A study of phase transition behaviors of chalcogenide layers using in situ alternative-current impedance spectroscopy

作者：Huang Yin Hsien; Huang Yu Jen; Hsieh Tsung Eong^*

来源：Journal of Applied Physics, 2012, 111(12): 123706.

DOI：10.1063/1.4729528

Electrical properties of chalcogenide thin films, both pristine Ge2Sb2Te5 (GST) and cerium-doped GST, were investigated by in situ alternative-current (AC) impedance spectroscopy. With the aid of brick-layer model and nano-grain composite model, the roles of grain and grain-boundary on the phase transition of chalcogenides were distinguished and the dominance of grain boundary was observed. Tangent loss behaviors deduced by impedance analysis revealed alien-element doping alters the interfacial polarization and delays the phase-transition rate of GST. Analytical results also illustrated that the in situ AC impedance spectroscopy can be an alternative tool for characterizing the phase-change kinetics of chalcogenides thin films with nano-scale grain sizes.

• 出版日期2012-6-15