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. 21, 1993
Filed:
Apr. 02, 1991
Jun Kudo, Nara, JP;
Tsutomu Ashida, Yamatokoriyama, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A nonvolatile semiconductor memory device comprises a memory cell array and a redundant circuit. The memory cell array comprises a plurality of cell lines for storing fixed data. The redundant circuit comprises redundancy memory cell rows of MOS transistors, and at least one redundancy spare decoder by which at least one of the redundancy memory cell rows is selectively determined and permuted with a memory cell to be repaired. At least one of the redundancy memory cell rows has data to be recovered stored therein. The data to be recovered is stored in the redundancy memory cell rows by selectively implanting channel regions of the memory cell rows with an impurity ion of high energy.