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:
Apr. 13, 1999
Filed:
Sep. 19, 1996
Applicant:
Inventors:
Esin Kutlu Demirlioglu, Cary, NC (US);
Monir H El-Diwany, Saratoga, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438307 ; 438529 ;
Abstract
A high voltage NMOS device includes an extended drain region formed by implantation of arsenic and phosphorus and a drivein of both the species. The dosage of arsenic is substantially higher than the dosage of phosphorus, so that upon drivein, the slower diffusing arsenic is highly concentrated near the surface of the extended drain region, while the more rapidly diffusing phosphorus provides a gradual gradient of concentration of dopant into the extended drain region.