Microstructure and dielectric properties of barium titanate film prepared by MOCVD

Abstract

Barium titanate (BaTiO3) films were prepared on (100)Pt/(100)MgO substrates by metal-organic chemical vapor deposition (MOCVD). The effects of deposition temperature (Tdep) and O2 partial pressure (PO2) on the microstructure and dielectric properties of the films were investigated. The BaTiO3 films prepared at Tdep 873 K showed a randomly orientated granular structure, while those prepared at Tdep = 973 K showed a significant (001) orientation with a columnar structure. The grain size was strongly affected by PO2 and showed the maximum at PO2 = 66 to 93 Pa. The dielectric constant increased from 93 to 640 with increasing grain size from 20 to 130 nm, showing a broad peak at 350 to 380 K.