Preparation of zirconia thin films by metalorganic chemical vapor deposition using ultrasonic nebulization

Zirconia (ZrO₂) thin films were prepared by metalorganic chemical vapor deposition (MOCVD) using ultrasonic nebulization with new source materials, Zr(OBu)₄, Zr(OBu)₃(acac), Zr(OBu)₂(acac)₂, and Zr(OBu) (acac)₃. This process is a simple and economic method to prepare oxide thin films. Zr(OBu)₄ was successfully reacted with acetylacetone at a molar ratio of 1: 3. Polycrystalline thin films were deposited at a substrate temperature range from 300 to 550 °C. The substitution of alkoxy radicals by acetylacetone made the deposition rate higher and insensitive to substrate temperature. The films deposited below 450 °C mostly had a monoclinic structure, and those deposited above 450 °C had a tetragonal structure. The measured optical energy band gap of zirconia film was 5.32 eV.