Ramon R Collazo

US Patent:

8148802, Apr 3, 2012

Filed:

Feb 16, 2011

Appl. No.:

13/028505

Inventors:

Ramon R. Collazo - Raleigh NC, US
Zlatko Sitar - Apex NC, US
Rafael Dalmau - Raleigh NC, US

Assignee:

North Carolina State University - Raleigh NC

International Classification:

H01L 23/58

US Classification:

257632, 257615, 257631

Abstract:

The present invention provides methods of protecting a surface of an aluminum nitride substrate. The substrate with the protected surface can be stored for a period of time and easily activated to be in a condition ready for thin film growth or other processing. In certain embodiments, the method of protecting the substrate surface comprises forming a passivating layer on at least a portion of the substrate surface by performing a wet etch, which can comprise the use of one or more organic compounds and one or more acids. The invention also provides aluminum nitride substrates having passivated surfaces.

US Patent:

20060257626, Nov 16, 2006

Filed:

May 11, 2006

Appl. No.:

11/382806

Inventors:

Raoul Schlesser - Cary NC, US
Ramon Collazo - Raleigh NC, US
Zlatko Sitar - Raleigh NC, US

International Classification:

B32B 18/00
B32B 9/00

US Classification:

428141000, 428698000, 428702000, 427248100, 427402000, 427331000

Abstract:

The present invention provides methods of preparing Group III-nitride films of controlled polarity and substrates coated with such controlled polarity films. In particular, the invention provides substrate preparation steps that optimize the substrate surface for facilitating growth of a Group III-polar film, an N-polar film, or a selectively patterned film with both a Group III-polar portion and an N-polar portion in precise positioning. The methods of the invention are particularly suited for use in CVD methods.

US Patent:

20100025823, Feb 4, 2010

Filed:

Jul 30, 2008

Appl. No.:

12/182475

Inventors:

Ramon R. Collazo - Raleigh NC, US
Zlatko Sitar - Apex NC, US
Rafael Dalmau - Raleigh NC, US

International Classification:

H01L 21/30
H01L 29/20

US Classification:

257615, 438694, 438795, 257E21213, 257E21211, 257E29089

Abstract:

The present invention provides methods of protecting a surface of an aluminum nitride substrate. The substrate with the protected surface can be stored for a period of time and easily activated to be in a condition ready for thin film growth or other processing. In certain embodiments, the method of protecting the substrate surface comprises forming a passivating layer on at least a portion of the substrate surface by performing a wet etch, which can comprise the use of one or more organic compounds and one or more acids. The invention also provides aluminum nitride substrates having passivated surfaces.

US Patent:

20120168772, Jul 5, 2012

Filed:

Mar 9, 2012

Appl. No.:

13/416182

Inventors:

Ramon R. Collazo - Raleigh NC, US
Zlatko Sitar - , US
Rafael Dalmau - Raleigh NC, US

International Classification:

H01L 29/20

US Classification:

257 76, 257E29089

Abstract:

The present invention provides methods of protecting a surface of an aluminum nitride substrate. The substrate with the protected surface can be stored for a period of time and easily activated to be in a condition ready for thin film growth or other processing. In certain embodiments, the method of protecting the substrate surface comprises forming a passivating layer on at least a portion of the substrate surface by performing a wet etch, which can comprise the use of one or more organic compounds and one or more acids. The invention also provides aluminum nitride substrates having passivated surfaces.

US Patent:

20220393431, Dec 8, 2022

Filed:

Jun 6, 2022

Appl. No.:

17/832769

Inventors:

- Adelphi MD, US
Alexander Franke - Raleigh NC, US
Zlatko Sitar - Apex NC, US
Ramon Collazo - Raleigh NC, US
Ronny Kirste - Durham NC, US
Dorian Alden - Raleigh NC, US

International Classification:

H01S 5/125
C30B 25/04
C30B 25/18
C30B 29/40
C30B 33/10

Abstract:

A method of making a Group III nitride material that includes: providing a substrate; patterning a template on the substrate; depositing a layer of a material comprising aluminum, gallium and nitrogen on the substrate at a temperature; annealing the layer comprising aluminum, gallium and nitrogen; epitaxially growing Distributed Bragg Reflectors to form a structure on the substrate that comprises microcavities; and etching micropillars in the structure for at least 30 seconds with a heated basic solution is described.