Martensitic phase transition and subsequent surface corrugation in manganese stabilized zirconia thin films

摘要

A martensitic phase-transition in pulsed-laser deposited manganese stabilized zirconia (MnSZ) thin films is demonstrated. For atomic Mn contents of Mn Zr O thin films between 0.1 and 0.15, the martensitic transformation of the tetragonal high temperature phase to the monoclinic low temperature phase is revealed. (001)-oriented MnSZ thin films exhibit a modification of surface morphology in the form of ordered pyramids. The surface morphology of (111)-oriented MnSZ thin films shows dislocation lines with a sixfold symmetry. Transmission electron microscopy demonstrates the change of the crystallographic phase within the MnSZ thin films. X-ray diffraction measurements reveal the presence of both the monoclinic as well as the tetragonal phases. By heating the MnSZ thin films in an oxygen-deficient atmosphere, i.e vacuum, the martensitic phase transition can be reversed. By growing MnSZ thin films at elevated temperatures, the tetragonal phase is stabilized. During cooling down from the growth temperature, MnSZ thin films change their colour slightly and defoliate partially from the substrate if the thickness is larger than about 600 nm and the Mn content within.