Nonvolatile memory device

Abstract

A nonvolatile memory with a simple structure where recorded information can be read without destruction. A voltage is impressed between a control gate and a memory gate for writing. A ferroelectric layer is polarized in accordance with the direction of the impressed voltage. A control gate voltage to make channel is small when the ferroelectric layer is polarized with the control gate side being positive. Control gate voltage to make channel is large when the ferroelectric layer is polarized with the control gate side being negative. The reference voltage is impressed on the control gate for reading. A large drain current flows when the ferroelectric layer is polarized with a second polarization and a small drain current flows when the ferroelectric layer is polarized with a first polarization. Record information can be read by detecting the drain current. Polarization status of the ferroelectric is not destroyed in the reading operation.