Evidence for electrically induced drift of threshold voltage in Ge_2Sb_2Te_5

摘要

Threshold voltage (V_T) is an important parameter in phase change memory (PCM), marking the minimum voltage needed to program the memory device. In this work, we demonstrate that subthreshold pulses at V ＜ V_T can induce an increase of V_T. The pulse-induced modification of V_T is explained primarily due to the Joule heating during V_T measurement accelerating the structural relaxation in the amorphous phase-change material. Our results demonstrate that V_T can be adjusted through applied voltage pulses in the subthreshold regime, allowing the stabilization of programmed PCM states.