Microelectronic air-gap structures and methods of forming the same

• US 6,509,623 B2
• Filed: 09/28/2001
• Issued: 01/21/2003
• Est. Priority Date: 06/15/2000
• Status: Expired due to Term

• Current Assignee: Newport Fab, LLC (Tower Semiconductor Limited)
• Original Assignee: Newport Fab, LLC (Tower Semiconductor Limited)
• Inventors: Zhao, Bin
• Primary Examiner(s): Smith, Matthew
• Assistant Examiner(s): YEVSIKOV, VICTOR V
• Application Number:
  US09/967,115
• Publication Number:
  US 20020016058A1
• Time in Patent Office: 480 Days
• Field of Search: 257/522, 257/414, 257/758, 438/619, 438/780, 438/781, 438/623
• US Class Current: 257/522
• CPC Class Codes: H01L 21/31144 using masks
• CPC Class Codes: H01L 21/764 Air gaps H01L21/76264 takes precedence
• CPC Class Codes: H01L 21/7682 the dielectric comprising air gaps
• CPC Class Codes: H01L 23/5221 Crossover interconnections
• CPC Class Codes: H01L 23/5222 Capacitive arrangements or effects of, or between wiring layers other capacitive arrangements H01L23/642
• CPC Class Codes: H01L 23/5329 Insulating materials
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An improved microelectronic structure is disclosed. The improved structure includes an air-gap region formed by removing an insulating material through an aperture residing in a mask.

Claims

1. A microelectronic structure comprising:

a substrate;

a plurality of features formed on the substrate, the plurality of features having an air-gap region therebetween;

a mask formed above said plurality of features and overlaying a portion of said air-gap region, said mask having an aperture, said aperture being configured to allow said air-gap region to be formed; and

a seal formed over said mask.

2. The microelectronic structure of claim 1, wherein the plurality of features comprise conductive material.

3. The microelectronic structure of claim 1, wherein the mask comprises silicon oxide.

4. The microelectronic structure of claim 1, wherein the mask comprises silicon nitride.

5. The microelectronic structure of claim 1, wherein the seal comprises spin-on deposited dielectric material.

6. The microelectronic structure of claim 1, further comprising a dielectric material interposed between the features and said mask.

7. A microelectronic circuit including the microelectronic structure of claim 1.

8. A micro-mechanical structure including the microelectronic structure of claim 1.

9. A microelectronic structure including an air-gap region comprising:

a first feature formed on a substrate;

a second feature formed on the substrate, thereby forming a gap between the first feature and the second feature; and

a mask having at least one aperture, the mask formed above the first feature, the second feature and the gap, and the aperture positioned above the gap so that an insulating material residing in the gap is removed through the aperture to create the air-gap region.

10. The microelectronic structure of claim 9, further comprising a seal formed over the mask such that the aperture is sealed after the insulating material residing in the gap is removed.

11. The microelectronic structure of claim 10, wherein the seal comprises spin-on deposited dielectric material.

12. The microelectronic structure of claim 10, further comprising a second insulating material formed over the seal.

13. The microelectronic structure of claim 9, wherein at least one of the first feature and the second feature comprises a conductive material.

14. The microelectronic structure of claim 9, wherein the removed insulating material comprises a dielectric material.

15. The microelectronic structure of claim 9, wherein the mask comprises silicon oxide.

16. The microelectronic structure of claim 9, wherein the mask comprises silicon nitride.

17. The microelectronic structure of claim 9, further comprising a dielectric material interposed between the features and the mask.

18. A microelectronic circuit including the microelectronic structure of claim 9.

19. A micro-mechanical structure including the microelectronic structure of claim 9.

20. A microelectronic structure, comprising:

a first element formed on a substrate;

a second element formed on the substrate, thereby defining a gap between the first element and the second element; and

a region of air residing in the gap, the region of air resulting from removing a portion of insulating material residing in the gap through an aperture on a mask, the mask covering the first element, the second element and the gap, and the aperture positioned over the gap.

21. The microelectronic structure of claim 20, further comprising a seal formed over the mask after the portion of the insulating material is removed.

22. The microelectronic structure of claim 21, further comprising a second insulating material formed over the seal.

23. The microelectronic structure of claim 20, wherein the removed portion of insulating material is removed by exposing the removed portion of insulating material to an oxygen plasma.

24. The microelectronic structure of claim 20, wherein the removed portion of insulating material is removed by exposing the removed portion of insulating material to a solvent.

25. The microelectronic structure of claim 20, wherein at least one of the first element and the second element is a conductor.