Developer compositions and methods of forming photolithographic patterns
Provided are photoresist developer compositions that include a mixture of organic solvents. Also provided are methods of forming photolithographic patterns using negative tone development, coated substrates and electronic devices formed by the methods. The methods find particular applicability in the manufacture of electronic 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 photoresist developer composition to the post-exposure baked photoresist composition layer to remove unexposed regions of the photoresist composition layer, thereby forming a photoresist pattern, wherein the photoresist developer composition comprises a mixture of a first organic solvent and a second organic solvent that are different from each other, wherein the first organic solvent is 2-heptanone and the second organic solvent is n-butyl propionate.
2. The method of claim 1 , further comprising performing a second patternwise exposure of the photoresist composition layer to actinic radiation after the patternwise exposure and before applying the photoresist developer composition.
3. The method of claim 1 , further comprising after (e):
(f) transferring the pattern of the photoresist pattern to one or more layer underlying the photoresist pattern by an etching process;
(g) forming one or more additional layer to be patterned over the surface of the substrate;
(h) applying a second layer of a photoresist composition over the one or more additional layer to be patterned;
(i) patternwise exposing the second photoresist composition layer to actinic radiation;
(j) heating the exposed second photoresist composition layer in a post-exposure bake process; and
(h) applying a second photoresist developer composition to the post-exposure baked second photoresist composition layer to remove unexposed regions of the second photoresist composition layer, thereby forming a second photoresist pattern, wherein the second photoresist developer composition comprises the same first organic solvent and second organic solvent as the first photoresist developer composition.
4. The method of claim 3 , wherein the ratio of the first organic solvent to the second organic solvent in the first photoresist developer is different from the ratio of the first organic solvent to the second organic solvent in the second photoresist developer.
5. The method of claim 1 , wherein the first organic solvent is present in the composition in an amount of from 30 to 70 wt % based on the total developer composition, and the second organic developer is present in the composition in an amount of from 70 to 30 wt % based on the total developer composition.