WRITE-IN METHOD AND READ-OUT METHOD FOR FERROELECTRIC MEMORY DEVICE, AND FERROELECTRIC MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To increase the memory capacity, to reduce the chip area, and to reduce the manufacturing cost without increasing the number of memory cells.;SOLUTION: A write-in control circuit 107 is provided with a write-in voltage control circuit 106 generating and controlling a different inversion potential by which different optimized polarization is generated when applying voltage is stopped at the time of write-in, or the write-in control circuit 107 is provided with a write-in time control circuit for controlling a time required for applying voltage by which different optimized polarization is generated when applying voltage of an inversion potential is stopped. Thereby, as a multi-level value can be stored in one memory cell, memory capacity can be increased without changing the number of memory cells.;COPYRIGHT: (C)2002,JPO