This work presents a TCAD investigation of the operation of a Z2FET device for memory application, where the TCAD model is well calibrated to experimental hysteresis curves. The DC operation of the Z2FET has been analyzed for 4 cases, based on the permutations of the front and back gate biases, to identify and compare different modes of operation. The memory mode of operation is under the "Thyristor" like scenario with positive and negative biases applied to the front and back gates respectively. The dynamic property of Z2FET as a memory device is shown and its operation mechanism is described.