Superlattice-like Sb50Se50/Ga30Sb70 thin films for high-speed and high density phase change memory application

Abstract

Multi-level phase change character of superlattice-like (SLL) Sb50Se50/Ga30Sb70 thin films was investigated through in-situ film resistance measurement. SLL structure of the thin films was confirmed by using transmission electron microscopy. Three resistance states were observed during heating process, and their thermal stability was also examined. A picosecond laser pump-probe system was used to measure phase-change time of the SLL Sb50Se50/Ga30Sb70 thin films. Phase change memory cells based on the SLL [SS(5 nm)/GS(10 nm)]3 thin films were fabricated to test and verify multi-level switch between set and reset states.