Photobase generators and photoresist compositions comprising same
New photobase generators suitable for use in photoresists are provided that correspond to Formula (I): X 1 —R 1 —O—C(═O)N(R 2 )R 3 (I) wherein X 1 is an optionally substituted aromatic group; R 1 is a linker; and R 2 and R 3 are the same or different optionally substituted linear, branched or cyclic aliphatic group or an optionally substituted aromatic group, wherein at least one of R 2 and R 3 is an optionally substituted branched alkyl group having 4 or more carbon atoms.
1. A method for forming a photolithographic pattern, comprising:
(a) applying a layer of a positive-acting photoresist composition on a substrate, the photoresist composition comprising (1) a resin comprising photoacid-labile groups; (2) one or more acid generators; and (3) a photobase generator that corresponds to the following Formula (IA):
X 1 —(CYZ) n —O—C(═O)N(R 2 )R 3 (IA)
wherein X 1 is an optionally substituted aromatic group;
each Y and Z is independently hydrogen or a non-hydrogen substituent;
n is a positive integer; and
R 2 and R 3 are the same or different,
optionally substituted branched alkyl group having 4 or more carbon atoms; and
(b) patternwise exposing the photoresist composition layer to activating radiation; and
(c) developing the exposed photoresist composition layer to provide a photoresist relief image.
2. The method of claim 1 wherein X 1 is optionally substituted anthracenyl or phenyl.
3. The method of claim 1 wherein R 2 and R 3 are each independently optionally substituted branched alkyl having 6 or more carbon atoms.
4. The method of claim 1 wherein R 2 and/or R 3 are fluorinated branched alkyl having 4 or more carbon atoms.
5. The method of claim 1 wherein the photobase generator is selected from among the following:
6. The method of claim 1 wherein the substrate is a semiconductor substrate.
7. A positive-acting photoresist composition comprising:
(1) a resin comprising photoacid-labile groups;
(2) one or more acid generators; and
(3) a photobase generator that corresponds to the following Formula (IA):
X 1 —(CYZ) n —O—C(═O)N(R 2 )R 3 (IA)
wherein X 1 is an optionally substituted aromatic group;
each Y and Z is independently hydrogen or a non-hydrogen substituent;
n is a positive integer; and
R 2 and R 3 are the same or different
optionally substituted branched alkyl group having 4 or more carbon atoms.
8. The photoresist composition of claim 7 wherein X 1 is optionally substituted anthracenyl or phenyl.
9. The photoresist composition of claim 7 wherein R 2 and R 3 are each independently optionally substituted branched alkyl having 6 or more carbon atoms.
10. The photoresist composition of claim 7 wherein R 2 and/or R 3 are fluorinated branched alkyl having 4 or more carbon atoms.
11. The photoresist composition of claim 7 wherein the photobase generator is selected from among the following:
12. A positive-acting photoresist composition comprising:
(1) a resin;
(2) one or more acid generators; and
(3) a photobase generator that corresponds to the following Formula (TB):
X 1 —(CY′═CZ′) n —(CY′Z′) n′ —O—C(═O)N(R 2 )R 3 (IB)
wherein X 1 is an optionally substituted aromatic group;
each Y′ and Z′ is independently hydrogen or a non-hydrogen substituent;
n and n′ are each positive integer; and
R 2 and R 3 are the same or different optionally substituted linear, branched or cyclic aliphatic group or an optionally substituted aromatic group,
wherein at least one of R 2 and R 3 is an optionally substituted branched alkyl group having 4 or more carbon atoms.
13. A positive-acting photoresist composition comprising:
(1) a resin comprising photoacid-labile groups;
(2) one or more acid generators; and
(3) a photobase generator that corresponds to the following Formula (IA):
X 1 —(CYZ) n —O—C(═O)N(R 2 )R 3 (IA)
wherein X 1 is an optionally substituted aromatic group, wherein the aromatic group is not substituted by a NO 2 group;
each Y and Z is independently hydrogen or a non-hydrogen substituent;
n is a positive integer; and
R 2 and R 3 are the same or different optionally substituted linear, branched or cyclic aliphatic group or an optionally substituted aromatic group,
wherein at least one of R 2 and R 3 is an optionally substituted branched alkyl group having 4 or more carbon atoms, and R 2 and R 3 are not substituted by a CO 2 H group or an ester group.
14. A method for forming a photolithographic pattern, comprising:
(a) applying a layer of a photoresist composition of claim 13 on a substrate;
(b) patternwise exposing the photoresist composition layer to activating radiation; and
(c) developing the exposed photoresist composition layer to provide a photoresist relief image.