Photoacid-generating copolymer and associated photoresist composition, coated substrate, and method of forming an electronic device
A copolymer include repeat units derived from an acid-labile monomer, an aliphatic lactone-containing monomer, a C 1-12 alkyl(meth)acrylate in which the C 1-12 alkyl group includes a specific base-soluble group, a photoacid-generating monomer that includes an aliphatic anion, and a neutral aromatic monomer having the formula wherein R 1 , R 2 , R 3 , X, m, and Ar are defined herein. The copolymer is used as a component of a photoresist composition. A coated substrate including a layer of the photoresist composition, and a method of forming an electronic device using the coated substrate are described.
1. A copolymer comprising repeat units derived from
an acid-labile monomer;
an aliphatic, lactone-containing monomer;
a base-soluble monomer comprising a 1,1,1,3,3,3-hexafluoro-2-hydroxyprop-2-yl substituent or a —NH—S(O) 2 —R b substituent wherein R b is C 1-4 perfluoroalkyl;
a photoacid-generating monomer comprising an aliphatic anion; and
a neutral aromatic monomer comprising
or a combination thereof, wherein R a is —H, —F, —CH 3 , or —CF 3 ; each occurrence of R c is independently halogen, C 1-6 perfluoroalkyl, or C 3-6 perfluorocycloalkyl; R d is C 1-10 alkyl, C 3-10 cycloalkyl, C 1-6 perfluoroalkyl, C 3-6 perfluorocycloalkyl, C 1-10 alkenyl, C 3-10 cycloalkenyl, or C 6-12 aryl; each occurrence of R e is independently C 1-10 alkylene or C 3-10 cycloalkylene; n is 1; and q is 1, 2, 3, 4, or 5;
wherein the repeat units are derived from monomers comprising no more than 55 mole percent of monomers comprising an aromatic group.
2. The copolymer of claim 1 , wherein the neutral aromatic monomer has a cLogP of 2.5 to 6.
3. The copolymer of claim 1 , wherein the acid-labile monomer comprises an unsubstituted or substituted tertiary hydrocarbyl(meth)acrylate comprising
or a combination thereof; wherein R a is —H, —F, —CH 3 , or —CF 3 .
4. The copolymer of claim 1 , wherein the base-soluble monomer comprises
or a combination thereof, wherein R a is —H, —F, —CH 3 , or —CF 3 ; and R b is C 1-4 perfluoroalkyl.
5. The copolymer of claim 1 , wherein the photoacid-generating monomer comprises
or a combination thereof, wherein R a is —H, —F, —CH 3 , or —CF 3 .
6. A photoresist composition comprising the copolymer of claim 1 .
7. 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 6 over the one or more layers to be patterned.
8. A method of forming an electronic device, comprising:
(a) applying a layer of a photoresist composition of claim 6 on a substrate;
(b) pattern-wise exposing the photoresist composition layer to extreme ultraviolet or electron beam activating radiation; and
(c) developing the exposed photoresist composition layer to provide a resist relief image.
9. The copolymer of claim 1 , wherein the photoacid-generating monomer comprises a cation having the structure
10. The copolymer of claim 9 , wherein the photoacid-generating monomer comprises an anion having the structure
wherein R a is —H, —F, —CH 3 , or —CF 3 .
11. A copolymer comprising repeat units derived from an acid-labile monomer comprising
an aliphatic, lactone-containing monomer comprising
a base-soluble monomer comprising
a photoacid-generating monomer comprising
a neutral aromatic monomer comprising
or a combination thereof, wherein R a is —H, —F, —CH 3 , or —CF 3 ; R c is halogen, C 1-12 hydrocarbyl, C 1-6 perfluoroalkyl, C 3-6 perfluorocycloalkyl; R d is C 1-10 alkyl, C 3-10 cycloalkyl, C 1-6 perfluoroalkyl, C 3-6 perfluorocycloalkyl, C 1-10 alkenyl, C 3-10 cycloalkenyl, or C 6-12 aryl; R e is C 1-10 alkylene or C 3-10 cycloalkylene; n is 0 or 1; and q is 0, 1, 2, 3, 4, or 5.