Stencil design and method for cell projection particle beam lithography
View Patent ↗A method and system for particle beam lithography, such as electron beam (EB) lithography, is disclosed. The method and system include selecting one of a plurality of cell patterns from a stencil mask and partially exposing the cell pattern to a particle beam, such as an electron beam, so as to selectively project a portion of the cell pattern on a substrate.
1. A method for particle beam lithography comprising:
projecting a particle beam through a first aperture, thereby forming a defined-shape particle beam;
directing the defined-shape particle beam through a second aperture that defines a cell pattern indicative of an electronic circuit block; and
selectively projecting a portion of the cell pattern on a substrate by using the first aperture as a mask to limit the exposure area of the second aperture to thereby partially expose the cell pattern to the particle beam.
2. The method of claim 1 , wherein particle beam lithography comprises electron beam (EB) lithography, and wherein the particle beam comprises an electron beam.
3. The method of claim 1 , wherein particle beam lithography comprises optical (light) laser lithography, and wherein the particle beam comprises an optical (light) laser beam.
4. The method of claim 1 , wherein particle beam lithography comprises X-ray beam lithography, and wherein the particle beam comprises an X-ray beam.
5. The method of claim 1 , wherein the first aperture is formed in an exposure mask.
6. The method of claim 1 , wherein the first aperture comprises a rectangular aperture.
7. The method of claim 1 , wherein the second aperture is formed in a stencil mask.
8. The method of claim 1 , wherein the second aperture or cell pattern is one of a plurality of second apertures or cell patterns formed in the stencil mask.
9. The method of claim 1 , wherein the cell pattern in the stencil mask includes at least two independently usable block patterns adjoining each other in a single cell area.
10. The method of claim 9 , wherein the cell patterns comprise a rectangular, triangular, or rectilinear shape or contour.
11. The method of claim 9 , wherein open space is secured surrounding the adjoined block patterns, and wherein the open space includes a margin large enough to allow partial projection of one of the independent block patterns selectively.
12. The method of claim 9 , wherein the independently usable block patterns are arranged to adjoin each other either in a vertical direction or in a horizontal direction in the cell area.
13. The method of claim 9 , wherein the independently usable block patterns are arranged to adjoin each other in both vertical and horizontal directions.
14. The method of claim 1 , wherein the cell pattern in the stencil mask includes at least one block pattern and a plurality of repetitive patterns.
15. The method of claim 14 , wherein the plurality of repetitive patterns cyclically repeats.
16. The method of claim 14 , wherein the portion of the cell pattern projected on the substrate includes the at least one block pattern and at least one repetitive pattern.
17. The method of claim 14 , wherein open space is secured surrounding the adjoined block patterns and repetitive pattern in the stencil mask, and wherein the open space includes a margin large enough to allow partial projection of one block pattern and the designated portion of the repetitive pattern.
18. A system for particle beam lithography comprising:
a particle beam source;
a first mask positioned for exposure to the particle beam source, the first mask having a first aperture; and
a second mask positioned below the first mask and above a substrate, the second mask having a second aperture that defines a cell pattern indicative of an electronic circuit block,
wherein exposing the particle beam source to the first aperture to form a defined-shape particle beam and selectively exposing the defined-shape particle beam to the second aperture forms a partial image of the cell pattern on the substrate.
19. The system of claim 18 , wherein particle beam lithography comprises electron beam (EB) lithography, and wherein the particle beam source comprises an electron beam source.
20. The system of claim 18 , wherein particle beam lithography comprises optical (light) laser lithography, and wherein the particle beam source comprises an optical (light) laser beam source.
21. The system of claim 18 , wherein particle beam lithography comprises X-ray beam lithography, and wherein the particle beam source comprises an X-ray beam source.
22. The system of claim 18 , wherein the cell pattern in the stencil mask includes at least two independently usable block patterns adjoining each other in a single cell area.
23. The system of claim 22 , wherein the cell patterns comprise a rectangular, triangular, rectilinear, or polygonal shape or contour.
24. The system of claim 22 , wherein open space is secured surrounding adjoined block patterns, and wherein the open space includes a margin large enough to allow partial projection of at least one of the independent block patterns selectively.
25. The system of claim 22 , wherein those independently usable block patterns are arranged to adjoin each other either in a vertical direction or in a horizontal direction in the cell area.
26. The system of claim 22 , wherein the independently usable block patterns are arranged to adjoin each other in both vertical and horizontal directions.
27. The system of claim 18 , wherein the cell pattern in the stencil mask includes at least one block pattern and a plurality of repetitive patterns.
28. The system of claim 27 , wherein the plurality of repetitive patterns cyclically repeats.
29. The system of claim 27 , wherein the portion of the cell pattern projected on the substrate includes the at least one block pattern and at least one repetitive pattern.
30. The system of claim 27 , wherein open space is secured surrounding the adjoined block pattern and repetitive pattern in the stencil mask, and wherein the open space includes a margin large enough to allow partial projection of at least one block pattern and the designated portion of the repetitive pattern.
31. A stencil for particle beam lithography comprising:
a plurality of cell patterns, each cell pattern being indicative of an electronic circuit block, and each cell pattern having a plurality of exposure areas within a cell area that are individually selectable;
wherein the stencil is used as a second aperture mask in a particle beam writer, the particle beam writer comprising a particle beam source, a first aperture mask, and the second aperture mask, and
wherein exposing the particle beam source to the first aperture mask forms a defined-shape particle beam, and
wherein exposing a first exposure area of a first cell pattern to the defined-shape particle beam selectively projects a first image of at least a portion of the first cell pattern on a substrate, and
wherein exposing a second exposure area of the first cell pattern, that is different from the first exposure area, to the defined-shape particle beam selectively projects a second image of at least another portion of the first cell pattern, that is different than the first image, on the substrate.
32. The stencil of claim 31 , wherein particle beam lithography comprises electron beam (EB) lithography, and wherein the particle beam source comprises an electron beam source.
33. The stencil of claim 31 , wherein particle beam lithography comprises optical (light) laser lithography, and wherein the particle beam source comprises an optical (light) laser.
34. The stencil of claim 31 , wherein particle beam lithography comprises X-ray beam lithography, and wherein the particle beam source comprises an X-ray beam source.
35. The stencil of claim 31 , wherein each cell pattern includes at least two independently usable block patterns adjoining each other in the cell area.
36. The stencil of claim 35 , wherein each cell pattern comprises a rectangular, triangular, or rectilinear shape or contour so that each cell pattern is configured to mate to each other.
37. The stencil of claim 35 , wherein open space is secured surrounding the adjoined block patterns, and wherein the open space includes a margin large enough to allow partial projection of at least one of the independent block patterns selectively.
38. The stencil of claim 35 , wherein the independently usable block patterns are arranged to adjoin each other either in a vertical direction or in a horizontal direction in the cell area.
39. The stencil of claim 35 , wherein the independently usable block patterns are arranged to adjoin each other both in vertical and horizontal directions.
40. The stencil of claim 31 , wherein at least one cell pattern includes at least one block pattern and a plurality of repetitive patterns.
41. The stencil of claim 40 , wherein the plurality of repetitive patterns cyclically repeats.
42. The stencil of claim 40 , wherein the cell pattern projected on the substrate includes the at least one block pattern and at least one repetitive pattern.
43. The stencil of claim 40 , wherein open space is secured surrounding the adjoined block pattern and repetitive pattern, and wherein the open space includes a margin large enough to allow partial projection of one block pattern and the designated portion of the repetitive pattern.