Abstract
SrBi2(Ta0.7Nb0.3)2O9 (SBTN) films were first prepared on (111)Pt/Ti/SiO2/Si substrates by MOCVD from only two organometallic source bottles. Bi(CH3)3 and the mixture of Sr[Ta(O°C2H5)6]2 and Sr[Nb(O°C2H5)6]2 were used as source materials. High compositional reproducibility was obtained; the Nb/(Ta+Nb) ratio was the same as the mixing ratio of the source. Sr/(Ta+Nb) and Bi/(Ta+Nb) ratios can be controlled by the reactor pressure and the input gas flow rate ratio of the source gases. Almost single phase of SBTN was obtained for the film deposited at 500°C and the following heat-treated at 800°C in O2 atmosphere. Pr and Ec values of 330 nm-thick SBTN film were 8.5 μC/cm2 and 91 kV/cm, respectively and were larger than those of SrBi2Ta2O9 film. There was no degradation after 5x1010 cycles polarization switching.