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:
Dec. 06, 1977
Filed:
Apr. 15, 1976
Applicant:
Inventors:
Assignee:
Fujitsu Limited, , JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
357 24 ; 357 23 ; 357 45 ;
Abstract
A semiconductor memory device, which comprises: a P-type semiconductor material comprising on the surface thereof, an N-type doped layer, one surface region of the substrate adjoining the doped layer being used as a gate region, and further comprising in the interior thereof an N-type buried layer below another surface region of said substrate adjoining said one surface region. Electric charges representing information are stored in the buried layer. The reading time and the refreshing period are improved by shortening said reading time and lengthening said refreshing time utilization of said N-type buried layer.