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. 01, 2003
Filed:
Dec. 07, 1999
Delfo Nunziato Sanfilippo, Cantania, IT;
STMicroelectronics, S.R.L., Agrate Brianza, IT;
Abstract
Process of manufacturing a semiconductor device comprising a step of forming recessed zones in a semiconductor layer of a first conductivity type, a step of oxidation for forming a gate oxide layer at the sidewalls of the recessed zones, a step of forming a polysilicon gate electrode inside the recessed zones, a step of forming body regions of a second conductivity type in the semiconductor layer between the recessed zones, and a step of forming source regions of the first conductivity type in the body regions. The step of forming recessed zones comprises a step of local oxidation of the surface of the semiconductor layer wherein the recessed zones will be formed, with an oxide growth at the semiconductor layer's cost in order to obtain thick oxide regions penetrating in the semiconductor layer, and a step of etching wherein the oxide of the thick oxide regions is removed.