Photoresist pattern trimming compositions and methods

1. A photoresist pattern trimming composition, comprising:

a matrix polymer comprising a unit formed from a monomer of the following general formula (I):

wherein: R 1 is chosen from hydrogen, fluorine, C 1 -C 3 alkyl and C 1 -C 3 fluoroalkyl; R 2 is chosen from C 1 -C 15 alkylene; and R 3 is chosen from C 1 -C 3 fluoroalkyl;

an aromatic acid that is free of fluorine; and

a solvent.

2. The photoresist pattern trimming composition of claim 1 , wherein the matrix polymer comprises a further unit comprising a fluoroalcohol group.

3. The photoresist pattern trimming composition of claim 2 , wherein the matrix polymer comprises a further unit comprising a sulfonic acid group.

4. The photoresist pattern trimming composition of claim 1 , wherein the matrix polymer comprises a further unit comprising a sulfonic acid group.

5. The photoresist pattern trimming composition of claim 1 , wherein the aromatic acid comprises an acid of the general formula (I):

wherein: R 1 independently represents a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C5-C20 aryl group or a combination thereof, optionally containing one or more group chosen from carbonyl, carbonyloxy, sulfonamido, ether, thioether, a substituted or unsubstituted alkylene group, or a combination thereof; Z 1 independently represents a group chosen from carboxyl, hydroxy, nitro, cyano, C1 to C5 alkoxy, formyl and sulfonic acid; a and b are independently an integer from 0 to 5; and a+b is 5 or less.

6. A method of trimming a photoresist pattern, comprising:

(a) providing a semiconductor substrate;

(b) forming a photoresist pattern on the substrate, wherein the photoresist pattern is formed from a chemically amplified photoresist composition comprising: a matrix polymer comprising an acid labile group; a photoacid generator; and a solvent;

(c) coating a photoresist trimming composition of any one of claims 1 to 5 on the substrate over the photoresist pattern;

(d) heating the coated substrate, thereby causing a change in polarity of the photoresist matrix polymer in a surface region of the photoresist pattern; and

(e) contacting the photoresist pattern with a rinsing agent to remove the surface region of the photoresist pattern, thereby forming a trimmed photoresist pattern.

7. The method of claim 6 , wherein the solvent of the trimming composition comprises an organic solvent.

8. The method of claim 6 , wherein the trimming composition is an aqueous solution.

9. The method of claim 6 , wherein the rinsing agent comprises water or an aqueous alkaline solution.

10. The method of claim 6 , wherein the rinsing agent comprises an organic solvent or solvent mixture.

11. The photoresist pattern trimming composition of claim 1 , wherein the monomer of general formula (I) is chosen from the following monomers:

12. The photoresist pattern trimming composition of claim 2 , wherein the fluoroalcohol group is a hexafluoroalcohol group.

13. The photoresist pattern trimming composition of claim 2 , wherein the unit comprising the fluoroalcohol group formed from a monomer represented by the following general formula (II):

wherein: R 4 is chosen from hydrogen, fluorine, C 1 -C 3 alkyl and C 1 -C 3 fluoroalkyl; R 5 is an n+1 valent group chosen from C 1 -C 15 alkylene, and may be straight-chained, branched, cyclic or a combination thereof; and R f 's are independently chosen from C 1 -C 3 fluoroalkyl, and may be straight-chained or branched; and n is an integer from 1 to 4.

14. The photoresist pattern trimming composition of claim 13 , wherein the monomer of general formula (II) is chosen from the following monomers:

15. The photoresist pattern trimming composition of claim 1 , wherein the unit comprising the sulfonic acid group is chosen from the following monomers:

16. The photoresist pattern trimming composition of claim 1 , wherein the matrix polymer is made up only of poly(meth)acrylate and/or poly(meth)acrylamide units.

17. The photoresist pattern trimming composition of claim 1 , further comprising one or more additional polymer.

18. The photoresist pattern trimming composition of claim 1 , wherein the aromatic acid is chosen from the following acids: