Photoresist compositions and pattern formation methods
A photoresist composition, comprising an acid-sensitive polymer comprising a repeating unit having an acid-labile group; an iodonium salt comprising an anion and a cation, the iodonium salt having Formula (1): wherein Z − is an organic anion; Ar 1 is substituted or unsubstituted C 4-60 heteroaryl group comprising a furan heterocycle; and R 1 is substituted or unsubstituted hydrocarbon group as provided herein, wherein the cation optionally comprises an acid-labile group, wherein Ar 1 and R 1 are optionally connected to each other via a single bond or one or more divalent linking groups to form a ring, and wherein the iodonium salt is optionally covalently bonded through Ar 1 or substituent thereof as a pendant group to a polymer, the iodonium salt is optionally covalently bonded through R 1 or substituent thereof as a pendant group to a polymer, or the iodonium salt is optionally covalently bonded through Z − as a pendant group to a polymer; and a solvent.
1. A photoresist composition, comprising:
an acid-sensitive polymer comprising a repeating unit having an acid-labile group;
an iodonium salt comprising an anion and a cation, wherein the cation comprises one, and not more than one, iodonium cation, the iodonium salt having Formula (1):
wherein,
Z − is an organic anion comprising a group chosen from sulfonate, a methide anion, an anion of a sulfonamide, an anion of a sulfonimide, a sulfamate, a phenolate, or carboxylate;
Ar 1 is a substituted or unsubstituted C 4-60 heteroaryl group comprising a furan heterocycle; and
R 1 is a C 1-20 alkyl group, a C 1-20 heteroalkyl group, a C 3-20 cycloalkyl group, a C 2-20 heterocycloalkyl group, a C 2-20 alkenyl group, a C 2-20 heteroalkenyl group, a C 6-30 aryl group, a C 4-30 heteroaryl group, a C 7-20 arylalkyl group, or a C 4-20 heteroarylalkyl group, each of which is substituted or unsubstituted,
wherein the cation optionally comprises an acid-labile group,
wherein Ar 1 and R 1 are optionally connected to each other via a single bond or one or more divalent linking groups to form a ring, and
wherein the iodonium salt is optionally covalently bonded through Ar 1 or through a substituent thereof as a pendant group to a polymer, the iodonium salt is optionally covalently bonded through R 1 or through a substituent thereof as a pendant group to a polymer, or the iodonium salt is optionally covalently bonded through Z − as a pendant group to a polymer; and
a solvent.
2. The photoresist composition of claim 1 , wherein Ar 1 and R 1 are connected to each other via a single bond or a divalent linking group to form a ring.
3. The photoresist composition of claim 1 , wherein Ar 1 is substituted with an acid-labile group, R 1 is substituted with an acid-labile group, or both Ar 1 and R 1 are each independently substituted with an acid-labile group.
4. The photoresist composition of claim 1 , further comprising a photoacid generator, wherein the corresponding photoacid of the photoacid generator has a lower pKa than a corresponding photoacid of the iodonium salt. .
5. The photoresist composition of claim 1 , further comprising a photo-decomposable quencher, wherein the corresponding photoacid of the photo-decomposable quencher has a higher pKa than a corresponding photoacid of the iodonium salt.
6. The photoresist composition of claim 1 , wherein the acid- sensitive polymer comprises a repeating unit having an aromatic group, wherein the aromatic group is substituted or unsubstituted.
7. The photoresist composition of claim 1 , wherein the C 4-60 heteroaryl group is
wherein,
R 6a , R 6b , R 6c , R 6d , R 6e , and R 6f are each independently a single bond, hydrogen, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 haloalkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 1-30 heterocycloalkyl, substituted or unsubstituted C 2-30 alkenyl, substituted or unsubstituted C 2-30 alkynyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 7-30 arylalkyl, substituted or unsubstituted C 7-30 alkylaryl, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 heteroarylalkyl, halogen, —OR 61 , —SR 62 , or —NR 63 R 64 , wherein R 61 to R 64 are each independently hydrogen, or substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 2-30 heterocycloalkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 7-30 arylalkyl, substituted or unsubstituted C 3-30 heteroaryl, or substituted or unsubstituted C 4-30 heteroarylalkyl;
one of R 6a , R 6b , R 6c , R 6d , R 6e , or R 6f is a single bond to the iodonium cation;
m is 0 to 6;
n is 0 to 6; and
x is 1 to 6.
8. The photoresist composition of claim 1 , wherein the iodonium salt is covalently bonded as a pendant group to a polymer.
9. A pattern formation method, comprising:
(a) applying a layer of a photoresist composition of claim 1 on a substrate;
(b) pattern-wise exposing the photoresist composition layer to activating radiation; and
(c) developing the exposed photoresist composition layer to provide a resist relief image.
10. The pattern formation method of claim 9 , wherein the activating radiation is extreme ultraviolet radiation at a wavelength of 13.5 nanometers.
11. The pattern formation method of claim 9 , wherein in the iodonium salt having Formula (1), Ar 1 and R 1 are connected to each other via a single bond or a divalent linking group to form a ring.
12. The pattern formation method of claim 9 , wherein in the iodonium salt having Formula (1), Ar 1 is substituted with an acid-labile group, R 1 is substituted with an acid-labile group, or both Ar 1 and R 1 are each independently substituted with an acid-labile group.
13. The pattern formation method of claim 9 , wherein the photoresist composition further comprises a photoacid generator, wherein the corresponding photoacid of the photoacid generator has a lower pKa than a corresponding photoacid of the iodonium salt.
14. The pattern formation method of claim 9 , wherein the photoresist composition further comprises a photo-decomposable quencher, wherein the corresponding photoacid of the photo-decomposable quencher has a higher pKa than a corresponding photoacid of the iodonium salt.
15. The pattern formation method of claim 9 , wherein in the photoresist composition, the acid-sensitive polymer comprises a repeating unit having an aromatic group, wherein the aromatic group is substituted or unsubstituted.
16. The pattern formation method of claim 9 , wherein in the iodonium salt having Formula (1), the C 4-60 heteroaryl group is
wherein,
R 6a , R 6b , R 6c , R 6d , R 6e , and R 6f are each independently a single bond, hydrogen, substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 1-30 haloalkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 1-30 heterocycloalkyl, substituted or unsubstituted C 2-30 alkenyl, substituted or unsubstituted C 2-30 alkynyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 7-30 arylalkyl, substituted or unsubstituted C 7-30 alkylaryl, substituted or unsubstituted C 3-30 heteroaryl, substituted or unsubstituted C 4-30 heteroarylalkyl, halogen, −OR 61 , −SR 62 , or −NR 63 R 64 , wherein R 61 to R 64 are each independently hydrogen, or substituted or unsubstituted C 1-30 alkyl, substituted or unsubstituted C 3-30 cycloalkyl, substituted or unsubstituted C 2-30 heterocycloalkyl, substituted or unsubstituted C 6-30 aryl, substituted or unsubstituted C 7-30 arylalkyl, substituted or unsubstituted C 3-30 heteroaryl, or substituted or unsubstituted C 4-30 heteroarylalkyl;
one of R 6a ,R 6b , R 6c , R 6d , R 6e , or R 6f is a single bond to the iodonium cation;
m is 0 to 6;
n is 0 to 6; and
x is 1 to 6.
17. The pattern formation method of claim 9 , wherein in the photoresist composition, the iodonium salt is covalently bonded as a pendant group to a polymer.