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:
Dec. 07, 2004
Filed:
May. 31, 2002
Edouard de Frésart, Tempe, AZ (US);
Patrice Parris, Phoenix, AZ (US);
Richard J De Souza, Tempe, AZ (US);
Jennifer H. Morrison, Chandler, AZ (US);
Moaniss Zitouni, Gilbert, AZ (US);
Xin Lin, Chandler, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A Bipolar Junction Transistor (BJT) that reduces the variation in the current gain through the use of a trench pullback structure. The trench pullback structure is comprised of a trench and an active region. The trench reduces recombination in the emitter-base region through increasing the distance charge carriers must travel between the emitter and the base. The trench also reduces recombination by reducing the amount of interfacial traps that the electrons injected from the emitter are exposed to. Further, the trench is pulled back from the emitter allowing an active region where electrons injected from a sidewall of the emitter can contribute to the overall injected emitter current. This structure offers the same current capability and current gain as a device without the trench between the emitter and the base while reducing the current gain variation.