NONVOLATILE SEMICONDUCTOR MEMORY DEVICE

摘要

A nonvolatile semiconductor memory device of a floating-gate type comprises a floating-gate and two control gates. The floating-gate is divided into two conductive regions having a conductivity type opposite to each other. A first control gate is placed above a first region and a second control gate is placed above a second region. In this device, the erase operation is performed by causing avalanche breakdown within the floating-gate.