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. 13, 2010
Filed:
Oct. 03, 2006
Lung-ching Kao, Taipei, TW;
Pu-ju Kung, Taipei, TW;
Lung-Ching Kao, Taipei, TW;
Pu-Ju Kung, Taipei, TW;
Vishay General Semiconductor LLC, Hauppauge, NY (US);
Abstract
A multiple layer overvoltage protection device is provided. The method begins by providing a substrate having a first impurity concentration of a first conductivity type to define a mid-region layer. A dopant of a second conductivity type is introduced into the substrate with a second impurity concentration less than the first impurity concentration. An upper base region having a second type of conductivity is formed on the upper surface of the mid-region layer. A lower base region layer having a second type of conductivity is formed on a lower surface of the mid-region layer. A first emitter region having a first type of conductivity is formed on a surface of the upper base region layer. A first metal contact is coupled to the upper base region layer and a second metal contact is coupled to the lower base region layer.