Neo-pentoxide Precursors for MOCVD Thin Films of TiO2 and ZrO2

Two group IV precursors, titanium(IV) neo-pentoxide, [Ti(μ-ONep)(ONep)3]2 (1, where ONep = OCH2C(CH3)3), and zirconium(IV) neo-pentoxide, [Zr(μ-ONep)(ONep)3]2 (2), were found to possess relatively high volatility at low temperatures. These compounds were therefore investigated as metal–organic CVD (MOCVD) precursors using a lamp-heated cold-wall CVD reactor by direct vaporization without a carrier gas. The ONep derivatives proved to be competitive precursors for the production of thin films of the appropriate MO2 (M = Ti or Zr) materials in comparison to other metallo-organic precursors. Compound 1 was found to vaporize at 120 °C with a deposition rate of ∼0.350 μm/min onto a substrate at 330 °C forming the anatase phase with < 1 % residual C found in the final film. Compound 2 was found to vaporize at 160 °C and deposited a crystalline material at 300 °C with < 1 % residual C found in the final film. A comparison with standard alkoxide and β-diketonates is presented where appropriate.