Photosensitive copolymer, photoresist comprising the copolymer, and articles formed therefrom

1. A copolymer comprising the polymerized product of:

an electron-sensitizing acid deprotectable monomer having the formula (XX) and a comonomer:

wherein R a is H, F, —CN, C 1-10 alkyl, or C 1-10 fluoroalkyl; and

wherein

R x and R y are each independently a substituted or unsubstituted C 1-10 alkyl group or C 3-10 cycloalkyl group, which together form a ring; and

R z is (i) a group comprising (a) a substituted or unsubstituted C 6-20 aromatic-containing group, (b) C 1-6 perfluoroalkyl or C 3-6 perfluorocycloalkyl attached to the C 6-20 aromatic-containing group, and (c) a C 1-10 alkylene group or a C 3-10 cycloalkylene group connecting the C 6-20 aromatic-containing group and the carbon atom to which substituents R x and R y are attached, or (ii) C 6-20 cycloaliphatic-containing group comprising C 3-6 perfluorocycloalkyl.

2. The copolymer of claim 1 , wherein R z comprises C 1-6 perfluoroalkyl.

3. The copolymer of claim 1 , wherein R z is a group comprising (a) a substituted or unsubstituted C 6-20 aromatic-containing group, (b) C 1-6 perfluoroalkyl attached to the C 6-20 aromatic-containing group, and (c) a C 1-10 alkylene group or a C 3-10 cycloalkylene group connecting the C 6-20 aromatic-containing group and the carbon atom to which substituents R x and R y are attached.

4. The copolymer of claim 1 , wherein the comonomer comprises at least one of the following monomers:

an acid-deprotectable monomer having the formula (V), a lactone-containing monomer of the formula (VI), a base-soluble monomer of formula (VII), a photoacid-generating monomer of the formula (VIII), or a combination comprising at least one of the foregoing monomers,

wherein

each R a is independently H, F, —CN, C 1-10 alkyl, or C 1-10 fluoroalkyl,

each R b is independently C 1-20 alkyl, C 3-20 cycloalkyl, C 6-20 aryl, or C 7-20 aralkyl, and each R b is separate or at least one R b is bonded to an adjacent R b to form a cyclic structure,

L is a monocyclic, polycyclic, or fused polycyclic C 4-20 lactone-containing group,

W is a halogenated or non-halogenated, aromatic or non-aromatic C 2-50 hydroxyl-containing organic group having a pKa of less than or equal to 12,

Q is ester-containing or non-ester containing and fluorinated or non-fluorinated and is C 1-20 alkylene, C 3-20 cycloalkylene, C 6-20 arylene, or C 7-20 aralkylene group,

A is ester-containing or non ester-containing and fluorinated or non-fluorinated, and is C 1-20 alkylene, C 3-20 cycloalkylene, C 6-20 arylene, or C 7-20 aralkylene,

Z − is an anionic moiety comprising sulfonate, an anion of a sulfonamide, or an anion of a sulfonimide, and

G + is a sulfonium or iodonium cation.

5. The copolymer of claim 4 , wherein the comonomer comprises the photoacid-generating monomer of the formula (VIII).

6. A photoresist composition comprising the copolymer of claim 1 .

7. The photoresist composition of claim 6 , further comprising a photoacid generator.

8. A method of forming an electronic device, comprising: (a) applying a layer of a photoresist composition of claim 6 on a substrate; (b) patternwise exposing the photoresist composition layer to activating radiation; (c) developing the exposed photoresist composition layer to provide a resist relief image, and (d) etching the resist relief pattern into the underlying substrate.

9. The method of claim 8 , wherein the radiation is extreme-ultraviolet or e-beam radiation.

10. A copolymer comprising the polymerized product of an electron-sensitizing acid deprotectable monomer having the formula:

or a combination thereof, and a comonomer.

11. A copolymer comprising the polymerized product of:

an electron-sensitizing acid deprotectable monomer having the formula (III) or (IV) and a comonomer:

wherein each R a is independently H, F, —CN, CH 3 , or CF 3 ,

R c is C 1-10 alkyl or C 3-10 cycloalkyl,

R d , R e , R f , and R g are independently C 1-6 perfluoroalkyl or C 3-6 perfluorocycloalkyl,

S 2 is a C 1-10 alkylene group, or a C 3-10 cycloalkylene group,

x is an integer of from 1 to 20, y is an integer of from 1 to 20,

m is an integer of from 0 to 5, n is an integer of from 1 to 5, and

p is an integer of from 0 to 2x+6.