SrBi 2Ta 2O 9 thin films grown by MOCVD using a novel double metal alkoxide precursor

Abstract

We have investigated the growth of Bi oxide, Sr–Ta oxide, and SrBi 2Ta 2O 9 (SBT) thin films on Pt/SiO 2/Si substrates by the MOCVD technique using a novel double metal alkoxide precursor, strontium and tantalum ethoxide (Sr[Ta(OEt) 6] 2), and triphenylbismuth [Bi(C 6H 5) 3]. SBT films having ternary compositions were grown over a 500–700°C temperature range with polycrystalline films being attained after annealing at 800°C in oxygen. β-Bi 2O 3 phase was obtained after annealing as-grown films at 800°C in oxygen. Sr–Ta oxide films grown at 500°C substrate temperature had SrTa 2O 6 phase, which may be appropriate for growing SBT films having perovskite layer (SrTa 2O 7). Details of obtaining the necessary flow ratios of the two precursors are given along with SEM micrographs of the polycrystalline SBT film.