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:
Jul. 16, 1991
Filed:
Jan. 02, 1990
Applicant:
Inventors:
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
357 13 ; 357 52 ; 357 20 ; 357 58 ;
Abstract
A high voltage semiconductor structure having multiple guard rings, wherein guard rings farthest from a main junction are spaced further from each other than are guard rings closer to the main junction is provided. An enhancement region, which is of an opposite conductivity type from the guard rings, is formed between the guard rings to increase punch-through voltage between the guard rings, thereby increasing the breakdown voltage of the device. The enhancement region and close guard ring spacing result in a fine gradation of electric field and high punch-through breakdown voltage between guard rings.