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:
Sep. 30, 2014
Filed:
Aug. 06, 2009
Scott Gerard Balster, Dallas, TX (US);
Hiroshi Yasuda, Plano, TX (US);
Philipp Steinmann, Richardson, TX (US);
Badih El-kareh, Cedar Park, TX (US);
Scott Gerard Balster, Dallas, TX (US);
Hiroshi Yasuda, Plano, TX (US);
Philipp Steinmann, Richardson, TX (US);
Badih El-Kareh, Cedar Park, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
High voltage bipolar transistors built with a BiCMOS process sequence exhibit reduced gain at high current densities due to the Kirk effect. Threshold current density for the onset of the Kirk effect is reduced by the lower doping density required for high voltage operation. The widened base region at high collector current densities due to the Kirk effect extends laterally into a region with a high density of recombination sites, resulting in an increase in base current and drop in the gain. The instant invention provides a bipolar transistor in an IC with an extended unsilicided base extrinsic region in a configuration that does not significantly increase a base-emitter capacitance. Lateral extension of the base extrinsic region may be accomplished using a silicide block layer, or an extended region of the emitter-base dielectric layer. A method of fabricating an IC with the inventive bipolar transistor is also disclosed.