RADIATION-SENSITIVE RESIN COMPOSITION AND RESIST PATTERN-FORMING METHOD
A radiation-sensitive resin composition includes: a first polymer having a first structural unit which includes a phenolic hydroxyl group, and a second structural unit which includes an acid-labile group and a carboxy group which is protected by the acid-labile group; a second polymer having a third structural unit represented by the following formula (S-1), and a fourth structural unit which is a structural unit other than the third structural unit and is represented by the following formula (S-2); and a radiation-sensitive acid generator, wherein the acid-labile group includes a monocyclic or polycyclic ring structure having no fewer than 3 and no more than 20 ring atoms.
1 . A radiation-sensitive resin composition comprising:
a first polymer comprising a first structural unit which comprises a phenolic hydroxyl group, and a second structural unit which comprises an acid-labile group and a carboxy group which is protected by the acid-labile group;
a second polymer comprising a third structural unit represented by formula (S-1), and a fourth structural unit which is a structural unit other than the third structural unit and is represented by formula (S-2); and
a radiation-sensitive acid generator, wherein
the acid-labile group comprises a monocyclic or polycyclic ring structure having no fewer than 3 and no more than 20 ring atoms,
wherein, in the formula (S-1), R F represents a hydrogen atom, a fluorine atom, or a monovalent organic group having 1 to 20 carbon atoms; R U represents a single bond or a divalent organic group having 1 to 20 carbon atoms; R 10 represents a fluorine atom or a monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms; and R 11 represents a hydrogen atom, a fluorine atom, a monovalent hydrocarbon group having 1 to 20 carbon atoms, or a monovalent fluorinated hydrocarbon group having 1 to 20 carbon atoms, and
in the formula (S-2), R G represents a hydrogen atom, a fluorine atom, or a monovalent organic group having 1 to 20 carbon atoms; R V represents a single bond or a divalent organic group having 1 to 20 carbon atoms; and R W represents a monovalent organic group having 1 to 20 carbon atoms which comprises a fluorine atom and does not comprise an alkali-labile group.
2 . The radiation-sensitive resin composition according to claim 1 , wherein
the second polymer further comprises a fifth structural unit which comprises an acid-labile group, and
a molar percentage of the fifth structural unit in the second polymer is greater than a sum of: in the first polymer, a molar percentage of the second structural unit, and a molar percentage of a structural unit which is a structural unit other than the second structural unit and comprises the acid-labile group.
3 . The radiation-sensitive resin composition according to claim 2 , wherein
the molar percentage of the fifth structural unit in the second polymer is 45 mol % or more.
4 . The radiation-sensitive resin composition according to claim 2 , wherein
the molar percentage of the fifth structural unit in the second polymer is 55 mol % or more.
5 . The radiation-sensitive resin composition according to claim 2 , wherein the second structural unit and the fifth structural unit are each independently represented by formula (S-3):
wherein, in the formula (S-3), R A represents a hydrogen atom, a fluorine atom, or a monovalent organic group having 1 to 20 carbon atoms; R X represents a single bond or a divalent organic group having 1 to 20 carbon atoms; R 1A represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; R 2A represents a monovalent hydrocarbon group having 1 to 20 carbon atoms and R 3A represents a monovalent organic group having 1 to 20 carbon atoms, or R 2A and R 3A taken together represent a monocyclic or polycyclic ring structure having 3 to 20 ring atoms together with the carbon atom to which R 2A and R 3A bond, wherein in a case in which R 2A represents the monovalent hydrocarbon group having 1 to 20 carbon atoms and R 3A represents the monovalent organic group having 1 to 20 carbon atoms, at least one of R 1A , R 2A , and R 3A comprises a monocyclic or polycyclic ring structure having 3 to 20 ring atoms.
6 . The radiation-sensitive resin composition according to claim 5 , wherein
R 1A in the formula (S-3) in the second structural unit represents an alkyl group having no fewer than 3 carbon atoms, and
R 1A in the formula (S-3) in the fifth structural unit represents an alkyl group having no fewer than 2 carbon atoms.
7 . The radiation-sensitive resin composition according to claim 1 , which is suitable for an exposure to an extreme ultraviolet ray or an exposure to an electron beam.
8 . A resist pattern-forming method comprising:
forming a resist film directly or indirectly on a substrate by applying the radiation-sensitive resin composition according to claim 1 ;
exposing the resist film; and
developing the resist film exposed.
9 . The resist pattern-forming method according to claim 8 , wherein in the exposing, the resist film is exposed to an extreme ultraviolet ray or an electron beam.
10 . The resist pattern-forming method according to claim 8 , wherein
the second polymer further comprises a fifth structural unit which comprises an acid-labile group, and
a molar percentage of the fifth structural unit in the second polymer is greater than a sum of: in the first polymer, a molar percentage of the second structural unit, and a molar percentage of a structural unit which is a structural unit other than the second structural unit and comprises the acid-labile group.
11 . The resist pattern-forming method according to claim 10 , wherein
the molar percentage of the fifth structural unit in the second polymer is 45 mol % or more.
12 . The resist pattern-forming method according to claim 10 , wherein
the molar percentage of the fifth structural unit in the second polymer is 55 mol % or more.
13 . The resist pattern-forming, method according to claim 10 , wherein the second structural unit and the fifth structural unit are each independently represented by formula (S-3):
wherein, in the formula (S-3), R A represents a hydrogen atom, a fluorine atom, or a monovalent organic group having 1 to 20 carbon atoms; R X represents a single bond or a divalent organic group having 1 to 20 carbon atoms; R 1A represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; R 2A represents a monovalent hydrocarbon group having 1 to 20 carbon atoms and R 3A represents a monovalent organic group having 1 to 20 carbon atoms, or R 2A and R 3A taken together represent a monocyclic or polycyclic ring structure having 3 to 20 ring atoms together with the carbon atom to which R 2A and R 3A bond, wherein in a case in which R 2A represents the monovalent hydrocarbon group having 1 to 20 carbon atoms and R 3A represents the monovalent organic group having 1 to 20 carbon atoms, at least one of R 1A , R 2A , and R 3A comprises a monocyclic or polycyclic ring structure having 3 to 20 ring atoms.
14 . The resist pattern-forming method according to claim 13 , wherein
R 1A in the formula (S-3) in the second structural unit represents an alkyl group having no fewer than 3 carbon atoms, and
R 1A in the formula (S-3) in the fifth structural unit represents an alkyl group having no fewer than 2 carbon atoms.