Bypass Resistive RAM With Interface Switching-Based Resistive RAM and InGaZnO Bypass Transistor for V-NAND Applications

We report a bypass resistive random-access memory (B-RRAM), which combines interface switching-based RRAM and an IGZO transistor, providing high compatibility with a vertical NAND (V-NAND) structure for high-density memory. The analog switching properties of the WOx resistive switching (RS) layer for the memory and the low off-state leakage current of the IGZO transistor (Tr) were utilized for the selector device. By utilizing the bypass reading between the RS and Tr layer, B-RRAM exhibits the favorable memory characteristics with a low operation voltage (~ 2 V), outstanding multibit operation (> 3 bits), and robust endurance (<inline-formula> <tex-math notation="LaTeX">$\sim ~10^{{6}}{)}$ </tex-math></inline-formula>. Furthermore, the B-RRAM also demonstrated a high on/off (<inline-formula> <tex-math notation="LaTeX">$ > 10^{{6}}{)}$ </tex-math></inline-formula> ratio and reasonable retention characteristics owing to the synergistic effects of RS and Tr layers. These results suggest that the B-RRAM has promising potential as a replacement for V-NAND flash memory.