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:
Oct. 11, 2016
Filed:
Jan. 16, 2014
Xin Lin, Phoenix, AZ (US);
Daniel J. Blomberg, Chandler, AZ (US);
Hongning Yang, Chandler, AZ (US);
Jiang-kai Zuo, Chandler, AZ (US);
Xin Lin, Phoenix, AZ (US);
Daniel J. Blomberg, Chandler, AZ (US);
Hongning Yang, Chandler, AZ (US);
Jiang-Kai Zuo, Chandler, AZ (US);
FREESCALE SEMICONDUCTOR, INC., Austin, TX (US);
Abstract
Instability and drift sometimes observed in bipolar transistors, having a portion of the base extending to the transistor surface between the emitter and base contact, can be reduced or eliminated by providing a further doped region of the same conductivity type as the emitter at the transistor surface between the emitter and the base contact. The further region is desirably more heavily doped than the base region at the surface and less heavily doped than the adjacent emitter. In another embodiment, a still or yet further region of the same conductivity type as the emitter is provided either between the further region and the emitter or laterally within the emitter. The still or yet further region is desirably more heavily doped than the further region. Such further regions shield the near surface base region from trapped charge that may be present in dielectric layers or interfaces overlying the transistor surface.