Resist polymer, resist composition, process for pattern formation, and starting compounds for production of the resist polymer
View Patent ↗To provide a resist polymer comprising, as a structural unit, an acid-decomposable unit having a structure represented by formula (1) or (2) which exhibits a small line edge roughness and produces little defects in DUV excimer laser lithography or the like. In formulas (1) and (2), n represents an integer of 2 to 24; J represents a single bond or a divalent hydrocarbon group which may have a substituent/heteroatom when n=2, or represents an n-valent hydrocarbon group which may have a substituent/heteroatom when n≧3; E represents a residue of a polymerization terminator, a chain transfer agent or a polymerization initiator; K 1 and K 2 each represent at least one selected from alkylene, cycloalkylene, oxyalkylene, arylene, a divalent thiazoline ring, a divalent oxazoline ring and a divalent imidazoline ring; L 1 and L 2 each represent at least one selected from —C(O)O—, —C(O)— and —OC(O)—; M 1 , M 2 and M 3 each represent at least one selected from alkylene, cycloalkylene, oxyalkylene and arylene; Y, Y 1 and Y 2 each represent an acid-decomposable linkage; k1, k2, l1, l2, m1, m2, and m3 each represent 0 or 1; and R 1 represents H or a methyl group.
1. A compound represented by formula (6):
wherein
J is selected from the group consisting of:
E 1 represents a functional group having polymerization termination ability or chain transfer ability;
K 1 and K 2 each independently represent at least one selected from the group consisting of alkylene, cycloalkylene, oxyalkylene, arylene, a divalent thiazoline ring, a divalent oxazoline ring and a divalent imidazoline ring;
L 1 and L 2 each independently represent at least one selected from the group consisting of —C(O)O—, —C(O)— and —OC(O)—;
M 1 and M 2 each independently represent at least one selected from the group consisting of alkylene, cycloalkylene, oxyalkylene and arylene;
Y represents an acid-decomposable linkage;
n represents an integer corresponding to the valencies of J; and
k1, k2, l1, l2, m1 and m2 each represent the number of K 1 , K 2 , L 1 , L 2 , M 1 and M 2 , respectively, and are each independently 0 or 1.
2. The compound represented by formula (6) according to claim 1 , wherein E 1 is at least one member selected from the group consisting of a hydroxyl group, a thiol group, an alkyl group substituted with a halogen atom, and a nitroxide radical.
3. The compound according to claim 1 , wherein J is
4. The compound according to claim 1 , wherein J is
5. The compound according to claim 1 , wherein J is
6. The compound according to claim 1 , wherein J is
7. The compound according to claim 1 , wherein J is
8. A compound represented by formula (7):
wherein
S represents a sulfur atom;
K 1 and K 2 each independently represent at least one selected from the group consisting of alkylene, cycloalkylene, oxyalkylene, arylene, a divalent thiazoline ring, a divalent oxazoline ring and a divalent imidazoline ring;
L 1 and L 2 each independently represent at least one selected from the group consisting of —C(O)O—, —C(O)— and —OC(O)—;
M 1 to M 3 each independently represent at least one selected from the group consisting of alkylene, cycloalkylene, oxyalkylene and arylene;
Y 1 and Y 2 each independently represent an acid-decomposable linkage;
k1, k2, l1, l2, m1, m2, and m3 each represent the number of K 1 , K 2 , L 1 , L 2 , M 1 , M 2 , M 3 and Y 2 , respectively, and are each independently 0 or 1; and
n1 represents the number of Y 2 and is 1.
9. The compound according to claim 8 , which is obtained by a method comprising adding a carboxylic acid having a sulfur atom represented by formula (21) to a divinyl ether represented by formula (20) to obtain a compound represented by formula (22), and thereafter dithiolating the compound represented by formula (22):
wherein
M 2 represents alkylene, cycloalkylene, oxyalkylene or arylene;
m2 represents 1;
S represents a sulfur atom;
Z 2 represents an acyl group; and
K 1 represents at least one selected from the group consisting of alkylene, cycloalkylene, oxyalkylene, arylene, a divalent thiazoline ring, a divalent oxazoline ring and a divalent imidazoline ring.
10. The compound according to claim 9 , wherein said divinyl ether represented by formula (20) is at least one member selected from the group consisting of:
11. The compound according to claim 9 , wherein said carboxylic acid having a sulfur atom represented by formula (21) is at least one member selected from the group consisting of:
12. The compound according to claim 9 , wherein said carboxylic acid having a sulfur atom represented by formula (21) is present in an amount of from 2 to 8 times the amount of said divinyl ether on a per molar basis.
13. A compound selected from the group consisting of: