Photoresist overcoat compositions and methods of forming electronic devices
View Patent ↗Provided are photoresist overcoat compositions, substrates coated with the overcoat compositions and methods of forming electronic devices by a negative tone development process. The compositions, coated substrates and methods find particular applicability in the manufacture of semiconductor devices.
1. A photoresist overcoat composition, comprising:
a first polymer comprising as polymerized units 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; 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; wherein the first polymer is free of fluorine;
a second polymer comprising as polymerized units a monomer of the general formula (I);
an organic solvent; and
a basic quencher.
2. The photoresist overcoat composition of claim 1 , wherein the first polymer contains as polymerized units 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 group.
3. The photoresist overcoat composition of claim 2 , wherein Z is a single bond.
4. The photoresist overcoat composition of claim 1 , wherein the organic solvent comprises an alkyl butyrate.
5. The photoresist overcoat composition of claim 1 , wherein the organic solvent comprises an alkyl propionate.
6. The photoresist overcoat composition of claim 1 , wherein the organic solvent comprises a branched ketone.
7. The photoresist overcoat composition of claim 1 , wherein the organic solvent comprises a C 8 -C 9 alkyl butyrate, a C 8 -C 9 alkyl propionate, a C 8 -C 9 ketone or a combination thereof.
8. The photoresist overcoat composition of claim 1 , wherein the basic quencher is present in an amount of from 0.1 to 5 wt % based on total solids of the photoresist overcoat composition.
9. A coated substrate, comprising a substrate, a photoresist layer over the substrate and a layer of the photoresist overcoat composition of claim 1 over the photoresist layer.
10. A method of forming an electronic device, comprising:
(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;
(c) forming an overcoat layer over the photoresist layer from the overcoat composition of claim 1 ;
(d) exposing the overcoat-coated photoresist layer to actinic radiation; and
(e) developing the overcoat-coated photoresist layer with an organic solvent developer.
11. The method of claim 10 , wherein the organic solvent developer comprises 2-heptanone.
12. The method of claim 10 , wherein the organic solvent comprises n-butyl acetate.
13. The photoresist overcoat composition of claim 1 , wherein R 2 is straight chained or branched.
14. The photoresist overcoat composition of claim 1 , wherein R 2 is a C4 to C8 alkyl.
15. The photoresist overcoat composition of claim 1 , wherein the basic quencher is a non-surfactant.
16. A photoresist overcoat composition, comprising:
a first polymer comprising as polymerized units 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; 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;
a second polymer comprising as polymerized units a monomer of the general formula (I);
an organic solvent; and
a basic quencher, wherein the basic quencher has a higher surface free energy than the first and second polymers.
17. The photoresist overcoat composition of claim 1 , wherein the basic quencher is chosen from cyclic aliphatic amines.
18. The photoresist overcoat composition of claim 1 , wherein the basic quencher is chosen from aliphatic amines.