Controllable On-Resistance and its Thermal-Induced Channel Expansive Model in Ovonic Threshold Switch Selector

Ovonic threshold switch (OTS) selector is a key enabler for developing high-density nonvolatile memory with crossbar arrays. In this work, we investigated the resistance characteristics of the OTS device at the ON state, which is pivotal in the integration of the OTS and the memory element. The results indicate that the ON-resistance is not a constant value in the OTS device and is uncorrelated with the device areas but dependent on the real-time power applied on the device that is at ON state. Then, we proposed a thermal-induced compact model to describe the ON-resistance in the OTS device, referring to the simulation of the expansive conductive channel in OTS. The proposed model matches well with the measured ON-resistances with different conditions in the study. Our results contribute to further understanding of the threshold switching mechanism and selecting appropriate operation conditions for the OTS selector integrated in the high-density memory array.