Resistive switching characteristics of Al/Si₃N₄/p-Si MIS-based resistive switching memory devices

In this study, we proposed and demonstrated a self-rectifying property of a silicon nitride (Si₃N₄)-based resistive random access memory (RRAM) device by employing p-type silicon (p-Si) as the bottom electrode. The RRAM devices consisting of Al/Si₃N₄/p-Si are fabricated by using a low-pressure chemical-vapor deposition and exhibited an intrinsic diode property with non-linear current−voltage (I−V) behavior. In addition, compared to the conventional metal/insulator/metal (MIM) structure of Al/Si₃N₄/Ti RRAM cells, the operating current over the entire bias region for the proposed metal/insulator/semiconductor (MIS) cells is dramatically lower because the introduced p-Si bottom electrode efficiently suppresses the current in both the low- and the high resistance states. Then, the results mean that when p-Si is employed as a bottom electrode, the Si₃N₄-based RRAM cells can be applied to selector-free RRAM cells.