Contact planarization using nanoporous silica materials

• US 20020168876A1
• Filed: 10/26/2001
• Published: 11/14/2002
• Est. Priority Date: 09/09/1999
• Status: Active Grant

• Current Assignee: Denis H. Endisch, James S. Drage
• Original Assignee: Denis H. Endisch, James S. Drage
• Inventors: Endisch, Denis H., Drage, James S.
• Granted Patent: US 6,797,607 B2
• Time in Patent Office: Days
• US Class Current: 438/787
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G03F 7/0002 Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping
• CPC Class Codes: H01L 21/31051 Planarisation of the insulating layers H01L21/31058 takes precedence

Abstract

A process for forming a substantially planarized nanoporous dielectric silica coating on a substrate suitable for preparing a semiconductor device, and semiconductor devices produced by the methods of the invention. The process includes the steps of applying a composition that includes at least one silicon-based dielectric precursor to a substrate, and then,

(a) gelling or aging the applied coating,

(b) contacting the coating with a planarization object with sufficient pressure to transfer a planar impression to the coating without substantially impairing formation of desired nanometer-scale pore structure,

(c) separating the planarized coating from the planarization object,

(d) curing said planarized coating;

wherein steps (a)-(d) are conducted in any one of the following sequences:

(a), (b), (c) and (d);

(a), (d), (b) and (c);

(b), (a), (d) and (c); and

(b), (c), (a) and (d).

Claims

1. A substantially planarized nanoporous dielectric silica coating on a substrate formed by a process comprising:

applying a composition that comprises a silicon-based precursor onto a substrate to form a coating on said substrate, and conducting the following steps;

(a) gelling or aging the applied coating,

(b) contacting the coating with a planarization object with sufficient pressure to transfer an impression of the object to the coating without substantially impairing formation of desired nanometer-scale pore structure,

(c) separating the planarized coating from the planarization object,

(d) curing said planarized coating;

wherein steps (a)-(d) are conducted in a sequence selected from the group consisting of

(a), (b), (c) and (d);

(a), (d), (b) and (c);

(b), (a), (d) and (c);

(b), (a), (c) and (d); and

(b), (c), (a) and (d).

2. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the silicon-based dielectric precursor is selected from the group consisting of an alkoxysilane, alkylalkoxysilane, a silsesquioxane, a hydrogensiloxane, a hydroorganosiloxane, a hydrogensilsesquioxane, an acetoxysilane, a halogenated silane and combinations thereof.

3. The substantially planarized nanoporous dielectric silica coating of claim 2 formed by process wherein the alkoxysilane comprises

4. The substantially planarized nanoporous dielectric silica coating of claim 3 formed by a process wherein each R is independently selected from the group consisting of methoxy, ethoxy, propoxy, and butoxy.

5. The substantially planarized nanoporous dielectric silica coating of claim 3 formed by a process wherein the alkoxysilane is selected from the group consisting of tetraethoxysilane, tetramethoxysilane and a combination thereof.

6. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the planarization object is an object having a contact surface selected from the group consisting of a flat surface, a curved surface and combinations thereof, wherein when said planarization object has said curved contact surface, said contacting step is conducted so that said curved contact surface is applied to said substrate with a rolling motion.

7. The substantially planarized nanoporous dielectric silica coating of claim 6 formed by a process wherein the planarization object is an optical flat having a contact surface comprising a layer selected from the group consisting of a non-stick release material, a gas-permeable non-stick release material, a non-stick release material with gas or vapor absorbing properties and combinations thereof.

8. The substantially planarized nanoporous dielectric silica coating of claim 7 formed by a process wherein the non-stick release material is separately removable from said planar object contact surface and the planarized coating.

9. The substantially planarized nanoporous dielectric silica coating of claim 6 formed by a process wherein the planarization object is contacted with the coating of step (a) with a force ranging from about 0.1 MPa to about 1 GPa.

10. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein said silicon-based precursor composition further comprises an aging promoter or catalyst selected from the group consisting of water, an acid, a base, a combination of water and an acid, and a combination of water and a base.

11. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein curing step (d) is conducted by heating the coating while in contact with the planarization object.

12. The substantially planarized nanoporous dielectric silica coating of claim 10 formed by a process wherein steps (a)-(d) are conducted in the sequence of (b), (a), (c) and (d).

13. The substantially planarized nanoporous dielectric silica coating of claim 11 formed by a process wherein the liquid base is a non-volatile amine selected from the group consisting of primary, secondary and tertiary alkylamines, aryl amines, alcohol amines and mixtures thereof which have a boiling point of about 200°

C. or less.

14. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the coating of step (a) is formed and applied onto the substrate by a combined stream process which comprises performing either (i) or (ii):

(i) (A) combining a stream of an alkoxysilane composition with a stream of a base containing catalyst composition to form a combined composition stream which is unbounded at a point of confluence; and

 

conducting steps (B) and (C) in either order or simultaneously;

(B) immediately depositing the combined composition stream onto a surface of the substrate;

(C) exposing the combined composition to water; and

(ii) (A) combining a stream of an alkoxysilane composition with a stream of water to form a combined composition stream which is unbounded at a point of confluence; and

(B) immediately depositing the combined composition stream onto a surface of the substrate.

15. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the coating of step (a) is applied onto the substrate by a method selected from the group consisting of spin-coating, dip coating, brushing, rolling, spraying, chemical vapor deposition and combinations thereof.

16. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the curing of step (d) is conducted by steps selected from the group consisting of heating, drying, evaporating and combinations thereof.

17. The substantially planarized nanoporous dielectric silica coating of claim 16 formed by a process wherein the heating step is conducted at a temperature ranging from about 350°

C. to about 600°

C. for a time period ranging from about 30 sec to about 5 minutes.

18. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the silicon-based precursor composition comprises at least one organic solvent.

19. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the coating is contacted with the planarization object under vacuum.

20. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process wherein the substrate comprises at least one semiconductor material.

21. The substantially planarized nanoporous dielectric silica coating of claim 1 formed by a process further comprising the step of treating the nanoporous dielectric silica coating with a surface modification agent under conditions sufficient to render the coating hydrophobic.

22. The substantially planarized nanoporous dielectric silica coating of claim 21 formed by a process wherein the surface modification agent comprises hexamethyldisilazane.

23. An integrated circuit that comprises at least one planarized nanoporous dielectric silica coating of claim 1.

25. The process of claim 24 wherein the process steps (a)-(d) are conducted in the order of (b), (a), (c) and (d).

27. The nanoporous dielectric silica coating of claim 26 formed by a process wherein said coating is aged or gelled while said patterned surface is in contact with said coating.

28. The nanoporous dielectric silica coating of claim 26 formed by a process wherein said coating is aged or gelled after said patterned surface is removed from contact with said coating.

29. The nanoporous dielectric silica coating of claim 26 formed by a process wherein said coating is aged or gelled before said patterned surface is contacted with said coating.

30. The nanoporous dielectric silica coating of claim 26 formed by a process wherein said patterned surface comprises at least one region that is at least 98 percent planar.

31. The nanoporous dielectric silica coating of claim 26 formed by a process wherein said patterned surface has multiple planar regions.

24. A process for forming a substantially planarized nanoporous dielectric silica coating on a substrate comprising:

applying a composition that comprises a silicon-based precursor onto a substrate to form a coating on said substrate, and conducting the following steps;

(a) gelling or aging the applied coating,

(b) contacting the coating with a planarization object with sufficient pressure to transfer an impression of the object to the coating without substantially impairing formation of desired nanometer-scale pore structure,

(c) separating the planarized coating from the planarization object,

(d) curing said planarized coating;

wherein steps (a)-(d) are conducted in a sequence selected from the group consisting of

(a), (b), (c) and (d);

(a), (d), (b) and (c);

(b), (a), (d) and (c);

(b), (a), (c) and (d); and

(b), (c), (a) and (d).

26. A dielectric silica coating on a substrate with a pattern impressed thereon by a process comprising:

coating a substrate with a composition comprising a precursor for forming a nanoporous dielectric film, contacting said coating with a desired patterned surface with a pressure and for a time period sufficient in impress the pattern on said coating, and then separating the patterned surface from said coating.

32. An integrated circuit that comprises at least one patterned dielectric silica coating of claim 26.