Cycling Induced Metastable Degradation in GeSe Ovonic Threshold Switching Selector

Ovonic threshold switching (OTS) selector is a promising candidate to suppress the sneak current paths in emerging memory arrays, but there still gap between its performance and rigorous requirement from devices, especially endurance improvement hindered by insufficient understanding of mechanism. In this work, cycling induced degradation GeSe-based OTS selectors studied with electrical characterization techniques. The existence metastable state on- off-state during observed statistically analyzed alongside gradual leakage increase. Such may be attributed generation unstable Ge-Ge bonds that might element segregation, which also responsible for higher GeSe after large or Ge component. This work provides experimental guidance optimizing selectors.