Appearance of high-temperature phase in zirconia films made by aerosol gas deposition method

Abstract

The aerosol gas deposition method (AGD) is a low-temperature method. No heating occurs during the AGD process when forming the AGD films. Nevertheless, ceramic films can be synthesized at room temperature directly from the source ceramic powders. In this paper, we report that the high-temperature phase of zirconia was found in zirconia films synthesized by AGD and that a light emission phenomenon was observed at the deposition site. The generation of the high-temperature phase was dependent on the mean diameter of the source ceramic powders. Both a small powder of less than two or three microns in diameter and large powder particles of more than 10 microns in diameter have the low possibility of generating the high-temperature phase when compared to that of 7-micron diameter powder. The appearance of the high-temperature phase and the light emission might be related to the formation mechanism of the AGD film at ambient temperature.