Mechanical properties of ferroelectric composite thin films

摘要

Ferro-electric (BSTO) films of 1 mu m nominal thickness were deposited on single crystals of sapphire at substrate temperatures varying from 30 deg C to 700 deg C. Optical analysis showed that the thin films were amorphous up to 500 deg C, while at 700 deg C they were polycrystalline. The microstructure of the thin films was columnar at all substrate temepratures. The film microhardness increased with increasing substrate temperature. While the cohesion failure load of the films remained fairly constant, the adhesion failure load increased with increasing substrate temperature.