Design of Multilevel Storage Medium through Sb₂Te₃/Ga₂Sb₃ Phase-Change Heterostructure

Abstract

Phase-change heterojunction Sb2Te3/Ga2Sb3 thin films with different thickness ratios and periods were designed and prepared by the magnetron sputtering technique. The multi-level resistance states of phase-change heterojunction Sb2Te3/Ga2Sb3 film were investigated from the perspective of material and device. As for the constant thickness ratio, both the phase transition temperature and electrical resistance increase with the decrease of periods. In particular, the heterojunction [Sb2Te3(7nm)/Ga2Sb3(3nm)]3 film experiences the twice resistance jumps at 208 and 290℃, respectively, exhibiting the obvious triple-resistance states. The phase structure and vibrational modes of [Sb2Te3(7nm)/Ga2Sb3(3nm)]3 film during the different crystallization stages were observed by the structural characterization.