Method of depositing a thermal barrier coating

A process of forming a thermal barrier coating on a gas turbine engine component, the process comprising the steps of:

• forming a bond coat on a surface of the component;
• placing the component in a coating chamber containing oxygen and an inert gas;
• heating a surface of the component to a temperature of about 100° C. to about 150° C.;
• generating a metal vapor from multiple zirconium-containing metal targets using a microwave-stimulated, oxygen-containing sputtering apparatus;
• condensing the metal vapor on the surface to form a metal layer;
• and
• treating the metal layer with a microwave-stimulated plasma to cause diffusion-limited oxidation of the metal layer and form a columnar oxide layer comprising substoichiometric zirconia;
• wherein the generating, condensing and treating steps are repeated to form multiple oxide layers that together constitute the ceramic coating.