Metalorganic chemical vapour deposition (MOCVD) of zirconia and lead zirconate titanate using a novel zirconium precursor

Abstract

The novel mixed ligand precursor Zr 2(OPr i) 6(thd) 2 (thd=2,2,6,6,-tetramethyl-3,5-heptanedionate) has been used in the deposition of ZrO 2 and Pb(Zr,Ti)O 3 thin films by liquid injection metalorganic chemical vapour deposition (MOCVD). Oxide growth was observed over a wide temperature range, from 250°C to at least 600°C. Maximum growth rates of ZrO 2 occurred between 350°C and 550°C, significantly lower than the optimum deposition temperature from the conventional Zr(thd) 4 precursor, and in a similar temperature range to optimised oxide growth from Pb(thd) 2. Consequently, the use of Zr 2(OPr i) 6(thd) 2 in combination with Pb(thd) 2 and Ti(OPr i) 2(thd) 2 leads to the deposition of Pb(Zr,Ti)O 3 with improved compositional uniformity.