Ultrasonic mist chemical vapor deposition and dielectric properties of cubic pyrochlore bismuth magnesium niobate thin films

Abstract

Ultrasonic mist chemical vapor deposition (mist-CVD) process has been used to deposit bismuth-based cubic pyrochlore thin films for the first time. The crystal structure, morphology, and dielectric properties of Bi1.5MgNb1.5O7 (BMN) films grown in N2, air, and O2 carrier gas are characterized. Sufficient O2 is beneficial for the pure phase and highly crystallized cubic pyrochlore BMN thin films with a (2 2 2)-preferred orientation. Superior dielectric properties (dielectric constant 176, loss tangent 0.005, and tunability 29%@ ∼1 MV cm−1) at 1 MHz are obtained. The results suggest that the mist-CVD method have potential in depositing high quality bismuth-based cubic pyrochlore thin films.