Photoacid generator, photoresist, coated substrate, and method of forming an electronic device
View Patent ↗A photoacid generator compound has formula (1) wherein n is zero or 1; and R 1 -R 6 are each independently hydrogen, halogen, or unsubstituted or substituted C 1-20 linear or branched alkyl, C 1-20 cycloalkyl, C 6-20 aryl, C 3-20 heteroaryl, or an acid-generating group having the structure * L-Z − M + ] wherein L is an unsubstituted or substituted C 1-50 divalent group; Z − is a monovalent anionic group; and M + is an iodonium or sulfonium cation. Geminal R groups can combine to form a ring with the carbon to which they are attached, as long as no more than two such rings are formed. At least one of R 1 -R 6 includes the acid-generating group or two germinal R groups combine to form the acid-generating group. Also described are a photoresist composition incorporating the photoacid generator compound, a coated substrate including a layer of the photoresist composition, and a method of forming an electronic device using a layer of the photoresist composition.
1. A photoacid generator compound having the formula (1)
wherein
n is zero or 1; and
R 1 and R 2 are each independently halogen, unsubstituted or substituted C 1-20 linear or branched alkyl, unsubstituted or substituted C 1-20 cycloalkyl, unsubstituted or substituted C 6-20 aryl, unsubstituted or substituted C 3-20 heteroaryl, or a monovalent group having the structure
* L-Z − M + ]
wherein L is an unsubstituted or substituted C 1-50 divalent group; Z − is a monovalent anionic group selected from carboxylate, sulfate, sulfonate, sulfamate, sulfonamidate, and sulfonimidate; and M + is a cation selected from disubstituted iodonium ions and trisubstituted sulfonium ions; wherein R′ and R 2 can be taken together to form a ring;
R 3 , R 4 , R 5 , and R 6 are each independently hydrogen, halogen, unsubstituted or substituted C 1-20 linear or branched alkyl, unsubstituted or substituted C 1-20 cycloalkyl, unsubstituted or substituted C 6-20 aryl, unsubstituted or substituted C 3-20 heteroaryl, or a monovalent group having the structure
* L-Z − M + ]
wherein L is an unsubstituted or substituted C 1-50 divalent group; Z − is a monovalent anionic group selected from carboxylate, sulfate, sulfonate, sulfamate, sulfonamidate, and sulfonimidate; and M + is a cation selected from disubstituted iodonium ions and trisubstituted sulfonium ions; wherein
R 3 and R 4 can be taken together to form a ring and/or
R 5 and R 6 can be taken together to form a ring,
provided that no more than two rings are collectively formed by R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 , and
provided that one of R′, R 2 , R 3 , R 4 , R 5 , and R 6 has the structure
* L-Z − M + ], or
R 1 and R 2 are taken together to form
* L-Z − M + ], or
R 3 and R 4 are taken together to form
* L-Z − M + ], or
R 5 and R 6 are taken together to form
* L-Z − M + ].
2. The photoacid generator compound of claim 1 , having the formula (2a)
wherein
R 3 or R 4 is
* L-SO 3 − M + ], or
R 3 and R 4 are taken together to form
*♭L-SO 3 − M + ]; and
R′, R 2 , L, and M + are as defined in claim 1 .
3. The photoacid generator compound of claim 2 , wherein L is a substituted C 1-50 divalent group, L′, having the formula (3)
wherein
m is zero or 1,
Y is an unsubstituted or substituted C 1-20 alkylene,
W 1 is an unsubstituted or substituted divalent C 5-20 alicyclic group,
X is an unsubstituted or substituted C 1-20 alkylene, and
R 7 and R 8 are each independently fluorine, or partially fluorinated C 1-12 alkyl, or perfluorinated C 1-12 alkyl.
4. The photoacid generator compound of claim 3 , wherein m is 1.
5. The photoacid generator compound of claim 1 , having the formula (2b)
wherein
R 1 or R 2 is
* L-SO 3 − M + ], or
R 1 and R 2 are taken together to form
* L-SO 3 − M + ]; and
R 3 , R 4 , L, and M + are as defined in claim 1 .
6. The photoacid generator compound of claim 1 , comprising
or a combination thereof; wherein M + is as defined in claim 1 .
7. A photoresist composition comprising:
an acid-sensitive polymer, and
the photoacid generator compound of claim 1 .
8. A coated substrate comprising:
(a) a substrate having one or more layers to be patterned on a surface thereof; and
(b) a layer of the photoresist composition of claim 7 over the one or more layers to be patterned.
9. A method of forming an electronic device, comprising:
(a) applying a layer of a photoresist composition of claim 7 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 method of claim 9 , wherein the activating radiation is extreme ultraviolet (EUV) or electron-beam radiation.
11. The method of claim 9 , wherein the photoacid generator compound has the formula (2a)
wherein
R 3 or R 4 is
* L-SO 3 − M + ], or
R 3 and R 4 are taken together to form
* L-SO 3 − M + ]; and
R 1 , R 2 , L, and M + are as defined in claim 1 .
12. The method of claim 11 , wherein L is a substituted C 1-50 divalent group, L 1 , having the formula (3)
wherein
m is zero or 1,
Y is an unsubstituted or substituted C 1-20 alkylene,
W 1 is an unsubstituted or substituted divalent C 5-20 alicyclic group,
X is an unsubstituted or substituted C 1-20 alkylene, and
R 7 and R 8 are each independently fluorine, or partially fluorinated C 1-12 alkyl, or perfluorinated C 1-12 alkyl.
13. The method of claim 12 , wherein m is 1.
14. The method of claim 9 , wherein the photoacid generator compound has the formula (2b)
wherein
R 1 or R 2 is
* L-SO 3 − M + ], or
R 1 and R 2 are taken together to form
* L-SO 3 − M + ]; and
R 3 , R 4 , L, and M + are as defined in claim 1 .
15. The photoresist composition of claim 7 , wherein the photoacid generator compound has the formula (2a)
wherein
R 3 or R 4 is
*♭L-SO 3 − M + ], or
R 3 and R 4 are taken together to form
* L-SO 3 − M + ]; and
R 1 , R 2 , L, and M + are as defined in claim 1 .
16. The photoresist composition of claim 15 , wherein L is a substituted C 1-50 divalent group, L 1 , having the formula (3)
wherein
m is zero or 1,
Y is an unsubstituted or substituted C 1-20 alkylene,
W 1 is an unsubstituted or substituted divalent C 5-20 alicyclic group,
X is an unsubstituted or substituted C 1-20 alkylene, and
R 7 and R 8 are each independently fluorine, or partially fluorinated C 1-12 alkyl, or perfluorinated C 1-12 alkyl.
17. The photoresist composition of claim 16 , wherein m is 1.
18. The photoresist composition of claim 7 , wherein the photoacid generator compound has the formula (2b)
wherein
R 1 or R 2 is
* L-SO 3 − M + ], or
R 1 and R 2 are taken together to form
* L-SO 3 − M + ]; and
R 3 , R 4 , L, and M + are as defined in claim 1 .
19. A photoacid generator compound having the formula (2b)
wherein
R 1 is
* L-SO 3 − M + ],
wherein L is a substituted C 1-50 divalent group, L 2 , having the structure
wherein X is an unsubstituted or substituted C 1-20 alkylene; R 7 and R 8 are each independently fluorine, or partially fluorinated C 1-12 alkyl, or perfluorinated C 1-12 alkyl; and M + is a cation selected from disubstituted iodonium ions and trisubstituted sulfonium ions;
R 2 and R 3 are hydrogen;
R 4 has the structure
wherein m is zero or 1, Y is an unsubstituted or substituted C 1-20 alkylene, and W 2 is an unsubstituted or substituted monovalent C 5-20 alicyclic group.