TAOS based Cu/TiW/IGZO/Ga2O3/Pt bilayer CBRAM for low-power display technology

Abstract

We demonstrate the characteristics of a conductive-bridging random access memory (CBRAM) with Cu/TiW/InGaZnO/Ga2O3/Pt stack structure. The addition of a thin metal-oxide layer (4.5 nm-thick Ga2O3) in the bottom of the CBRAM device significantly increases the off-state resistance (Rom') and the memory window. The IGZO bi-layer CBRAM shows the excellent memory performances, such as low operation current (down to 50 A), high on/off resistance ratio (> 10(3)), high switching endurance (up to 10(3) cycles) and the capability of multi-level tuning. Meanwhile, high thermal stability was also achieved. Three decades of resistance window is constantly maintained beyond 10(4)s at 85 degrees C. The resistive switching stability and electrical uniformity of bi-layer IGZO/Ga2O3 CBRAM device are obviously enhanced as compared with the one only with a single layer of IGZO film. These results have given a great potential for the transparent amorphous oxide semiconductor (TAOS)-based material utilizing in CBRAM stacks and integrating into the display circuits for future memory-in-pixel applications.