Graphite Carbon-Doped Sb2Te Nanostructures for Phase-Change Memory Applications

High thermal stability, fast operation speed, low thicknessvariation,and low resistance drift of phase-change nanomaterials are the essentialcharacteristics in phase-change memory (PCM) applications. In thiswork, we put forward a graphite carbon-doped Sb2Te (C-Sb2Te) chalcogenide with semiconductor process compatibility.Our results prove that the proposed C-Sb2Te has excellentthermal stability and high operation speed. More importantly, thethickness change and resistance drift are only 0.89% and 0.0149, respectively.The C-Sb2Te-based memory device exhibits a high switchingspeed to the instrument test limit (5 ns) with a large resistanceratio, low operation voltage (2 V), and low power consumption (6.9pJ). The proposed C-Sb2Te nanostructure material exceedsboth conventional Ge2Sb2Te5 and transition-metal-dopedSb(2)Te materials in terms of its performance. Abinitio molecular dynamics simulations reveal that C-Cand C-Sb bonds as well as C-C chains are formed in C-Sb2Te, and C doping constrains phase transition in a small regionand refines grains of C-Sb2Te, thus resulting in the highperformance. Our study suggests that C-Sb2Te is a potentialcandidate for high-speed, high-thermal-stability, and high-reliabilityPCM applications.