RADIATION-SENSITIVE COMPOSITION AND METHOD OF FORMING RESIST PATTERN
A radiation-sensitive composition includes: a polymer comprising a first structural unit represented by formula (1); and a compound comprising an anion and a radiation-sensitive onium cation. At least one of the polymer and the compound has a ring structure having at least one iodine atom bonded to the ring structure. R 1 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; L 1 represents a single bond, —COO—, or —CONH—; Ar 1 represents a group obtained by removing two hydrogen atoms from a substituted or unsubstituted aromatic hydrocarbon ring; and R 2 represents an acid-labile group.
1 . A radiation-sensitive composition comprising:
a polymer comprising a first structural unit represented by formula (1); and
a compound comprising an anion and a radiation-sensitive onium cation, wherein
at least one of the polymer and the compound has a ring structure having at least one iodine atom bonded to the ring structure,
wherein, in the formula (1), R 1 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; L 1 represents a single bond, —COO—, or —CONH—; Ar 1 represents a group obtained by removing two hydrogen atoms from a substituted or unsubstituted aromatic hydrocarbon ring; and R 2 represents an acid-labile group.
2 . The radiation-sensitive composition according to claim 1 , wherein the acid-labile group does not comprise a polycyclic aliphatic ring.
3 . The radiation-sensitive composition according to claim 1 , wherein the acid-labile group comprises an aromatic ring or a carbon-carbon double bond.
4 . The radiation-sensitive composition according to claim 1 , wherein the acid-labile group comprises an aromatic ring having at least one iodine atom bonded to the aromatic ring.
5 . The radiation-sensitive composition according to claim 1 , wherein the radiation-sensitive onium cation further comprises an aromatic ring having at least one fluorine atom or at least one fluorine atom-containing group, the at least one fluorine atom and the at least one fluorine atom-containing group being bonded to the aromatic ring.
6 . The radiation-sensitive composition according to claim 1 , wherein the polymer further comprises a second structural unit comprising a ring structure having at least one iodine atom bonded to the ring structure.
7 . The radiation-sensitive composition according to claim 6 , wherein the ring structure comprised in the second structural unit is an aromatic ring having at least one iodine atom bonded to the aromatic ring.
8 . A method of forming a resist pattern, the method comprising:
applying the radiation-sensitive composition according to claim 1 directly or indirectly on a substrate to form a resist film;
exposing the resist film; and
developing the resist film exposed.
9 . The method according to claim 8 , wherein the acid-labile group does not comprise a polycyclic aliphatic ring.
10 . The method according to claim 8 , wherein the acid-labile group comprises an aromatic ring or a carbon-carbon double bond.
11 . The method according to claim 8 , wherein the acid-labile group comprises an aromatic ring having at least one iodine atom bonded to the aromatic ring.
12 . The method according to claim 8 , wherein the radiation-sensitive onium cation further comprises an aromatic ring having at least one fluorine atom or at least one fluorine atom-containing group, the at least one fluorine atom and the at least one fluorine atom-containing group being bonded to the aromatic ring.
13 . The method according to claim 8 , wherein the polymer further comprises a second structural unit comprising a ring structure having at least one iodine atom bonded to the ring structure.
14 . The method according to claim 13 , wherein the ring structure comprised in the second structural unit is an aromatic ring having at least one iodine atom bonded to the aromatic ring.