Apparatus and method for conformal mask manufacturing
A manufacturing process technology creates a pattern on a first layer using a focused ion beam process. The pattern is transferred to a second layer, which may act as a traditional etch stop layer. The pattern can be formed on the second layer without irradiation by light through a reticle and without wet chemical developing, thereby enabling conformal coverage and very fine critical feature control. Both dark field patterns and light field patterns are disclosed, which may enable reduced or minimal exposure by the focused ion beam.
1. A method for processing comprising:
providing a workpiece comprising a particle beam patternable layer that is configured to be first removed through interaction with a particle beam and a transfer layer thereunder; and
exposing regions of the particle beam patternable layer using a focused particle beam thereby removing said regions;
wherein the first transfer layer is configured to be selectively processed relative to the particle beam patternable layer; and
removing the transfer layer using a second removal process which selectively removes regions of the transfer layer, wherein a shape of the second removal is substantially determined by a shape created by the regions removed by an earlier exposure.
2. The method of claim 1 , wherein the first exposing step achieved through ion milling, sputtering the particle beam, chemically assisted etching by the particle beam, or reactive ion etching of the particle beam patterned layer.
3. The method of claim 2 , wherein said first transfer layer is between said particle beam patternable layer and said second transfer layer.
4. The method of claim 2 , wherein the first transfer layer is configured to be selectively processed relative to the second transfer layer using said first removal process.
5. The method of claim 2 , wherein the second transfer layer is about 1 to 1000 nm thick.
6. The method of claim 5 , wherein the second transfer layer is about 5 to 500 nm thick.
7. The method of claim 6 , wherein the second transfer layer is about 10 to 200 nm thick.
8. The method of claim 2 , wherein the second transfer layer comprises organic material.
9. The method of claim 2 , wherein the first transfer layer is thinner than the second transfer layer.
10. The method of claim 2 , wherein the first transfer layer is about 1 to 1000 nm thick.
11. The method of claim 10 , wherein the first transfer layer is about 5 to 500 nm thick.
12. The method of claim 11 , wherein the first transfer layer is about 10 to 200 nm thick.
13. The method of claim 12 , wherein the first transfer layer is about 1 to 20 nm thick.
14. The method of claim 2 , wherein the first transfer layer comprises a metal.
15. The method of claim 14 , wherein the first transfer layer comprises titanium.
16. The method of claim 2 , wherein the first transfer layer comprises a semiconductor or metalloid.
17. The method of claim 16 , wherein the first transfer layer comprises silicon.
18. The method of claim 1 , wherein the particle beam patternable layer is about 0.1 angstrom to 200 nm thick.
19. The method of claim 18 , wherein the particle beam patternable layer is about 5 angstroms to 100 nm thick.
20. The method of claim 19 , wherein the particle beam patternable layer is about 20 angstroms to 10 nm thick.