PHOTORESIST COMPOSITION
A photoresist composition includes a base polymer, a polymer and an acid generator. The base polymer includes a first structural unit that includes an acid-labile group. The polymer includes a second structural unit that includes an acid-labile group, and has a fluorine atom content higher than a fluorine atom content of the base polymer. The photoresist composition is developed using an organic solvent. The second structural unit is represented by a formula (1) or a formula (2). R 1 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. Z 1 is a divalent monocyclic hydrocarbon group having 5 or 6 carbon atoms or a divalent polycyclic hydrocarbon group having 7 to 10 carbon atoms. R 2 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R 3 is an alicyclic hydrocarbon group having 5 to 20 carbon atoms.
1 . A photoresist composition comprising:
a base polymer that includes a first structural unit that includes an acid-labile group;
a polymer that includes a second structural unit that includes an acid-labile group, and has a fluorine atom content higher than a fluorine atom content of the base polymer; and
an acid generator,
the photoresist composition being developed using an organic solvent,
the second structural unit being represented by a formula (1) or a formula (2),
wherein
R 1 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group,
Z 1 is a divalent monocyclic hydrocarbon group having 5 or 6 carbon atoms or a divalent polycyclic hydrocarbon group having 7 to 10 carbon atoms,
R 2 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group, and
R 3 is an alicyclic hydrocarbon group having 5 to 20 carbon atoms.
2 . The photoresist composition according to claim 1 , wherein the first structural unit is a structural unit represented by a formula (3) or a formula (4),
wherein
R 4 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group,
R 5 is an alkyl group having 1 to 5 carbon atoms,
n is 0 or 1,
R 6 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group,
R 7 is an alkyl group having 2 to 5 carbon atoms, and
Z 2 is a divalent monocyclic hydrocarbon group having 5 or 6 carbon atoms or a divalent polycyclic hydrocarbon group having 7 to 15 carbon atoms.
3 . The photoresist composition according to claim 1 , wherein the polymer further includes a third structural unit represented by a formula (5),
wherein
R 8 is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group,
X is a linking group, and
R 9 is a linear or branched alkyl group having 1 to 10 carbon atoms or an alicyclic hydrocarbon group having 4 to 20 carbon atoms, wherein some or all of the hydrogen atoms of the alkyl group or the alicyclic hydrocarbon group represented by R 9 are substituted with a substituent, at least one substituent that substitutes some or all of the hydrogen atoms of the alkyl group or the alicyclic hydrocarbon group represented by R 9 being a fluorine atom.