Methods of fabricating substrates

• US 9,653,315 B2
• Filed: 07/29/2014
• Issued: 05/16/2017
• Est. Priority Date: 12/04/2008
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Sills, Scott, Sandhu, Gurtej S., deVilliers, Anton
• Primary Examiner(s): Vinh, Lan
• Application Number:
  US14/445,478
• Publication Number:
  US 20140335694A1
• Time in Patent Office: 1,022 Days
• Field of Search: 438591, 438595, 438624, 438625, 438639, 438712, 438720, 438719, 438736, 438737, 216 41, 216 47, 216 49, 216 72, 430310, 430312
• CPC Class Codes: G03F 7/40 Treatment after imagewise removal, e.g. baking
• CPC Class Codes: H01L 21/0273 characterised by the treatment of photoresist layers
• 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 21/3086 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 21/3088 Process specially adapted to improve the resolution of the mask
• CPC Class Codes: H01L 21/31138 by dry-etching

Abstract

A method of fabricating a substrate includes forming spaced first features over a substrate. An alterable material is deposited over the spaced first features and the alterable material is altered with material from the spaced first features to form altered material on sidewalls of the spaced first features. A first material is deposited over the altered material, and is of some different composition from that of the altered material. The first material is etched to expose the altered material and spaced second features comprising the first material are formed on sidewalls of the altered material. Then, the altered material is etched from between the spaced second features and the spaced first features. The substrate is processed through a mask pattern comprising the spaced first features and the spaced second features. Other embodiments are disclosed.

Claims

1. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate, the spaced first features having elevationally coincident bases;

depositing an alterable material over the spaced first features and altering the alterable material with material from the spaced first features to form altered material on sidewalls of the spaced first features and having an elevationally innermost base that is elevationally coincident with the bases of the spaced first features;

depositing a first material over the altered material, the first material being of some different composition from that of the altered material;

etching completely through the first material and elevationally inward at least to the elevation of the elevationally coincident bases to expose the substrate between the spaced first features and to expose the altered material, said etching completely through the first material to expose the substrate also forming spaced second features that comprise the first material on sidewalls of the altered material; and

after forming the spaced second features, etching the altered material from between the spaced second features and the spaced first features.

2. The method of claim 1 wherein the spaced first features comprises photoresist.

3. The method of claim 1 wherein forming the spaced first features comprises forming spaced mask features followed by laterally trimming the spaced mask features to reduce their respective widths prior to depositing the alterable material.

4. The method of claim 1 wherein forming the spaced first features comprises forming spaced mask features followed by laterally trimming the spaced mask features to reduce their respective widths after the etching of the altered material.

5. The method of claim 1 wherein the first material is of some different composition from that of the spaced first features.

6. The method of claim 1 wherein the altering forms altered material over tops of the spaced first features.

7. The method of claim 1 wherein the alterable material has a planar outermost surface.

8. The method of claim 1 wherein the alterable material has a non-planar outermost surface.

9. The method of claim 1 wherein the altering occurs after completion of the deposition of the alterable material.

10. The method of claim 1 wherein no altering occurs until after completion of the deposition of the alterable material.

11. The method of claim 1 wherein the altering alters a portion of the alterable material adjacent each of the spaced first features to form the altered material while leaving portions of the alterable material distal the spaced first features unaltered.

12. The method of claim 1 wherein no etch mask other than the first material is received over any of the spaced first features during the etching of the first material.

13. The method of claim 12 wherein no etch mask is received anywhere over the substrate during the etching of the first material.

14. The method of claim 1 wherein no etch mask other than the altered material is received over any of the spaced first features during the etching of the altered material.

15. The method of claim 14 wherein no etch mask other than the altered material is received over the substrate during the etching of the altered material.

16. The method of claim 1 wherein the spaced first features comprise photoresist and the alterable material comprises one or more inorganic components dispersed in an organic composition that is cross-linkable upon exposure to acid, wherein the material from the spaced first features includes acid, and the altering the alterable material comprises forming cross-links within the organic composition upon exposure to the acid in the material from the spaced first features.

17. The method of claim 16 wherein the one or more inorganic components includes silicon.

18. The method of claim 16 wherein the one or more inorganic components includes metal.

19. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate;

depositing an alterable material over the spaced first features and altering the alterable material with material from the spaced first features to form altered material on sidewalls of the spaced first features;

depositing a first material over the altered material, the first material being of some different composition from that of the altered material and the same composition as that of the spaced first features;

etching completely through the first material and elevationally inward at least to the elevation of the elevationally coincident bases to expose the substrate between the spaced first features and to expose the altered material, said etching completely through the first material to expose the substrate also forming spaced second features that comprise the first material on sidewalls of the altered material; and

after forming the spaced second features, etching the altered material from between the spaced second features and the spaced first features.

20. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate;

depositing an alterable material over the spaced first features and altering the alterable material with material from the spaced first features to form altered material on sidewalls of the spaced first features, the altering occurring during deposition of the alterable material;

depositing a first material over the altered material, the first material being of some different composition from that of the altered material;

etching the first material to expose the altered material and forming spaced second features comprising the first material on sidewalls of the altered material; and

after forming the spaced second features, etching the altered material from between the spaced second features and the spaced first features.

21. The method of claim 20 wherein forming the spaced first features comprises forming spaced mask features followed by laterally trimming the spaced mask features to reduce their respective widths to greater than zero after the etching of the altered material.

22. The method of claim 20 wherein the first material is of the same composition as that of the spaced first features.

23. The method of claim 20 wherein the alterable material has a non-planar elevationally-outermost surface.

24. The method of claim 20 wherein after etching the altered material the second features are taller than the first features.

25. The method of claim 20 wherein respective laterally closest pairs of two immediately laterally adjacent of the second features have a respective void space laterally there-between.

26. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate;

depositing an alterable material over the spaced first features and altering the alterable material with material from the spaced first features to form altered material on sidewalls of the spaced first features, the altering alters a portion of the alterable material adjacent each of the spaced first features to form the altered material while leaving portions of the alterable material distal the spaced first features unaltered;

depositing a first material over the altered material, the first material being of some different composition from that of the altered material, etching the distal portions away selectively relative to the altered material prior to the depositing of the first material;

etching completely through the first material and elevationally inward at least to the elevation of the elevationally coincident bases to expose the substrate between the spaced first features and to expose the altered material, said etching completely through the first material to expose the substrate also forming spaced second features that comprise the first material on sidewalls of the altered material; and

after forming the spaced second features, etching the altered material from between the spaced second features and the spaced first features.

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

forming spaced first features over a substrate;

depositing an alterable material over the spaced first features and altering the alterable material with material from the spaced first features to form altered material on sidewalls of the spaced first features;

depositing a first material over the altered material, the first material being of some different composition from that of the altered material;

etching the first material to expose the altered material and forming spaced second features comprising the first material on sidewalls of the altered material; and

after forming the spaced second features, etching the altered material from between the spaced second features and the spaced first features, a resultant pattern after etching the altered material having pitch of about one third that of the spaced first features.

28. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate;

forming anisotropically etched spacers on sidewalls of the spaced first features;

depositing an alterable material over the anisotropically etched spacers and altering the alterable material with material from the anisotropically etched spacers to form altered material on a sidewall of each of the anisotropically etched spacers; and

after the altering, removing the anisotropically etched spacers from the substrate and forming spaced third features comprising the altered material.

29. The method of claim 28 comprising laterally trimming the spaced first features prior to said processing.

30. The method of claim 29 wherein the spaced first features are laterally trimmed prior to forming the anisotropically etched spacers.

31. The method of claim 29 wherein the spaced first features are laterally trimmed after removing the anisotropically etched spacers from the substrate.

32. The method of claim 29 wherein the spaced first features are laterally trimmed both prior to forming the anisotropically etched spacers and after removing the anisotropically etched spacers from the substrate.

33. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate;

depositing a first alterable material over the spaced first features and altering the first alterable material with material from the spaced first features to form first altered material on sidewalls of the spaced first features;

forming spaced second features comprising the first altered material and the spaced first features;

depositing a second alterable material over the spaced second features and altering the second alterable material with the first altered material from the spaced second features to form second altered material on sidewalls of the spaced second features;

forming spaced third features comprising the second altered material; and

etching the first altered material from between the spaced first features and the spaced third features.

34. The method of claim 33 wherein the spaced third features are taller than the spaced first features.

35. The method of claim 33 wherein the spaced first features comprises photoresist.

36. The method of claim 35 wherein forming the spaced first features comprises forming spaced mask features followed by laterally trimming the spaced masking features to reduce their respective widths prior to depositing the first alterable material.

37. The method of claim 35 wherein forming the spaced first features comprises forming spaced mask features followed by laterally trimming the spaced masking features to reduce their respective widths after the etching of the first altered material.

38. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate;

depositing a first material over the spaced first features which is of some different composition from that of the spaced first features, the first material being deposited to a thickness which is less than that of the spaced first features;

depositing a second material over the first material, the second material being of some different composition from that of the first material;

etching the second material to expose the first material and forming two spaced second features between adjacent spaced first features, the second features being spaced from the first features at least by first material received therebetween, the spaced second features comprising the first material elevationally under an elevationally innermost base of the second material;

etching the first material from between the spaced first features and the spaced second features; and

after the etching of the first material, laterally trimming width of the first features.

39. The method of claim 38 wherein the first material is deposited to a thickness which is less than that of the spaced first features.

40. The method of claim 38 wherein the second features are of substantially uniform maximum width, the laterally trimming producing a substantially uniform maximum first feature width that is substantially equal to the substantially uniform maximum width of the second features.

41. A method of fabricating a substrate, comprising:

forming spaced first features over a substrate, the forming of the spaced first features comprising forming spaced mask features followed by laterally trimming the spaced mask features to reduce their respective widths prior to depositing the alterable material;

depositing an alterable material over the spaced first features and altering the alterable material with material from the spaced first features to form altered material on sidewalls of the spaced first features, the altering occurring during deposition of the alterable material;

depositing a first material over the altered material, the first material being of some different composition from that of the altered material;

etching the first material to expose the altered material and forming spaced second features comprising the first material on sidewalls of the altered material; and

after forming the spaced second features, etching the altered material from between the spaced second features and the spaced first features.