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:
Mar. 26, 2002
Filed:
Jun. 08, 2001
Katsuhiko Fukasaku, Tokyo, JP;
Atsuki Ono, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A process for preparing a semiconductor which is capable of implanting indium effectively during the process of forming a gate insulation film with different levels of thickness includes a 1 step of forming a 1 resist mask on a predetermined region lying on a P-type silicon substrate having an element isolation region formed thereon to form a P-well region before forming a 1 N-channel region made of components other than indium on the P-well region, a 2 step of removing the 1 resist mask before forming a 1 gate insulation film on the surface of the substrate, a 3 step of forming a 2 resist mask on the predetermined region except the 1 N-channel region after forming the 1 gate insulation film, and removing partially the 1 gate insulation film, a 4 step of forming a P-well region inside the 1 gate insulation film partially removed region before forming a 2 N-channel region containing indium on this P-well region, and a 5 step of removing the 2 resist mask before forming a 2 gate insulation film on the surface of the 2 N-channel region.