The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 18, 2008
Filed:
Mar. 30, 2005
Werner K. Goetz, Palo Alto, CA (US);
Michael D. Camras, Sunnyvale, CA (US);
Xiaoping Chen, Legal Representative, San Jose, CA (US);
Gina L. Christenson, Sunnyvale, CA (US);
R. Scott Kern, San Jose, CA (US);
Chihping Kuo, Milpitas, CA (US);
Paul Scott Martin, Pleasanton, CA (US);
Daniel A. Steigerwald, Cupertino, CA (US);
Werner K. Goetz, Palo Alto, CA (US);
Michael D. Camras, Sunnyvale, CA (US);
Xiaoping Chen, legal representative, San Jose, CA (US);
Gina L. Christenson, Sunnyvale, CA (US);
R. Scott Kern, San Jose, CA (US);
Chihping Kuo, Milpitas, CA (US);
Paul Scott Martin, Pleasanton, CA (US);
Daniel A. Steigerwald, Cupertino, CA (US);
Philips Lumileds Lighting Company LLC, San Jose, CA (US);
Abstract
P-type layers of a GaN based light-emitting device are optimized for formation of Ohmic contact with metal. In a first embodiment, a p-type GaN transition layer with a resistivity greater than or equal to about 7 Ω cm is formed between a p-type conductivity layer and a metal contact. In a second embodiment, the p-type transition layer is any III-V semiconductor. In a third embodiment, the p-type transition layer is a superlattice. In a fourth embodiment, a single p-type layer of varying composition and varying concentration of dopant is formed.