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. 02, 1999
Filed:
Mar. 18, 1997
Lorenzo Fratin, Milan, IT;
Carlo Riva, Renate, IT;
SGS-Thomson Microelectronics S.r.l., Agrate Brianza, IT;
Abstract
A MOS transistor capable of withstanding relatively high voltages is of a type integrated on a region included in a substrate of semiconductor material, having conductivity of a first type and comprising a channel region intermediate between a first active region of source and a second active region of drain. Both these source and drain regions have conductivity of a second type and extend from a first surface of the substrate. The transistor also has a gate which includes at least a first polysilicon layer overlying the first surface of at least the channel region, to which it is coupled capacitively through a gate oxide layer. According to the invention, the first polysilicon layer includes a mid-portion which only overlies the channel region and has a first total conductivity of the first type, and a peripheral portion with a second total conductivity differentiated from the first total conductivity. The peripheral portion partly overlies the source and drain active regions toward the channel region.