A semiconductor memory system fabricated on one substrate is presented including an SRAM device, a DRAM device and a Flash memory device. In one embodiment the SRAM device is a high-resistive load SRAM device. In another embodiment the DRAM device is a deep trench DRAM device. A method is also presented for fabricating the memory system on one substrate having the SRAM device, the DRAM device and the Flash memory device.