Plasma enhanced chemical vapour deposition of ZrO 2 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.