Method of forming resist pattern
View Patent ↗A method of forming a resist pattern effectively controls the manner/style and the amount of modification of a resist pattern in its reflowing process, realizing a desired resist pattern with a desired accuracy even if the deformation amount of the resist pattern is increased in the reflowing process. A second layer is formed on a first layer and then, a first resist pattern is formed on the second layer. The second layer is selectively etched using the first resist pattern as a mask. Thereafter, wettability of at least part of an exposed area of the second or first layer from the first resist pattern is adjusted, thereby forming a wettability-adjusted part. The first resist pattern is modified in such a way as to extend to the wettability-adjusted area by reflowing the first resist pattern using an organic solvent, thereby forming a second resist pattern for selectively etching the first layer or the second layer.
1. A method of forming a resist pattern, comprising:
forming a second layer on a first layer;
forming an initial resist pattern on the second layer;
adjusting a wettability of a desired exposed area of the second layer and/or the first layer, thereby forming a wettability-adjusted area; and
modifying the initial resist pattern in such a way as to extend to the wettability-adjusted area by reflowing the initial resist pattern using an organic solvent, thereby forming a modified resist pattern.
2. The method according to claim 1 , wherein the wettability-adjusted area includes a first sub-area having an increased wettability and a second sub-area having a decreased wettability.
3. The method according to claim 2 , wherein the wettability increase of the first sub-area and the wettability decrease of the second sub-area are generated according to their underlying layers or materials.
4. The method according to claim 2 , wherein the first sub-area is located in a place where a desired deformation of the initial resist pattern is relatively large and the second sub-area is located in a place where a desired deformation of the initial resist pattern is relatively small.
5. The method according to claim 1 , wherein the step of adjusting a wettability of the desired exposed area is carried out by a plasma treatment.
6. The method according to claim 5 , wherein a mixture of CHF 3 and O 2 is used as a gas for wettability adjustment in the plasma treatment.
7. The method according to claim 5 , wherein the plasma treatment is carried out in a first step where CHF 3 is used as a gas for wettability adjustment and in a second step where O 2 is used as a gas for wettability adjustment.
8. The method according to claim 1 , wherein the step of modifying the initial resist pattern is carried out by exposing the initial resist pattern to a vapor of the organic solvent to thereby penetrate the solvent into the initial resist pattern.
9. The method according to claim 1 , wherein the step of modifying the initial resist pattern is carried out by immersing the initial resist pattern into the organic solvent to thereby penetrate the solvent into the initial resist pattern.
10. The method according to claim 1 , wherein at least one of alcohols, ethers, esters, ketones, and glycol ethers is used as the organic solvent.
11. A method of forming a resist pattern, comprising:
forming an initial resist pattern on a layer or material;
adjusting a wettability of a desired exposed area of the layer or material, thereby forming a wettability-adjusted area; and
reflowing the initial resist pattern by penetration of an organic solvent in such a way as to expand to the wettability-adjusted area, thereby forming a modified resist pattern.
12. The method according to claim 11 , wherein the wettability-adjusted area includes a first sub-area having an increased wettability and a second sub-area having a decreased wettability.
13. The method according to claim 12 , wherein the wettability increase of the first sub-area and the wettability decrease of the second sub-area are generated according to their underlying layers or materials.
14. The method according to claim 12 , wherein the first sub-area is located in a place where a desired deformation of the initial resist pattern is relatively large and the second sub-area is located in a place where a desired deformation of the initial resist pattern is relatively small.
15. The method according to claim 11 , wherein the step of adjusting a wettability of the desired exposed area is carried out by a plasma treatment.
16. The method according to claim 15 , wherein a mixture of CHF 3 and O 2 is used as a gas for wettability adjustment in the plasma treatment.
17. The method according to claim 15 , wherein the plasma treatment is carried out in a first step where CHF 3 is used as a gas for wettability adjustment and in a second step where O 2 is used as a gas for wettability adjustment.
18. The method according to claim 11 , wherein the step of reflowing the initial resist pattern is carried out by exposing the initial resist pattern to a vapor of the organic solvent to thereby penetrate the solvent into the initial resist pattern.
19. The method according to claim 11 , wherein the step of reflowing the initial resist pattern is carried out by immersing the initial resist pattern into the organic solvent to thereby penetrate the solvent into the initial resist pattern.
20. The method according to claim 11 , wherein at least one of alcohols, ethers, esters, ketones, and glycol ethers is used as the organic solvent.