Ferroelectric memory using leakage current and multi-numeration system ferroelectric memory

摘要

A non-volatile ferroelectric memory using a leakage current of a dielectric and a multi-numeration system ferroelectric memory are provided. Unit cells are formed of a transistor. A dielectric or a ferroelectric is used as a gate insulating material. A ferroelectric capacitor is deposited on the upper portion of the gate insulating material and the upper electrode of a ferroelectric capacitor is used as a gate. "Writing" is performed by selecting a material in which the leakage current of the ferroelectric has a negligible value and the leakage current of the dielectric (used as the gate insulating material) is sharply increased. Charges induced between the drain and the source, are increased by applying the voltages which have various levels and identical pulse widths (in the case of "deleting" voltages, having identical levels and various pulse widths) making the leakage current of a various current densities flow through the gate insulating material. Thus, the multi-numeration system information can be stored.