Phase transformations in ultra-thin chalcogenide films: From in-situ calorimetric monitoring to advanced modeling of the confined process kinetics

The proposed project is aimed at detailed and extensive study of phase transformations (mainly the amorphous-to-crystalline conversion) in ultra-thin chalcogenide films under confinement within multilayer environment. First, the methodology for the differential scanning calorimetry (DSC) measurements will be developed and optimized (sensitivity-wise) for the major archetypal phase transformations and model chalcogenide films in as-deposited state (not scraped-off) on different substrates. Secondly, the DSC thermo-kinetic measurements and the supplemental characterization will be performed to analyze how the phase transformations in chalcogenide ultra-thin films are influenced by the film thickness, type of confinement, and internal stress. At this stage, the thin films will be already buffered by technologically relevant supportive layers, the thickness of which will control the internal stress and rigidity. The DSC data will be used to develop a new generation of solid-state kinetic models, accounting for variable activation energy and heterogeneous nucleation/growth domains.

Keywords:

chalcogenides; ultra-thin films; differential scanning calorimetry; crystal growth; phase transformations; solid-state kinetics