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. 03, 2009
Filed:
Jul. 13, 2006
San-jung Chang, Hsinchu, TW;
Jim Lin, Taoyuan County, TW;
San-Jung Chang, Hsinchu, TW;
Jim Lin, Taoyuan County, TW;
ProMOS Technologies, Inc., Hsinchu, TW;
Abstract
A method of fabricating a metal-oxide-semiconductor (MOS) transistor is provided. First, a patterned hard mask layer with an opening therein is formed over the substrate. A spacer is formed on the sidewall of the patterned hard mask layer in the opening. An isotropic etching process is performed on the substrate to form a recess in the substrate. An ion implant process is performed on the substrate in the lower portion of the recess using oxidation-restrained ions. The spacer is removed. Then, a thermal process is performed to form a gate oxide layer on the surface of the substrate within the recess such that the gate oxide layer in the upper portion of the recess is thicker than that in the lower portion of the recess.