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:
Feb. 11, 2014
Filed:
Feb. 19, 2013
Rouying Zhan, Gilbert, AZ (US);
Amaury Gendron, Scottsdale, AZ (US);
Chai Ean Gill, Chandler, AZ (US);
Rouying Zhan, Gilbert, AZ (US);
Amaury Gendron, Scottsdale, AZ (US);
Chai Ean Gill, Chandler, AZ (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
Methods for forming an electrostatic discharge protection (ESD) clamps are provided. In one embodiment, the method includes forming at least one transistor having a first well region of a first conductivity type extending into a substrate. At least one transistor is formed having another well region of a second opposite conductivity type, which extends into the substrate to partially form a collector. The lateral edges of the transistor well regions are separated by a distance D, which at least partially determines a threshold voltage Vtof the ESD clamp. A base contact of the first conductivity type is formed in the first well region and separated from an emitter of the second conductivity type by a lateral distance Lbe. The first doping density and the lateral distance Lbe are selected to provide a parasitic base-emitter resistance Rbe in the range of 1<Rbe<800 Ohms.