Claims
- 1. A pattern formation material for electron beam lithography, comprising an alkali-soluble resin and a photoacid generator which generates an acid when irradiated with an electron beam, wherein
said pattern formation material further comprises first and second dissolution inhibiting groups each of which has a capacity of inhibiting dissolution of said alkali-soluble resin in an alkali solution and loses the capacity upon application of an acid, said first dissolution inhibiting group increasing a sensitivity of said pattern formation material when left to stand in a vacuum after irradiated with an electron beam, and said second dissolution inhibiting group decreasing the sensitivity of said pattern formation material when left to stand in a vacuum after irradiated with an electron beam, and a ratio of said first dissolution inhibiting group to said second dissolution inhibiting group is adjusted such that a size of an alkali-soluble portion, which is a portion made soluble in said alkali solution when said pattern formation material is irradiated with an electron beam, is substantially held constant independently of a standing time in a vacuum.
- 2. A material according to claim 1, wherein at least one of said first and second dissolution inhibiting groups is a functional group which modifies said alkali-soluble resin.
- 3. A material according to claim 1, wherein said pattern formation material further comprises a dissolution inhibitor, and at least one of said first and second dissolution inhibiting groups is a functional group which forms said dissolution inhibitor.
- 4. A material according to claim 1, wherein said first dissolution inhibiting group is a t-butoxycarbonyloxy group.
- 5. A material according to claim 1, wherein said second dissolution inhibiting group is an acetal-type functional group.
- 6. A material according to claim 1, wherein the ratio of said first dissolution inhibiting group to said second dissolution inhibiting group is adjusted such that a difference between the size of said alkali-soluble portion immediately after irradiated with an electron beam in a vacuum and the size of said alkali-soluble portion left to stand for 10 hr in a vacuum after irradiated with an electron beam is not more than ±5 nm.
- 7. A pattern formation method using a pattern formation material for electron beam lithography, said pattern formation material comprising an alkali-soluble resin and a photoacid generator which generates an acid when irradiated with an electron beam, said pattern formation material further comprising first and second dissolution inhibiting groups each of which has a capacity of inhibiting dissolution of said alkali-soluble resin in an alkali solution and loses the capacity upon application of an acid, said first dissolution inhibiting group increasing a sensitivity of said pattern formation material when left to stand in a vacuum after irradiated with an electron beam, and said second dissolution inhibiting group decreasing the sensitivity of said pattern formation material when left to stand in a vacuum after irradiated with an electron beam, comprising the steps of:
determining a ratio of said first dissolution inhibiting group to said second dissolution inhibiting group such that a size of an alkali-soluble portion, which is a portion made soluble in said alkali solution when said pattern formation material is irradiated with an electron beam, is substantially held constant independently of a standing time in a vacuum; forming a photosensitive film by coating a surface of an object to be processed with said pattern formation material containing said first and second dissolution inhibiting groups at the determined ratio; performing electron beam writing on said photosensitive film; and forming a patterned film by developing said photosensitive film subjected to the electron beam writing.
- 8. A method according to claim 7, further comprising the step of etching the surface of said object to be processed by using said patterned film as an etching mask.
- 9. A method according to claim 7, wherein at least one of said first and second dissolution inhibiting groups is a functional group which modifies said alkali-soluble resin.
- 10. A method according to claim 7, wherein said pattern formation material further comprises a dissolution inhibitor, and at least one of said first and second dissolution inhibiting groups is a functional group which forms said dissolution inhibitor.
- 11. A method according to claim 7, wherein said first dissolution inhibiting group is a t-butoxycarbonyloxy group.
- 12. A method according to claim 7, wherein said second dissolution inhibiting group is an acetal-type functional group.
- 13. A method according to claim 7, wherein the ratio of said first dissolution inhibiting group to said second dissolution inhibiting group is adjusted such that a difference between the size of said alkali-soluble portion immediately after irradiated with an electron beam in a vacuum and the size of said alkali-soluble portion left to stand for 10 hr in a vacuum after irradiated with an electron beam is not more than ±5 nm.
- 14. An exposure mask fabrication method using a pattern formation material for electron beam lithography, said pattern formation material comprising an alkali-soluble resin and a photoacid generator which generates an acid when irradiated with an electron beam, said pattern formation material further comprising first and second dissolution inhibiting groups each of which has a capacity of inhibiting dissolution of said alkali-soluble resin in an alkali solution and loses the capacity upon application of an acid, said first dissolution inhibiting group increasing a sensitivity of said pattern formation material when left to stand in a vacuum after irradiated with an electron beam, and said second dissolution inhibiting group decreasing the sensitivity of said pattern formation material when left to stand in a vacuum after irradiated with an electron beam, comprising the steps of:
determining a ratio of said first dissolution inhibiting group to said second dissolution inhibiting group such that a size of an alkali-soluble portion, which is a portion made soluble in said alkali solution when said pattern formation material is irradiated with an electron beam, is substantially held constant independently of a standing time in a vacuum; forming a light-shielding film on one principal surface of a transparent substrate; forming a photosensitive film by coating the surface of said light-shielding film with said pattern formation material containing said first and second dissolution inhibiting groups at the determined ratio; performing electron beam writing on said photosensitive film; forming a patterned film by developing said photosensitive film subjected to the electron beam writing; and etching said light-shielding film by using said patterned film as an etching mask.
- 15. A method according to claim 14, wherein at least one of said first and second dissolution inhibiting groups is a functional group which modifies said alkali-soluble resin.
- 16. A method according to claim 14, wherein said pattern formation material further comprises a dissolution inhibitor, and at least one of said first and second dissolution inhibiting groups is a functional group which forms said dissolution inhibitor.
- 17. A method according to claim 14, wherein said first dissolution inhibiting group is a t-butoxycarbonyloxy group.
- 18. A method according to claim 14, wherein said second dissolution inhibiting group is an acetal-type functional group.
- 19. A method according to claim 14, wherein the ratio of said first dissolution inhibiting group to said second dissolution inhibiting group is adjusted such that a difference between the size of said alkali-soluble portion immediately after irradiated with an electron beam in a vacuum and the size of said alkali-soluble portion left to stand for 10 hr in a vacuum after irradiated with an electron beam is not more than ±5 nm.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2000-080093 |
Mar 2000 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-080093, filed Mar. 22, 2000, the entire contents of which are incorporated herein by reference.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09812688 |
Mar 2001 |
US |
Child |
10665616 |
Sep 2003 |
US |