Threshold Voltage Drift in Te-Based Ovonic Threshold Switch Devices Under Various Operation Conditions

Abstract

In this research, we investigate threshold voltage drift in a B-Te based OTS device under various operation conditions. To this aim, drift of threshold voltage after a switching process is examined. From the measurements, we find that the threshold voltage required to switch the device back after the first switching process decreases when the interval between the voltage pulsespplied for the switching is shorter than 10 mu s, and becomes drift-free afterward. This result implies that a certain amount of heat is generated during the first switch which results in higher local temperature that lowers the threshold voltage, and is dissipated completely after 10 mu s. A 3D finite element simulation is provided to demonstrate the thermal effect induced by the switching pulse. Our results demonstrate that the threshold voltage of the Te-based OTS device is affected by thermal effects during switching at short time scales, and thus indicate that the threshold voltage drift should be considered carefully in the fast device operation.