A high-performance capacitorless 1T-DRAM based on Z-shaped electron-hole bilayer TFET and SiGe memory window

Abstract

In this paper, a novel capacitorless dynamic random access memory (Z-EHBTFET 1T-DRAM) is designed based on a Z-shaped electron-hole bilayer tunnel field-effect transistor and a SiGe memory window, and its storage performance is systematically analyzed and studied in detail through numerical simulation. A large number of electrons can be induced in the inverted L-shaped channel of Z-EHBTFET 1T-DRAM using gate 1 to create an electron-hole bilayer together with the source region, which increases the line tunneling electric field and ultimately improves the sensing margin (SM) and read current ratio (IR1/IR0). SiGe memory window helps to improve the storage capacity of holes, aiming to improve the retention time (RT) and SM. By optimizing the Ge-composition and width of the SiGe memory window, the thickness of the I-shaped channel, and the gate gap length, the SM of 2.03 μA/μm, IR1/IR0 of 3.58 × 104, and RT of 1.2 s can be obtained for Z-EHBTFET 1T-DRAM. Compared with most reported 1T1C-DRAMs and traditional 1T-DRAMs, it has better storage performance. Moreover, it can operate at a lower programming voltage while ensuring superior storage performance, making it has great application prospect in the low power consumption field.