Property improvement of 75 nm-thick directly-crystallized SrBi2Ta2O9 thin films by pulse-introduced metalorganic chemical vapor deposition at low temperature

Crystallized SrBi2Ta2O9 (SBT) films were deposited on (111) Ir/TiO2/SiO2/Si substrates at 650 degreesC by metalorganic chemical vapor deposition (MOCV D). Crystallized SBT films from 75 to 200 mn in thickness were directly dep osited, but its remanent polarization (Pr) decreased when the film thicknes s decreased for the film deposited by conventional continuous-MOCVD. This P r value was increased by 50% by using the source gas pulse-introduction tec hnique (pulse-MOCVD) at 75 nm thicknesses. Moreover, the leakage current wa s dramatically improved to be on the order of 10(-5) A/cm(2) up to 600 kV/c m. This film exhibited strong (103) orientation of the crystal axis, while the continuous gas-introduced film showed a mixture of (001) and (103) orie ntations.