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. 22, 2014
Filed:
Apr. 18, 2006
Irfan Rahim, San Jose, CA (US);
Cheng-hsiung Huang, Cupertino, CA (US);
Irfan Rahim, San Jose, CA (US);
Cheng-Hsiung Huang, Cupertino, CA (US);
Altera Corporation, San Jose, CA (US);
Abstract
An electrostatic discharge (ESD) protection structure comprising a polysilicon gate on an insulating layer on a substrate, said gate having first and second sides, a first heavily doped P-region in the substrate on the first side of the gate, a first heavily doped N-region in the substrate on the second side of the gate, and a shallow trench isolation isolating said first P-region and said first N-region from other structures in the substrate. In a first embodiment, the heavily doped regions are formed in a well having opposite conductivity to that of the substrate and a diode is formed at a PN junction between one of the heavily doped regions and the well. To minimize capacitance between the well and the substrate, the substrate is doped at a level of native doping and the well is isolated so that no other wells or heavily-doped regions are nearby in the substrate. Doping levels in the well and the dimensions of the gate are controlled to minimize on resistance (R) of the diode. In a second embodiment, no well is used.