Thermal stability of phase change GaSb\GeTe, SnSe\GeTe and GaSb\SnSe double stacked films revealed by X-ray reflectometry and X-ray diffraction

We report a study related to the influence of heat treatment (up to 300 °C) on the structure of GaSb\GeTe, SnSe\GeTe and GaSb\SnSe stacked phase change memory films and of their counterparts with Hf thin film barrier between the layers. Samples were prepared by pulsed laser deposition and investigated by X-ray reflectometry and X-ray diffraction in order to evaluate the inter-films diffusion and the temperature threshold where this process is initiated. The thickness and mass density variations of films after each heat treatment, as well as the efficiency of hafnium barrier film, to eliminate potential atomic diffusion issues, were investigated.