Pattern treatment methods
A pattern treatment method, comprising: (a) providing a semiconductor substrate comprising a patterned feature on a surface thereof; (b) applying a pattern treatment composition to the patterned feature, wherein the pattern treatment composition comprises: a block copolymer and an organic solvent, wherein the block copolymer comprises: (i) a first block comprising a first unit formed from 4-vinyl-pyridine, and (ii) a second block comprising a first unit formed from a vinyl aromatic monomer; and (c) removing residual pattern shrink composition from the substrate, leaving a coating of the block copolymer over the surface of the patterned feature, thereby providing a reduced pattern spacing as compared with a pattern spacing of the patterned feature prior to coating the pattern treatment composition. The methods find particular applicability in the manufacture of semiconductor devices for providing high resolution patterns.
1. A pattern treatment method, comprising:
(a) providing a semiconductor substrate comprising a patterned feature on a surface thereof;
(b) applying a pattern treatment composition to the patterned feature, wherein the pattern treatment composition comprises: a block copolymer and an organic solvent, wherein the block copolymer comprises: (i) a first block comprising a first unit formed from 4-vinyl-pyridine, and (ii) a second block comprising a first unit formed from a vinyl aromatic monomer; and
(c) removing residual pattern shrink composition from the substrate, leaving a coating of the block copolymer over the surface of the patterned feature, thereby providing a reduced pattern spacing as compared with a pattern spacing of the patterned feature prior to coating the pattern treatment composition.
2. The pattern treatment method of claim 1 , wherein the patterned feature is a photoresist pattern.
3. The pattern treatment method of claim 2 , wherein the photoresist pattern is formed by a negative tone development process comprising:
(a1) applying a layer of a photoresist composition over the semiconductor substrate, wherein the photoresist composition comprises: a resin comprising an acid cleavable leaving group, the cleavage of which forms an acid group and/or an alcohol group; a photoacid generator; and a solvent;
(a2) exposing the photoresist layer to activating radiation through a patterned photomask;
(a3) heating the photoresist layer, wherein acid generated by the acid generator causes cleavage of the acid cleavable leaving group, thereby forming the acid group and/or the alcohol group; and
(a4) developing the exposed photoresist composition layer with an organic solvent developer to form a negative photoresist pattern comprising an acid group and/or an alcohol group.
4. The pattern treatment method of claim 1 , wherein the vinyl aromatic monomer is of the following general formula (I):
wherein: R 1 is chosen from hydrogen and C1 to C3 alkyl or haloalkyl; and Ar 1 is chosen from optionally substituted aryl groups, optionally including one or more linking moiety chosen from —O—, —S—, —C(O)O— and —OC(O)—.
5. The pattern treatment method of claim 4 , wherein the vinyl aromatic monomer is styrene.
6. The pattern treatment method of claim 5 , wherein the block copolymer is poly(4-vinylpyridine)-b-polystyrene.
7. The pattern treatment method of claim 1 , wherein the vinyl aromatic monomer comprises fused aromatic rings.
8. The pattern treatment method of claim 1 , wherein all repeat units of the first block are formed from 4-vinylpyridine.
9. The pattern treatment method of claim 1 , wherein the second block further comprises a second unit formed from a monomer that is different from the vinyl aromatic monomer of the first unit.
10. The pattern treatment method of claim 1 , wherein the block copolymer further comprises a third block comprising a unit formed from a vinyl aromatic monomer.
11. The pattern treatment method of claim 1 , wherein the pattern treatment composition further comprises a second polymer that is different from the block copolymer.