Photoresist compositions and methods of forming photolithographic patterns
View Patent ↗Provided are photoresist compositions useful in forming photolithographic patterns by a negative tone development process. Also provided are methods of forming photolithographic patterns by a negative tone development process and substrates coated with the photoresist compositions. The compositions, methods and coated substrates find particular applicability in the manufacture of semiconductor devices.
1. A method of forming a photolithographic pattern, comprising:
(a) providing a substrate comprising one or more layer to be patterned over a surface of the substrate;
(b) applying a layer of a photoresist composition over the one or more layer to be patterned;
(c) patternwise exposing the photoresist composition layer to actinic radiation;
(d) heating the exposed photoresist composition layer in a post-exposure bake process; and
(e) applying a developer to the photoresist composition layer, wherein unexposed portions of the photoresist layer are removed by the developer, leaving a photoresist pattern over the one or more layer to be pattern;
wherein the photoresist composition comprises:
a first polymer which is acid sensitive;
a second polymer formed from a monomer having the following general formula (I):
wherein: P is a polymerizable functional group; Z is a spacer unit chosen from optionally substituted linear or branched aliphatic and aromatic hydrocarbons, and combinations thereof, optionally with one or more linking moiety chosen from —O—, —S—, —COO— and CONR 1 —, wherein R 1 is chosen from hydrogen and substituted and unsubstituted C1 to C10 linear, branched and cyclic hydrocarbons; n is an integer from 0 to 5; and R is chosen from substituted and unsubstituted C1 to C20 linear, branched and cyclic hydrocarbons;
wherein the second polymer is acid insensitive and free of fluorine and silicon, and wherein the second polymer has a surface energy lower than a surface energy of the first polymer;
a photoacid generator; and
a solvent.
2. The method of claim 1 , wherein P is a polymerizable backbone moiety having the following general structure:
wherein m is an integer from 0 to 3.
3. The method of claim 1 , wherein the patternwise exposing is conducted by immersion lithography.
4. The method of claim 1 , wherein the patternwise exposing is conducted by immersion lithography.
5. The method of claim 1 , wherein R is represented by the formula C n H 2n+1 , wherein n is an integer from 1 to 6.
6. The method of claim 1 , wherein P is a polymerizable functional group having the following general structure:
wherein R 2 is chosen from hydrogen and substituted and unsubstituted C1 to C3 alkyl; and X is oxygen or is represented by the formula NR 3 , wherein R 3 is chosen from hydrogen and substituted and unsubstituted C1 to C10 linear, branched and cyclic hydrocarbons.
7. The method of claim 6 , wherein the second polymer is formed from a monomer chosen from the following monomers:
wherein X is oxygen or is represented by the formula NR 3 , wherein R 3 is chosen from hydrogen and substituted and unsubstituted C1 to C10 linear, branched and cyclic hydrocarbons.
8. The method of claim 7 , wherein the second polymer is poly(n-butyl methacrylate.
9. The method of claim 1 , wherein the second polymer is formed from a monomer chosen from the following monomers:
10. The method of claim 1 , wherein P is a polymerizable backbone moiety having the following general structure:
wherein R 4 is chosen from hydrogen and substituted and unsubstituted C1 to C3 alkyl.
11. The method of claim 1 , wherein the first polymer comprises an acid-cleavable group.