Coexistence of analog and digital resistive switching behaviors in TiN/SiNx resistive random access memory device

Abstract

The digital–analog hybrid resistive random access memory can not only be used in computing in memory integrated circuits but also adapt to various requirements, such as achieving lower integration complexity. In this work, resistive memory devices with Ta/SiNx/TiN/Pt structures were fabricated, which exhibit a gradual analog or abrupt digital resistive state (DRS) characteristic depending on the different applied voltage range. The experimental results indicate that different RS switching of these devices is due to the change in the conductive mechanism in the SiNx/TiN double-layer structure. The Schottky barrier at the SiNx/TiN interface is the cause of analog resistive state characteristics under low sweeping voltage, while the formation/rupture of the conductive filaments formed under large voltage is the reason for the device to exhibit DRS characteristics.