FET-TYPE FERROELECTRIC MEMORY CELL AND FET-TYPE FERROELECTRIC MEMORY

摘要

PROBLEM TO BE SOLVED: To provide an FET-type ferroelectric memory cell to and from which a plurality of bid data can be written and read, and an FET-type ferroelectric memory.;SOLUTION: The planar shape or the like of a semiconductor region 140a below an upper electrode 150 and a semiconductor region 140b below an upper electrode 160 out of a semiconductor layer 140 are changed to cause resistance values to be different between the semiconductor regions 140a and 140b. The resistance values of the semiconductor regions 140a, 140b also change according to the polarization direction of an adjacent ferroelectric layer 130. If the polarization direction of the ferroelectric layer 130 responsive to 0 or 1 is decided in advance and the polarization direction is controlled for each region below the upper electrodes 150, 160, then it is possible to write 2 bit data to one FET-type ferroelectric memory cell 100. Since the resistance value of the semiconductor layer 140 varies with the written data, it is possible to identify the written data from a current value which is detected when a reading voltage is applied between the upper electrodes 150, 160.;COPYRIGHT: (C)2006,JPO&NCIPI