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. 19, 2011
Filed:
May. 15, 2007
Mingwei Xu, South Portland, ME (US);
Steven J. Adler, Cape Elizabeth, ME (US);
Mingwei Xu, South Portland, ME (US);
Steven J. Adler, Cape Elizabeth, ME (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A system and method are disclosed for providing a self aligned bipolar transistor using a silicon nitride ring. An active region of the transistor is formed and a sacrificial emitter is formed above the active region of the transistor. A silicon nitride ring is formed around the sacrificial emitter. The sacrificial emitter and the silicon nitride ring are formed by depositing a layer of silicon nitride material over the active area of the transistor and performing an etch process to simultaneously create both the sacrificial emitter and the silicon nitride ring. The silicon nitride ring provides support for forming a raised external base for the transistor.