl) diazomethane, cyclohexylsulfonyl (2,3,4-trimethylphenylsulfonyl) diazomethane, cyclohexylsulfonyl (1,3,5-triethylphenylsulfonyl) diazomethane, cyclohexylsulfonyl (2,3,4-triethylphenylsulfonyl) diazomethane Cyclopentylsulfonyl (1,3,5-trimethylphenylsulfonyl) diazomethane, cyclopentylsulfonyl (2,3,4-trimethylphenylsulfonyl) diazomethane, o-toluenesulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, m- Toluenesulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, p-toluenesulfonyl (2,4,
6-trimethylphenylsulfonyl) diazomethane, 2
-Methoxyphenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 3-methoxyphenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 4-methoxyphenylsulfonyl (2,4,6-trimethylphenylsulfonyl) ) Diazomethane, 2-chlorophenylsulfonyl (2,4,
6-trimethylphenylsulfonyl) diazomethane, 3
-Chlorophenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 4-chlorophenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 2-fluorophenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane , 3-fluorophenylsulfonyl (2,4,6
-Trimethylphenylsulfonyl) diazomethane, 4-
Fluorophenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 3-trifluoromethylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 4-trifluoromethylsulfonyl (2,4,6-trimethylphenyl) Sulfonyl)
Diazomethane, 2,3-dimethylphenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, 2,4-dimethylphenylsulfonyl (2,
4,6-trimethylphenylsulfonyl) diazomethane, 2,5-dimethylphenylsulfonyl (2,4,6
-Trimethylphenylsulfonyl) diazomethane, 2,
6-dimethylphenylsulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, bis (2
4,6-trimethylphenylsulfonyl) diazomethane, benzenesulfonyl (2,4,6-trimethylphenylsulfonyl) diazomethane, o-toluenesulfonyl (2,3,6-trimethylphenylsulfonyl) diazomethane, p-toluenesulfonyl (2,3 , 6-Trimethylphenylsulfonyl) diazomethane, 2-methoxyphenylsulfonyl (2,3,6-trimethylphenylsulfonyl) diazomethane, 4-methoxyphenylsulfonyl (2,3,6-trimethylphenylsulfonyl) diazomethane, 4,6-dimethyl -2-hydroxymethylphenylsulfonyl (o-toluenesulfonyl)
Diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (p-toluenesulfonyl) diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (2-methoxyphenylsulfonyl)
Diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (4-methoxyphenylsulfonyl) diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (2-fluorophenylsulfonyl) diazomethane, 4,6-dimethyl- 2-hydroxymethylphenylsulfonyl (4-fluorophenylsulfonyl) diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (2,3-dimethylphenylsulfonyl) diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (2,4-
Dimethylphenylsulfonyl) diazomethane, 4,6-
Dimethyl-2-hydroxymethylphenylsulfonyl (2,5-dimethylphenylsulfonyl) diazomethane, 4,6-dimethyl-2-hydroxymethylphenylsulfonyl (2,6-dimethylphenylsulfonyl) diazomethane, phenylsulfonyl (2-naphthylsulfonyl) Diazomethane, phenylsulfonyl (1-naphthylsulfonyl) diazomethane, 4-methoxyphenylsulfonyl (2-naphthylsulfonyl) diazomethane, 4
-Methoxyphenylsulfonyl (1-naphthylsulfonyl) diazomethane, cyclohexylsulfonyl (2-naphthylsulfonyl) diazomethane, cyclohexylsulfonyl (1-naphthylsulfonyl) diazomethane, 2,
Bissulfonyldiazomethanes such as 4,6-trimethylphenylsulfonyl (2-naphthylsulfonyl) diazomethane and 2,4,6-trimethylphenylsulfonyl (1-naphthylsulfonyl) diazomethane can be used, and these can be used alone. Good. Two or more kinds may be used as a mixture.

Of these acid generators, preferred are sulfonium salts in which the counter anion is sulfonic acid, iodonium salts in which the counter anion is sulfonic acid, sulfonic acid esters, o-nitrobenzylsulfonic acid esters, and sulfone hydrazides. , Bissulfonylmethanes, bissulfonyldiazomethanes, etc., which generate sulfonic acid by light or electron beam. More preferably, the counter anion is camphorsulfonic acid, p-toluenesulfonic acid,
Sulfonium salts and iodonium salts which are perfluoroalkylsulfonic acids, specific examples of which are triphenylsulfonium camphorsulfonate, triphenylsulfonium-p-toluenesulfonate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium perfluorobutanesulfonate, Bisphenyl (pt-butylphenyl) sulfonium camphorsulfonate, bis (pt-butylphenyl) phenylsulfonium camphorsulfonate, tris (pt-butylphenyl) sulfonium camphorsulfonate, tris (pt-butylphenyl) Sulfonium-p-toluenesulfonate, tris (pt-butylphenyl) sulfonium trifluoromethanesulfonate Tris (pt-butylphenyl) sulfonium perfluorobutanesulfonate, diphenyliodonium camphorsulfonate, diphenyliodonium-p-toluenesulfonate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium perfluorobutanesulfonate, bis (pt-butylphenyl) Iodonium camphorsulfonate, bis (pt-butylphenyl)
Iodonium-p-toluenesulfonate, bis (p-
t-butylphenyl) iodonium trifluoromethanesulfonate, bis (pt-butylphenyl) iodonium perfluorobutanesulfonate, and the like. In the radiation-sensitive resin composition of the present invention, a compound capable of generating an acid by radiation such as light or an electron beam is 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, based on the resin component described above. Used in the ratio of

(Aliphatic polyhydric alcohols) In the present invention,
In order to enhance the rectangularity of the resist pattern, aliphatic polyhydric alcohols can be added. Since the aliphatic polyhydric alcohol can uniformly dissolve the film during development, the film can be prevented from being roughened and the rectangularity can be improved. As the aliphatic polyhydric alcohols used in the present invention, a linear group which may have a substituent as long as the number of hydroxyl groups is 2 or more,
A branched or cyclic aliphatic polyhydric alcohol, or
Examples thereof include partially modified products in which a plurality of hydroxyl groups present in these compounds are partially modified to form an ether structure, an ester structure, or the like. The number of alcoholic hydroxyl groups is preferably 2 to 5, and the number of carbon atoms constituting the alcohol is 2 to 5.
20, particularly preferably 2 to 13, more preferably 3 to 11.

The boiling point or decomposition temperature of the aliphatic polyhydric alcohol is determined in consideration of the temperature in the step of forming a resist pattern using the radiation-sensitive resin composition of the present invention.
130 ° C. or higher is preferable, and 150 ° C. or higher is more preferable. The upper limit is not particularly limited, but is usually about 280 ° C. or less. Specific examples of the aliphatic polyhydric alcohols include 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 4-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 2,5-hexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol,
1,4-cyclohexanediol, 1,2-heptanediol, 1,7-heptanediol, 1,2-octanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, , 11-undecanol, 1,2-dodecanediol, 1,12-dodecanediol, 1,2-cyclododecanediol, glycerin-α-monomethyl ether, glycerin-α-
Monoacetate, glycerin-α-monocaprate, glycerin-α-monocaprylate, glycerin-α-monolaurate, glycerin-α-monooleate, glycerin-α-monopalmate, 1,2,4-butanetriol, 1,2 , 3-butanetriol, 2-butyl-2
-Ethyl-1,3-propanediol, 1,2,3-cyclohexanetriol, 1,3,5-cyclohexanetriol, 2-deoxy-D-galactose, 6-deoxy-D-galactose, 6-deoxy-L- Galactose, 2-deoxy-D-glucose, D-2-deoxyribose, adonitol, DL-arabinose, D
L-arabitol, pinacol, 2,2-dimethyl-
1,3-propanediol, 2-ethyl-1,3-hexanediol, lauric acid-2,3-dihydroxy-n
-Propyl, undecanoic acid-2,3-dihydroxy-n
-Propyl, 2,3-dihydroxy-n-propyl decanoate and the like. Among these, 1,4-butanediol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol,
1,4-cyclohexanediol, lauric acid-2,3
-Dihydroxy-n-propyl is preferred. These aliphatic polyhydric alcohols may be used alone or as a mixture of two or more. When these aliphatic polyhydric alcohols are used, they are contained in an amount of 0.5 to 20 parts by weight, preferably 1 to 15 parts by weight, based on the resin described above.

(Basic Organic Compound) In the present invention, a basic organic compound can be added in order to control the diffusion length of the acid generated by exposure to suppress the dimensional fluctuation of the pattern. The compound is a compound that acts as a base for the acid generated from the photoacid generator. That is, the compound is not particularly limited as long as it is a compound capable of neutralizing the acid generated from the photoacid generator as described above.However, when an inorganic compound is used as a base, a small amount of residue is generated after removing the resist after pattern formation, and adverse effects are caused. Organic bases are preferred because they give. The organic base is at least one kind of organic amine or acid amide compound selected from nitrogen-containing compounds.

Specifically, for example, pyrimidine, 2-aminopyrimidine, 4-aminopyrimidine, 5-aminopyrimidine, 2,4-diaminopyrimidine, 2,5-diaminopyrimidine, 4,5-diaminopyrimidine, 4,6 −
Diaminopyrimidine, 2,4,5-triaminopyrimidine, 2,4,6-triaminopyrimidine, 4,5,6-
Triaminopyrimidine, 2,4,5,6-tetraaminopyrimidine, 2-hydroxypyrimidine, 4-hydroxypyrimidine, 5-hydroxypyrimidine, 2,4-dihydroxypyrimidine, 2,5-dihydroxypyrimidine, 4,5-dihydroxy Pyrimidine, 4,6-dihydroxypyrimidine, 2,4,5-trihydroxypyrimidine, 2,4,6-trihydroxypyrimidine, 4,
5,6-trihydroxypyrimidine, 2,4,5,6-
Tetrahydroxypyrimidine, 2-amino-4-hydroxypyrimidine, 2-amino-5-hydroxypyrimidine, 2-amino-4,5-dihydroxypyrimidine, 2
-Amino-4,6-dihydroxypyrimidine, 4-amino-2,5-dihydroxypyrimidine, 4-amino-
2,6-dihydroxypyrimidine, 2-amino-4-methylpyrimidine, 2-amino-5-methylpyrimidine,
2-amino-4,5-dimethylpyrimidine, 2-amino-4,6-dimethylpyrimidine, 4-amino-2,5-
Dimethylpyrimidine, 4-amino-2,6-dimethylpyrimidine, 2-amino-4-methoxypyrimidine, 2-
Amino-5-methoxypyrimidine, 2-amino-4,5
-Dimethoxypyrimidine, 2-amino-4,6-dimethoxypyrimidine, 4-amino-2,5-dimethoxypyrimidine, 4-amino-2,6-dimethoxypyrimidine,
2-hydroxy-4-methylpyrimidine, 2-hydroxy-5-methylpyrimidine, 2-hydroxy-4,5-
Dimethylpyrimidine, 2-hydroxy-4,6-dimethylpyrimidine, 4-hydroxy-2,5-dimethylpyrimidine, 4-hydroxy-2,6-dimethylpyrimidine, 2-hydroxy-4-methoxypyrimidine, 2-hydroxy-5 -Methoxypyrimidine, 2-hydroxy-
4,5-dimethoxypyrimidine, 2-hydroxy-4,
6-dimethoxypyrimidine, 4-hydroxy-2,5-
Pyrimidine compounds such as dimethoxypyrimidine and 4-hydroxy-2,6-dimethoxypyrimidine, triethylamine, diethyl-n-propylamine, diethyl-n
Alkylamines such as butylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, diethanolamine, triethanolamine, triisopronolamine, tris (hydroxymethyl) aminomethane, bis (2- Amines substituted with a hydroxyalkyl group such as hydroxyethyl) aminotris (hydroxymethyl) methane, pyridine, 4-methylpyridine, 3-methylpyridine, 2-methylpyridine, 4- (hydroxymethyl) pyridine, 3- ( Hydroxymethyl) pyridine, 2
-(Hydroxymethyl) pyridine, 4- (2-hydroxyethyl) pyridine, 3- (2-hydroxyethyl) pyridine, 2- (2-hydroxyethyl) pyridine, 4-
Pyridines such as (N, N-dimethylamino) pyridine,
Aminophenols such as 2-aminophenol, 3-aminophenol, 4-aminophenol, N-propylacetamide, N-methylacetamide, N, N-dimethylacetamide, N, N-dimethylformamide, N
Examples thereof include primary amides such as -methylpyrrolidone, and the like, and amines and pyridines substituted with a hydroxyalkyl group are preferably used alone or in combination.

The content of the basic organic compound in the radiation-sensitive composition of the present invention is preferably from 0.1 to 500 mol%, more preferably from the content of the above-mentioned photoacid generator, depending on the basicity. , 1 to 300 mol%. 0.1
When the amount is less than mol%, the environment dependency is high and unstable, and when the amount is more than 500%, the sensitivity tends to be low.

(Other Additives and Solvents) The radiation-sensitive composition of the present invention may further contain, if necessary, an organic carboxylic acid, alcohol, dye, pigment, coatability improver, etc., in addition to the above components. be able to. The radiation-sensitive composition of the present invention,
The above components are uniformly dissolved in an appropriate solvent and used. Examples of the solvent include cellosolve solvents such as methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, and ethyl cellosolve acetate, diethyl oxalate, ethyl pyruvate, ethyl-2-hydroxybutyrate, ethyl acetoacetate, butyl acetate, and amyl acetate. Ethyl acetate, butyl butyrate, methyl lactate, ethyl lactate, ester solvents such as methyl 3-methoxypropionate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol mono Ethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol dimethyl ether, etc. B propylene glycol based solvent, 2-hexanone, cyclohexanone, methyl amyl ketone, 2
And ketone solvents such as heptanone, or a mixed solvent thereof, or a solvent to which an aromatic hydrocarbon is further added.

The organic carboxylic acid is added for the purpose of reducing the tailing of the resist pattern or reducing the edge roughness, and specific examples thereof include saturated aliphatic carboxylic acids such as butyric acid and malonic acid, and 1,4- Alicyclic carboxylic acids such as cyclohexanedicarboxylic acid, benzoic acid, o-, m
-Or p-hydroxybenzoic acid, terephthalic acid, SAX
(Trade name, manufactured by Mitsui Chemicals, Inc.) and the like, and may be used alone or in combination of two or more.

Alcohol is added for the purpose of reducing particles during film formation, and is preferably a monohydric alcohol having a boiling point of 100 ° C. or lower. Specific examples include methanol, ethanol, n- or iso-propanol. Examples of the coating improver include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether and polyoxyethylene oleyl ether; polyoxyethylene such as polyoxyethylene octyl phenol ether and polyoxyethylene nonyl phenol ether. Nonionic surfactants such as alkyl phenol ethers and polyethylene glycol dialkyl ethers such as polyethylene glycol dilaurate and polyethylene glycol distearate; EFTOP EF301, EF3
03, EF352 (manufactured by Mitsubishi Materials Corporation), Megafac F171, F173, F179, R08 (manufactured by Dainippon Ink Co., Ltd.), alkyl fluoride group or perfluoro group exemplified in JP-A-57-178242. Florad F, a linear fluorinated surfactant having an alkyl group
C430, FC431 (manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC1
01, SC102, SC103, SC104, SC10
5. Fluorinated surfactants such as SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid or methacrylic acid (co) polymer polyflow No. 75, No. 95 (Kyoeisha) And the like, and can be used alone or in combination of two or more. The content of the coating property improving agent is usually 10 to 500 ppm based on the radiation-sensitive coating composition.

Next, a method for forming a resist pattern using the radiation-sensitive composition of the present invention will be described. The radiation-sensitive composition of the present invention dissolved in a solvent as described above is applied onto a semiconductor substrate, and a resist pattern can be obtained through each of prebaking, pattern transfer by exposure, heating after exposure, and development. The semiconductor substrate is usually used as a substrate for manufacturing a semiconductor, and is a silicon substrate, a gallium arsenide substrate, or the like. Usually, a spin coater is used for coating, and 436 nm of a high-pressure mercury lamp is used for exposure.
Light, 365 nm light, 254 nm light from a low-pressure mercury lamp, or 248 nm light using an excimer laser or the like as a light source, 222 n
m light, 193 nm light, 157 nm light, X-ray, electron beam, or the like is used. Light at the time of exposure may be broad instead of monochromatic light. Exposure by a phase shift method is also applicable. Examples of the developer include inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; diethylamine; secondary amines such as n-propylamine; tertiary amines such as triethylamine and N, N-diethylmethylamine; quaternary ammonium salts such as tetramethylammonium hydroxide and trimethylhydroxyethylammonium hydroxide; or What added alcohol, surfactant, etc. to this can be used. The radiation-sensitive composition of the present invention is useful not only for the production of VLSI, but also for general IC production, mask production, image formation, liquid crystal screen production, color filter production, or offset printing.

[0045]

Next, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited by the examples unless it exceeds the gist thereof. Table 1 shows the structures of the polymerized units of the copolymer resins used in the examples and comparative examples and their ratios.

Examples 1 to 5 and Comparative Examples 1 to 8 Resins (A), photoacid generators (B), organic bases (C) and additives (D) were mixed with propylene glycol in accordance with the proportions shown in Table 2 below. After dissolving in monomethyl ether acetate (E), the solution was finely filtered through a membrane filter having a pore size of 0.2 μm to prepare a resist photosensitive solution. Lower anti-reflective coating (DUV4 manufactured by Brewer Science)
2,800 °) is spin-coated with the resist photosensitive solution shown in Table 1 on a hot plate.
Prebake at 15 ° C for 90 seconds to form a film with a thickness of 0.72 µm
Was formed. Further, an aqueous solution containing 1.2% by weight of polyvinylpyrrolidone and 3.5% by weight of ammonium perfluorooctylsulfonate was applied on the resist film to form an antireflection film for an upper layer. The resist film on the silicon substrate is subjected to a Nikon KrF excimer laser reduction projection exposure apparatus (NA = 0.50, σ = 0.4) and a halftone mask (transmittance 6%, 0.30 μμ hole, 0.90 μm pitch) (Manufactured by Dai Nippon Printing Co., Ltd.), and post-exposure bake was performed on a hot plate at 110 ° C. for 90 seconds. Thereafter, the resist film was paddle-developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide for 1 minute and washed with water to form a resist pattern. The obtained resist pattern was observed and evaluated with a scanning electron microscope. The evaluation criterion was that the exposure amount at which the hole pattern had a diameter of 0.24 μm and resolved was defined as the effective sensitivity, and the quotient of the exposure amount at which dimples were generated and the effective sensitivity was defined as the dimple margin. The aperture DOF is a focus margin in which the hole pattern is resolved in the effective sensitivity, and the shape DOF is a focus margin in the effective sensitivity in which the hole pattern is resolved and no dimple is generated. Table 3 summarizes the results.

[0047]

[Table 1]

[0048]

[Table 2]

A-1: p-hydroxystyrene, p-
(T-butoxycarbonyloxy) styrene and p-
(1-ethoxyethyloxy) styrene copolymer resin (composition ratio is about 70: 5: 25 in molar ratio) A-2: p-hydroxystyrene, p- (t-butoxycarbonyloxy) styrene and p- (1 -Ethoxyethyloxy) styrene copolymer resin (composition ratio is about 60: 5: 35 by mole ratio) A-3: Copolymer resin of p-hydroxystyrene, styrene and t-butyl acrylate (composition ratio is molar About 6 in ratio
5:15:20) A-4: Copolymer resin of p-hydroxystyrene, styrene and tert-butyl acrylate (composition ratio is about 7 in molar ratio)
0:20:10) A-5: Copolymer resin of p-1-ethoxyethoxystyrene and p-hydroxystyrene (composition ratio is about 3 by mole ratio)
5:65) A-6: Copolymer resin of p-hydroxystyrene and p- (t-butoxycarbonyloxy) styrene (composition ratio is about 70:30 in molar ratio) A-7: Poly-p- (t- Butoxycarbonyloxy)
Styrene A-8: Copolymer resin of p-1-ethoxyethoxystyrene, p-hydroxystyrene, styrene and t-butyl acrylate (composition ratio is about 25:45:20:
10) A-9: Copolymer resin of p- (t-butoxycarbonyloxy) styrene, p-hydroxystyrene, styrene and t-butyl acrylate (composition ratio is about 5: 6 in molar ratio)
5:20:10) B: triphenylsulfonium trifluoromethanesulfonate C: tri-iso-propanolamine D-1: 1,4-cyclohexanediol D-2: o-hydroxybenzoic acid F: propylene glycol monomethyl ether acetate m1: Monomer unit of vinyl group of p-hydroxystyrene cleaved m2: Monomer unit of vinyl group of p-1-ethoxyethyloxystyrene cleaved m3: Monomer unit of vinyl group of p-t-butoxycarbonyloxystyrene cleaved m4: Monomer unit in which vinyl group of tert-butyl acrylate has been cleaved m5: Monomer unit in which vinyl group of styrene has been cleaved

[0050]

[Table 3]

[0051]

According to the present invention, the resolution, the depth of focus, the dimensional controllability, and the heat resistance are excellent, and particularly, the dimple resistance when a hole pattern is formed using a halftone mask is excellent, and A radiation-sensitive resin composition exhibiting a wide focus margin can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/004 501 G03F 7/004 501 // (C08F 212/14 (C08F 212/14 220: 10) 220 : 10) (71) Applicant 596 156 668 455 Forest Street, Marlborough, MA 01752 U.S.A. A (72) Inventor Yasuhiro Kameyama 1-1 Kurosaki Castle Stone, Yawatanishi-ku, Kitakyushu City F-term (reference) 2K025 AA00 AA02 AA03 AA10 AB16 AC06 AD03 BE00 BG00 CC20 FA03 FA12 FA17 4J002 BC12W BC12X EB046 EB076 EB076 EB076 EB076 EB076 EB076 EB076 EB076 EB076 EB076 EC047 EC057 EU186 EU196 EV216 EV236 EV256 EV266 EV296 FD206 FD207 GP03 4J100 AB07P AB07Q AB07R AL03S AL04S AL05S AL08S AL16S BA02Q BA03P BA04Q BA04S BA05Q BA05S BA06Q BA06S BA15R BC03Q BC04Q BC04SBC07S BC09 BC04 BC07 BC38

Claims (9)

[Claims] 1. A resin component (A) which is alkali-insoluble or hardly soluble in alkali and becomes alkali-soluble by the action of an acid, and a compound (B) which generates an acid by light or electron beam
And (A) contains at least one polymerized unit represented by the following general formulas [1] to [4], and is polymerized as a whole resin contained in (A). Units [1], [2], [3] and [4]
A radiation-sensitive resin composition comprising: Embedded image (In the formulas [1] to [4], R ¹ , R ⁵ , R ⁷ and R ⁹ each independently represent a hydrogen atom, a carbon atom of 1 to 1;
0 alkyl group, an alkenyl group having 2 to 10 carbon atoms, indicates an alkynyl group, an aralkyl group having 7 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms having 2 to 10 carbon atoms, R ²
And R ³ each independently represent a hydrogen atom, a carbon number of 1 to
R represents an alkyl group having 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms;
⁴ represents an alkyl group having 1 to 20 carbon atoms, and R ⁶ and R ⁸
Each independently represents an organic residue having 1 to 20 carbon atoms. R ³ and R ⁴ are bonded to each other to form a ring —OR ′
-(Where R 'represents an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms or an alkynylene group having 2 to 20 carbon atoms). 2. The molar ratio of the polymer units [1], [2], [3] and [4] to the total number of moles of all the polymer units contained in (A) is 10 to 50 mol%, respectively. 0.
The radiation-sensitive resin composition according to claim 1, wherein the content is 5 to 20 mol%, 0.5 to 20 mol%, and 40 to 85 mol%. 3. A copolymer in which (A) contains polymerized units represented by formulas [1], [2] and [4], and a polymerized unit represented by formulas [3] and [4]. The radiation-sensitive resin composition according to claim 1, further comprising a copolymer. 4. In the formula [2], R ⁶ has 4 to 2 carbon atoms.
2. A tertiary alkyl group of 0.
4. The radiation-sensitive resin composition according to any one of items 1 to 3. 5. In the formula [3], R ⁸ has 4 to 2 carbon atoms.
The radiation-sensitive resin composition according to any one of claims 1 to 4, wherein the composition is a linear, branched, or alicyclic alkyl group. 6. In the formula [3], R ⁸ has 4 to 20 carbon atoms.
The radiation-sensitive resin composition according to any one of claims 1 to 5, which is a branched or alicyclic tertiary alkyl group. 7. The radiation-sensitive resin composition according to claim 1, further comprising an aliphatic polyhydric alcohol. 8. The radiation-sensitive resin composition according to claim 7, wherein the number of hydroxyl groups in the aliphatic polyhydric alcohol is 2 to 5. 9. The radiation-sensitive resin composition according to claim 7, wherein the aliphatic polyhydric alcohol constituting the aliphatic polyhydric alcohol has 2 to 20 carbon atoms.