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:
Aug. 12, 2025
Filed:
Sep. 12, 2022
Kioxia Corporation, Tokyo, JP;
Keita Kimura, Fujisawa Kanagawa, JP;
Kenri Nakai, Fujisawa Kanagawa, JP;
Kioxia Corporation, Tokyo, JP;
Abstract
According to one embodiment, a semiconductor memory device includes memory cells and a control circuit configured to control an erase operation on the memory cells. The control circuit sequentially executes, in the erase operation, a first erase process, a first erase verify process, a second erase process, and a second erase verify process on the memory cells, acquires, in the first erase verify process, first memory cells having a threshold voltage equal to or lower than a first verify voltage, from among the memory cells, acquires, in the second erase verify process, the number of second memory cells having a threshold voltage higher than the first verify voltage, from among the first memory cells, and determines whether the number of the second memory cells is larger than a first value or not.