Photolithographic methods

1. A method of forming an electronic device, comprising in sequence:

(a) providing a semiconductor substrate comprising one or more layers to be patterned;

(b) forming a photoresist layer over the one or more layers to be patterned, wherein the photoresist layer is formed from a composition that comprises: a matrix polymer comprising a unit having an acid labile group; a photoacid generator; and an organic solvent;

(c) coating a photoresist overcoat composition over the photoresist layer, wherein the overcoat composition comprises a quenching polymer and an organic solvent, wherein the quenching polymer consists essentially of a first repeating unit having a basic moiety effective to neutralize acid generated by the photoacid generator in a surface region of photoresist layer, and a second repeating unit formed from a monomer of the following general formula (I):

 wherein: R 1 is chosen from hydrogen and substituted or unsubstituted C1 to C3 alkyl; R 2 is chosen from substituted and unsubstituted C1 to C15 alkyl and is free of fluoroalkyl and fluoroalcohol; X is oxygen, sulfur or is represented by the formula NR 3 , wherein R 3 is chosen from hydrogen and substituted and unsubstituted C1 to C10 alkyl; and Z is a single bond or a spacer unit chosen from optionally substituted aliphatic and aromatic hydrocarbons, and combinations thereof, optionally with one or more linking moiety chosen from —O—, —S—, —COO—and —CONR 4 —wherein R 4 is chosen from hydrogen and substituted and unsubstituted C1 to C10 alkyl and wherein the quenching polymer repeating units consist of the first repeating unit and the second repeating unit;

(d) exposing the photoresist layer to activating radiation;

(e) heating the substrate in a post-exposure bake process; and

(f) developing the exposed photoresist layer with an organic solvent developer.

2. The method of claim 1 , wherein the first repeating unit having the basic moiety is formed from a monomer chosen from one or more of the following:

3. The method of claim 2 , wherein the first repeating unit having the basic moiety is formed from a monomer chosen from one or more of the following:

4. The method of claim 1 , wherein the first repeating unit having the basic moiety is present in the polymer in an amount of from 0.1 to 30 mol % based on the quenching polymer.

5. The method of claim 1 , wherein the monomer of general formula (I) is a monomer of the following general formula (II):

wherein R 5 , R 6 , and R 7 independently represent hydrogen or a C 1 to C 3 alkyl.

6. The method of claim 1 , wherein Z is a single bond.

7. The method of claim 1 , wherein the quenching polymer is a random copolymer.

8. The method of claim 1 , wherein the quenching polymer is a block copolymer.

9. The method of claim 1 , wherein the quenching polymer is a gradient copolymer.

10. The method of claim 1 , wherein the photoresist overcoat composition is free of acid generator compounds.

11. A method of forming an electronic device, comprising in sequence:

(a) providing a semiconductor substrate comprising one or more layers to be patterned;

(b) forming a photoresist layer over the one or more layers to be patterned, wherein the photoresist layer is formed from a composition that comprises: a matrix polymer comprising a unit having an acid labile group; a photoacid generator; and an organic solvent;

(c) coating a photoresist overcoat composition over the photoresist layer, wherein the overcoat composition comprises a quenching polymer and an organic solvent, wherein the quenching polymer consists essentially of: a first repeating unit having a basic moiety effective to neutralize acid generated by the photoacid generator in a surface region of photoresist layer; and a second repeating unit formed from a monomer of the following general formula (I):

 wherein: R 1 is chosen from hydrogen and substituted or unsubstituted C1 to C3 alkyl; R 2 is chosen from C1 to C15 unsubstituted alkyl; X is oxygen, sulfur or is represented by the formula NR 3 , wherein R 3 is chosen from hydrogen and substituted and unsubstituted C1 to C10 alkyl; and Z is a single bond or a spacer unit chosen from optionally substituted aliphatic and aromatic hydrocarbons, and combinations thereof, optionally with one or more linking moiety chosen from —O—, —S—, —COO—and —CONR 4 —wherein R 4 is chosen from hydrogen and substituted and unsubstituted C1 to C10 alkyl; and all quenching polymer repeating units are chosen from the first repeating units having a basic moiety and the second repeating units formed from a monomer of general formula (I);

(d) exposing the photoresist layer to activating radiation;

(e) heating the substrate in a post-exposure bake process;

(f) developing the exposed photoresist layer with an organic solvent developer; and

(g) etching the one or more layers using the developed photoresist layer as a mask.

12. The method of claim 11 , wherein the first repeating unit having the basic moiety is formed from a monomer chosen from one or more of the following:

13. The method of claim 11 , wherein the first repeating unit having the basic moiety is present in the polymer in an amount of from 0.1 to 30 mol % based on the quenching polymer.

14. The method of claim 11 , wherein Z is a single bond.