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:
Nov. 27, 1990
Filed:
Feb. 01, 1988
Mishel Matloubian, Dallas, TX (US);
Cheng-Eng D Chen, Richardson, TX (US);
Terence G Blake, Dallas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
An MOS transistor is disclosed which has a guard ring for prevention of source-to-drain conduction through the isolation oxide after exposure to ionizing radiation. In the described example of an n-channel transistor, a p+ region is formed at the edges of the source region in a self-aligned fashion relative to the gate electrode so as not to extend under the gate to contact the drain region. This p+ region forms a diode which retards source-drain conduction even if a channel is formed under the isolating field oxide where the gate electrode overlaps onto the field oxide. The structure may be silicided for improved series resistance. An example of the transistor formed in an SOI configuration is also disclosed.