Mechanism of in-plane alignment in magnetron sputtered biaxially aligned yttria-stabilized zirconia

Biaxially aligned yttria-stabilized zirconia (YSZ) thin films were deposited on polycrystalline non-aligned stainless steel and amorphous glass by unbalanced magnetron sputtering. The mechanism responsible for the specific in-plane alignment has been investigated by carrying out specific depositions. The obtained results led to the proposed growth model. Also the influence of several deposition parameters (target–substrate distance, target–substrate angle and pressure) on the degree of in-plane alignment has been investigated. The degree of in-plane alignment depends on these parameters because they influence the angular spread of the incoming material flux during the deposition. This angular spread of the incoming material flux has been calculated by simulating the transport of sputtered particles through the gas phase. According to the proposed growth model there is a correlation between the calculated angular spread of the material flux and the experimentally observed in-plane alignment.