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. 24, 1987
Filed:
Jul. 15, 1985
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
357 235 ; 365168 ;
Abstract
A semiconductor memory device wherein a portion of source region of a field-effect transistor that serves as a memory cell has a low impurity concentration, so that hot carriers generated on the source side are injected into the floating gate. Hot carriers are generated by utilizing a large electric field intensity established by the drop of voltage in the region of low impurity concentration. The voltage difference is so great between the source region and the control gate that hot carriers generated on the source side are efficiently injected into the floating gate.