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:
Feb. 15, 1994
Filed:
Feb. 28, 1992
Applicant:
Inventors:
Hisao Katto, Hinode, JP;
Jun Sugiura, Musashino, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 52 ; 437 26 ; 437 27 ; 437 28 ; 437 47 ; 437 48 ; 437 60 ;
Abstract
A heavily-doped semiconductor region and a channel stopper region, which are disposed under a memory cell in a memory cell region, are simultaneously formed after formation of a field insulator film, thereby preventing the channel stopper region from oozing out into the channel region, and thus obtaining a semiconductor memory device which is resistant to .alpha.-rays and therefore free from soft errors caused by .alpha.-rays. Also disclosed is a method of producing said semiconductor memory device.