Claims
- 1. A method of forming an etch mask over a substrate, comprising the steps of:providing a substrate having a layer of mask material; disposing a plurality of micro-spheres over said mask layer; and patterning said mask layer using said micro-spheres.
- 2. A method according to claim 1, wherein said step of patterning comprises anisotropically plasma etching said mask layer to remove portions of said mask layer outside peripheries of respective said plurality of micro-spheres.
- 3. A method according to claim 2, wherein said step of anisotropically plasma etching comprises:selectively etching said mask layer more favorably relative said substrate, and using said substrate as an etch stop during said etching.
- 4. A method according to claim 2, wherein said substrate comprises silicon and said mask layer comprises oxide.
- 5. A method according to claim 4, wherein said mask layer of oxide is provided a thickness of less than 0.4 μm and said micro-spheres are provided a diameter in a range of 0.01 to 10 μm.
- 6. A method according to claim 4, wherein said micro-spheres comprise a polymer.
- 7. A method according to claim 5, wherein said micro-spheres comprise latex.
- 8. A method of etching a substrate, comprising the steps of:providing a substrate with a mask layer; disposing a plurality of beads having a diameter in a range of 0.01 to 10 μm over said mask layer; patterning said mask layer using said beads to define mask elements beneath respective said plurality of beads; and etching portions of said substrate while masked with said mask elements.
- 9. A method according to claim 8, further comprising a step of removing said mask elements and said plurality of beads after said step of etching the substrate.
- 10. A method according to claim 9, wherein said substrate comprises silicon and said mask layer comprises a thermal oxide formed with a thickness in a range of 0.05 to 0.1 μm.
- 11. A method of patterning a hard mask over a substrate, comprising the steps of:providing a layer of oxide over a substrate comprising silicon; providing a plurality of micro-spheres over said oxide layer; anisotropically plasma etching portions of said oxide layer to form mask elements of oxide corresponding to said micro-spheres and expose portions of said substrate outside peripheries of respective said plurality of micro-spheres.
- 12. A method according to claim 11, wherein said step of anisotropic plasma etching comprises:selectively etching oxide more favorably relative silicon, and using said substrate as an etch stop during said etching.
- 13. A method according to claim 12, wherein said micro-spheres are provided a diameter in a range of 0.01 to 10 μm and said oxide layer is provided a thickness of less than 0.4 μm.
- 14. A method according to claim 13, wherein said oxide layer is formed as a thermal oxide with a thickness in a range of 0.05 to 0.1 μm.
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is related to U.S. Pat. No. 5,302,239, issued on Apr. 12, 1994, entitled, “Method of making Atomically Sharp Tips useful in Scanning Probe Microscopes,” assigned to Micron Technology, Inc., and having a common inventor with the present application.
This is a divisional application of U.S. application Ser. No. 09/354,923, filed Jul. 15, 1999, now U.S. Pat. No. 6,126,845, which is a divisional application of U.S. application Ser. No. 09/024,877, filed on Feb. 17, 1998, which is a continuation application of U.S. application Ser. No. 08/665,620, filed on Jun. 18, 1996, now U.S. Pat. No. 5,753,130, which is a continuation of U.S. application Ser. No. 08/338,705, filed Nov. 14, 1994, abandoned, which is a continuation-in-part of U.S. application Ser. No. 08/184,819, filed on Jan. 21, 1994, now U.S. Pat. No. 5,391,259, which is a continuation-in-part of U.S. application Ser. No. 07/883,074, filed on May 15, 1992, now U.S. Pat. No. 5,302,238.
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Continuations (2)
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08/665620 |
Jun 1996 |
US |
Child |
09/024877 |
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Parent |
08/338705 |
Nov 1994 |
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08/665620 |
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Continuation in Parts (2)
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08/184819 |
Jan 1994 |
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08/338705 |
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07/883074 |
May 1992 |
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08/184819 |
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US |