Nonvolatile semiconductor memory device

Abstract

A nonvolatile semiconductor memory device includes: a memory unit; and a control unit. The memory unit includes: first and second memory strings including first and second memory transistors with first and second select gates, respectively; and first and second wirings connected thereto. In a selective erase operation of a selected cell transistor of the first memory transistors, the control unit applies Vvoltage to the first wiring, applies Vvoltage lower than Vto a selected cell gate of the selected cell transistor, applies Vvoltage not higher than Vand higher than Vto a non-selected cell gate of the first memory transistors, applies Vor Vvoltage not higher than Vand not lower than Vto the first select gate, and applies Vor Vvoltage higher than Vand not higher than Vto the second wiring or sets the second wiring in a floating state.