Bipolar resistive switching characteristics in Si3N4-based RRAM with MIS (Metal-Insulator-Silicon) structure

In this paper, bipolar resistive switching was investigated in our fabricated Ti/Si₃N₄/p⁺-Si resistive random access memory (RRAM) devices. Heavily doped p-type Si was used instead of a conventional bottom electrode (BE) using metal such as Pt. We found that forming-free process, self-compliance and gradual reset were shown in this device. The operation voltage was with 1.8~3.5 V during set process due to forming-free process. And self-compliance was observed by restriction of parasitic resistance without external current limiter. Finally, multi-level cell (MLC) feasibility was achieved using voltage stop during gradual reset.