Correlation Between Microscopic and Macroscopic Properties of Yttria-Stabilized Zirconia Thin Films

The investigated films were deposited by e-beam evaporation of yttria-stabilized zirconia (YSZ) crystalline samples with the well-defined phase composition, on the n-doped Si (111) substrate at 750°C. The XRD of films exhibited their polycrystalline structure with a mixture of different phases, mainly the cubic phase. The electrical conductivity and the activation energy as the functions of yttria content indicated the present influence of isolated oxygen ion vacancies as well as the associated point defects. The relative effective permittivities (ɛ_r = 17-26) confirmed YSZ as a high-k gate dielectric also in the form of thin film. The measured microhardness data, evaluated with reference to the used substrate by Jonsson-Hogmark composite hardness model, (H = 5.9 - 10.8 GPa), and the high refractive index (n = 2.20 - 1.96) indicated YSZ to be a promising material for the protective coatings.