Onium salt, chemically amplified positive resist composition, and patterning process

Patent metadata

Field	Value
Publication number	US-9535325-B2
Application number	US-201414573871-A
Country	US
Kind code	B2
Filing date	Dec 17, 2014
Priority date	Jan 10, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

The present invention provides the onium salt comprises the material represented by the following general formula (0-1),

wherein R f represents a fluorine atom or a trifluoromethyl group; Y represents a cyclic hydrocarbon group having 3 to 30 carbon atoms, the hydrogen atom in the cyclic hydrocarbon group may be substituted by a hetero atom itself or a monovalent hydrocarbon group which may be substituted by a hetero atom(s), and the hetero atom(s) may be interposed into the cyclic structure of the cyclic hydrocarbon group and the monovalent hydrocarbon group; and M + represents a monovalent cation.

There can be provided an onium salt which can improve resolution at the time of forming a pattern and give a pattern with less line edge roughness (LER) when it is used in a chemically amplified positive resist composition.

First claim

What is claimed is:

1. An onium salt represented by the following general formula (1) or (2),

wherein R f represents a fluorine atom or a trifluoromethyl group; M + represents a monovalent cation; X represents O or CH 2 ; k 1 represents an integer of 0 to 2; and Z 1 , Z 2 , Z 3 , Z 4 , Z 5 and Z 6 each independently represent a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted by a hetero atom(s), and a hetero atom(s) may be interposed in the monovalent hydrocarbon group,

wherein R f , X, k 1 , Z 1 , Z 2 , Z 5 , Z 6 and M + have the same meanings as defined above.

2. A chemically amplified positive resist composition which comprises the onium salt defined in claim 1 , a resin having a group which can be decomposed by an acid, and a photoacid generator.

3. The chemically amplified positive resist composition according to claim 2 , wherein the resin contains a repeating unit represented by the following general formula (3),

wherein “s” represents 0 or 1; “t” represents an integer of 0 to 2; R 1 represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; each R 2 independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; B 1 represents a single bond or an alkylene group having 1 to 10 carbon atoms which may contain an ether bond(s); “c” represents an integer satisfying c≦5+2t−e; “d” represents 0 or 1; “e” represents an integer of 1 to 3; and X′ represents an acid-labile group when “e” represents 1, and represents a hydrogen atom or an acid-labile group when “e” represents 2 or more, and at least one of which represent an acid-labile group.

4. The chemically amplified positive resist composition according to claim 2 , wherein the resin contains a repeating unit represented by the following general formula (4),

wherein “q” represents 0 or 1; “r” represents an integer of 0 to 2; R 1 represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; each R 2 independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; B 1 represents a single bond or an alkylene group having 1 to 10 carbon atoms which may contain an ether bond(s); “a” represents an integer satisfying a≦5+2r−b; and “b” represents an integer of 1 to 3.

5. The chemically amplified positive resist composition according to claim 3 , wherein the resin contains a repeating unit represented by the following general formula (4),

wherein “q” represents 0 or 1; “r” represents an integer of 0 to 2; R 1 represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; each R 2 independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; B 1 represents a single bond or an alkylene group having 1 to 10 carbon atoms which may contain an ether bond(s); “a” represents an integer satisfying a≦5+2r−b; and “b” represents an integer of 1 to 3.

6. The chemically amplified positive resist composition according to claim 2 , wherein the resin contains a repeating unit represented by the following general formula (5) or a repeating unit represented by the following general formula (6), or both of them,

wherein “f” represents an integer of 0 to 6; each R 3 independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may be substituted by a halogen atom(s), a primary or secondary alkoxy group which may be substituted by a halogen atom(s), or an alkylcarbonyloxy group having 1 to 7 carbon atoms which may be substituted by a halogen atom(s); “g” represents an integer of 0 to 4; each R 4 independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may be substituted by a halogen atom(s), a primary or secondary alkoxy group which may be substituted by a halogen atom(s), or an alkylcarbonyloxy group having 1 to 7 carbon atoms which may be substituted by a halogen atom(s).

7. The chemically amplified positive resist composition according to claim 2 , wherein the composition further comprises a basic compound.

Assignees

• Shinetsu Chemical Co

Inventors

• Domon Daisuke
• Masunaga Keiichi
• Watanabe Satoshi
• Fukushima Masahiro
• Hasegawa Koji

Classifications

• C07C61/29

  having a carboxyl group bound to a condensed ring system · CPC title

• G03F7/0397

  the macromolecular compound having an alicyclic moiety in a side chain · CPC title

• C07C61/125

  having a carboxyl group bound to a condensed ring system · CPC title

• G03F7/322

  Aqueous alkaline compositions · CPC title

• G03F7/0392 Primary

  the macromolecular compound being present in a chemically amplified positive photoresist composition · CPC title