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:
Nov. 20, 1997
Applicant:
Inventor:
Toshiyuki Hayakawa, Yokohama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
438258 ; 438257 ; 438262 ; 438264 ; 438265 ; 257316 ; 257317 ;
Abstract
In a method of manufacturing a nonvolatile semiconductor memory device, a first polysilicon conductive layer, which is formed in a peripheral circuit region on a semiconductor substrate with a third gate insulating film interposed therebetween, is patterned into the shape of a gate electrode. A gate bird's beak is formed below the gate electrode in the peripheral circuit region by means of a heat treatment in an oxidizing atmosphere. Subsequently, in a memory cell array region, the first polysilicon conductive layer and a second polysilicon conductive layer laminated thereabove are processed to obtain a stacked gate structure.