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:
Jul. 29, 2003
Filed:
Nov. 20, 2000
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
To enhance the withstand voltage of an LD MOS transistor, a method of fabricating a semiconductor device according to the invention is characterized in that a process for forming a drift region is composed of a step for implanting phosphorus ions and arsenic ions different in a diffusion coefficient into the superficial layer of a substrate, a step for forming a selective oxide film (a first gate insulating film) 9A and an element isolation film 9B by selective oxidation and diffusing the phosphorus ions and the arsenic ions and a step for implanting and diffusing boron ions, and in that in the step for forming the selective oxide film 9A and the element isolation film 9B by selective oxidation in a state in which an oxide film and a polycrystalline silicon film are laminated on the substrate, only a drift region formation region is selectively oxidized in a state in which the polycrystalline silicon film is removed.