Methods of forming a pattern on a substrate

• US 8,846,517 B2
• Filed: 12/19/2013
• Issued: 09/30/2014
• Est. Priority Date: 07/06/2012
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Sipani, Vishal, deVilliers, Anton J.
• Primary Examiner(s): Picardat, Kevin M
• Application Number:
  US14/133,962
• Publication Number:
  US 20140127909A1
• Time in Patent Office: 285 Days
• Field of Search: 438/595, 438/587, 438/588, 438/618, 438/622, 438/767, 438/778, 438/761
• US Class Current: 438/595
• CPC Class Codes: H01L 21/0337 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/0338 Process specially adapted to improve the resolution of the mask
• CPC Class Codes: H01L 21/31144 using masks

Abstract

A method of forming a pattern on a substrate includes forming longitudinally elongated first lines and first sidewall spacers longitudinally along opposite sides of the first lines elevationally over an underlying substrate. Longitudinally elongated second lines and second sidewall spacers are formed longitudinally along opposite sides of the second lines. The second lines and the second sidewall spacers cross elevationally over the first lines and the first sidewall spacers. The second sidewall spacers are removed from crossing over the first lines. The first and second lines are removed in forming a pattern comprising portions of the first and second sidewall spacers over the underlying substrate. Other methods are disclosed.

Claims

1. A method of forming a pattern on a substrate sequentially comprising:

forming longitudinally elongated first lines elevationally over an underlying substrate;

forming longitudinally elongated second lines elevationally over and crossing the first lines;

forming a masking material in spaces between sides of the crossing first and second lines to less than fill void space between immediately adjacent second lines; and

removing the first and second lines in forming a pattern comprising spaced regions of the masking material over the underlying substrate.

2. A method of forming a pattern on a substrate, comprising:

forming longitudinally elongated first lines and first sidewall spacers longitudinally along opposite sides of the first lines elevationally over an underlying substrate;

forming longitudinally elongated second lines and second sidewall spacers longitudinally along opposite sides of the second lines, the second lines and the second sidewall spacers crossing elevationally over the first lines and the first sidewall spacers, the first and second sidewall spacers being together formed during a single anisotropic etch of masking material;

removing the second sidewall spacers from crossing over the first lines; and

removing the first and second lines in forming a pattern comprising portions of the first and second sidewall spacers over the underlying substrate.

3. The method of claim 2 wherein the second sidewall spacers extend completely between immediately adjacent first lines after the removing of the second sidewall spacers from crossing over the first lines.

4. The method of claim 2 wherein the second lines are elevationally thicker between the first lines than atop the first lines.

5. A method of forming a pattern on a substrate, comprising:

forming longitudinally elongated first lines and first sidewall spacers longitudinally along opposite sides of the first lines elevationally over an underlying substrate;

forming longitudinally elongated second lines and second sidewall spacers longitudinally along opposite sides of the second lines, the second lines and the second sidewall spacers crossing elevationally over the first lines and the first sidewall spacers, the second sidewall spacers having elevationally outermost surfaces that are elevationally inward of elevationally outermost surfaces of the second lines;

removing the second sidewall spacers from crossing over the first lines; and

removing the first and second lines in forming a pattern comprising portions of the first and second sidewall spacers over the underlying substrate.

6. The method of claim 5 comprising forming the first sidewall spacers as a ring around the respective first lines.

7. The method of claim 5 comprising forming the second sidewall spacers as a ring around the respective second lines.

8. The method of claim 5 wherein the first and second sidewall spacers are together formed during a single anisotropic etch of masking material.

9. The method of claim 5 wherein forming the second sidewall spacers comprises depositing and subsequently anisotropically etching a masking material.

10. The method of claim 9 wherein the removing of the second sidewall spacers from crossing over the first lines comprises continuing the anisotropically etching of the masking material without stopping the etching between the forming of the second sidewall spacers and the removing of the second sidewall spacers from crossing over the first lines.

11. A method of forming a pattern on a substrate, comprising:

forming longitudinally elongated first lines and first sidewall spacers longitudinally along opposite sides of the first lines elevationally over an underlying substrate;

forming longitudinally elongated second lines and second sidewall spacers longitudinally along opposite sides of the second lines, the second lines and the second sidewall spacers crossing elevationally over the first lines and the first sidewall spacers, the first and second lines physically contacting one another where such cross;

removing the second sidewall spacers from crossing over the first lines; and

removing the first and second lines in forming a pattern comprising portions of the first and second sidewall spacers over the underlying substrate.

12. The method of claim 11 wherein the second sidewall spacers extend completely between immediately adjacent first lines after the removing of the second sidewall spacers from crossing over the first lines.

13. The method of claim 11 wherein the second lines are elevationally thicker between the first lines than atop the first lines.

14. A method of forming a pattern on a substrate, comprising:

forming longitudinally elongated first lines elevationally over an underlying substrate;

forming longitudinally elongated second lines and masking material longitudinally along opposite sides of the second lines and the first lines, the second lines and the masking material crossing elevationally over the first lines, the second lines and the masking material being elevationally thicker between the first lines than elevationally over the first lines;

removing the masking material from crossing over the first lines and from being along a majority of length of the first lines while leaving at least some of the masking material along sidewalls of the second lines between immediately adjacent first lines; and

removing the first and second lines in forming a pattern comprising spaced regions of the masking material over the underlying substrate.

15. The method of claim 14 comprising forming the first and second lines to have respective planar elevationally outermost surfaces.

16. A method of forming a pattern on a substrate, comprising:

forming longitudinally elongated first lines and first sidewall spacers longitudinally along opposite sides of the first lines elevationally over an underlying substrate;

forming longitudinally elongated second lines and second sidewall spacers longitudinally along opposite sides of the second lines, the second lines and the second sidewall spacers crossing elevationally over the first lines and the first sidewall spacers;

removing the second sidewall spacers from crossing over the first lines;

removing the first and second lines in forming a pattern comprising portions of the first and second sidewall spacers over the underlying substrate;

after removing the first and second lines, forming fill material laterally of the portions of the first and second sidewall spacers;

removing remaining of the portions of the first and second sidewall spacers in forming a mask comprising the fill material; and

using the mask while etching contact openings into the underlying substrate.

17. The method of claim 16 wherein the portions of the first and second spacers in the pattern are generally rectangular in horizontal cross-section having adjacent sides of unequal length.

18. The method of claim 17 wherein the rectangular portions have longer sides that are about three times length of the shorter sides.

19. The method of claim 17 wherein the rectangular portions have longer sides that are more than three times length of the shorter sides.