Semiconductor memory device

Abstract From the Canadian patent

Abstract, A new type of nonvolatile static read/write memory cell is constructed with one MOS transistor and one MNOS transistor. These transistors together with a load resistor are complementarily combined to offer binary states in the lambda-shaped I-V curve for memory operation under normal power supply. Upon power failure, the MNOS transistor acts as a back-up element for nonvolatility. By impressing a control pulse on the drain of the MNOS transistor it is changed from the depletion mode to the enhancement mode thereby storing the last memory contents before the power failure. The stored nonvolatile memory contents can be easily retrieved. Thus a small size static random memory is …