Effect of a thin Ti interfacial layer on the thermal resistance of Ge_2Sb_2Te_5-TiN stack

摘要

We study the dependence of the thermal resistance of TiN/Ge_2Sb_2Te_5 stacks on Si in the presence or not of a thin Ti interfacial layer. While for TiN/Ge_2Sb_2Te_5 almost ideal thermal properties of the interfaces are found, a different behaviour is measured for TiN/Ti/Ge_2Sb_2Te_5. After exposure to temperatures up to 440 ℃, the thermal resistance results to be lower than expected despite both the formation of the TiTe_2 phase, the depletion of Te inside Ge_2Sb_2Te_5, and the non complete development of the hexagonal structure. Those observations have been also validated on the SiO_2/Ge_2Sb_2Te_5 stack with and without Ti interfacial layer.