Plasma enhanced chemical vapour deposition of ZrO2 and YSZ coatings

Abstract

YSZ coatings can prevent deleterious thermal effects on thermolabile alloys, however, a challenge is their deposition with a cubic phase at temperatures below 800 °C. In this work, PE-CVD was used to deposit ZrO2 and YSZ coatings at ∼700 °C, by varying the evaporation temperature, the vol.% O2, and the substrate position. Our results showed that an evaporation temperature of 200 °C was needed to deposit ZrO2 coatings. At 700 °C, the tetragonal phase was favoured regardless of the position within the heating zone. At 800 °C with a content of 20–60 vol.% O2, monoclinic and tetragonal structures were predominant, probably due to an increase in the crystallite size. When the ZrO2 was dopped with Y2O3, a fully cubic structure of ZrO2 was deposited.