Change in the resistivity of Ge-doped Sb phase change thin films grown by chemical vapor deposition according to their microstructures

Abstract

This study examined the effects of the composition and microstructure on the electric resistivity of Ge-doped Sb phase change thin films grown by cyclic plasma enhanced chemical vapor deposition. Ge and Sb layers were deposited sequentially to form either a GexSby mixture or Ge/Sb nanolaminated films. While the resistivity of the nanolaminated films was higher, the GexSby mixture showed a lower resistivity than the pure Sb film. This can be explained by the increase in carrier density of the alloy, as confirmed by first-principles calculations. An abrupt change in resistance accompanying a phase change was observed at ∼210 °C.