摘要
Chalcogenide phase-change materials(PCMs),in particular,the flagship Ge2Sb2Te5(GST),are leading candidates for advanced memory applications.Yet,GST in conventional devices suffer from high power consumption,because the RESET operation requires melting of the crystalline GST phase.Recently,we have developed a conductive-bridge scheme for low-power phase-change application utilizing a self-decomposed Ge-Sb-O(GSO)alloy.In this work,we present thorough structural and electrical characterizations of GSO thin films by tailoring the concentration of oxygen in the phase-separating GSO system.We elucidate a two-step process in the as-deposited amorphous film upon the introduction of oxygen:with increasing oxygen doping level,germanium oxides form first,followed by antimony oxides.To enable the conductive-bridge switching mode for femtojoule-level RESET energy,the oxygen content should be sufficiently low to keep the antimony-rich domains easily crystallized under external electrical stimulus.Our work serves as a useful example to exploit alloy decomposition that develops heterogeneous PCMs,minimizing the active switching volume for low-power electronics.
基金
The authors thank Miss Dan He and Miss Chenyu Liang at Instrument Analysis Center of Xi’an Jiaotong University for their assistance with Raman and XPS measurements.E M acknowledges the National Natural Science Foundation of China(Grant No.52150710545)
The authors acknowledge the 111 project 2.0(BP2018008)
the International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies of XJTU.W Z and E M also acknowledge the support of XJTU for their work at CAID.X M acknowledges the National Natural Science Foundation of China(Grant No.62174060)and the funding for Hubei Key Laboratory of Advanced Memories.
