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. 16, 2004
Filed:
Aug. 13, 2002
Applicant:
Inventors:
Richard Francis, Manhattan Beach, CA (US);
Chiu Ng, El Segundo, CA (US);
Assignee:
International Rectifier Corporation, El Segundo, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/362 ;
U.S. Cl.
CPC ...
H01L 2/362 ;
Abstract
An IGBT is formed in a thin (less than 250 microns thick) float zone silicon wafer using a hydrogen implant to form an N buffer layer at the bottom of the wafer. A weak anode is formed on the bottom of the wafer. A single hydrogen implant, or a plurality of hydrogen implants of progressively shallower depth and increasing dose can be used to form the implant in a diffused float zone wafer. The process may also be used to form an N contact region in silicon to permit a good ohmic contact to the silicon for any type device.