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:
May. 08, 2001
Filed:
Dec. 22, 1999
William F. Richardson, San Antonio, TX (US);
Anhkim Duong, San Antonio, TX (US);
Other;
Abstract
A method is disclosed for reproducibly and controllably enhancing the current gain of a bipolar junction transistor. Prior to depositing an extrinsic emitter region of polycrystalline silicon, the surface of a monocrystalline silicon substrate is nitridized to grow a layer of silicon nitride thereon. The interfacial layer of silicon nitride functions as a tunnel insulator to enhance the current gain of the transistor and as a diffusion barrier to prevent thickening of the tunnel insulator due to the growth of a native oxide layer while exposed to an oxygen-containing atmosphere. The ubiquitous native silicon oxide on the surface of the monocrystalline silicon substrate may be optionally removed either before nitridation or after nitridation.