Effect of Deposition Temperature and Composition on the Microstructure and Electrical Property of SrBi₂Ta₂O₉ Thin Films Prepared by Metalorganic Chemical Vapor Deposition

Abstract

SrBi 2 Ta 2 O 9 (SBT) thin films were prepared by conventional thermal metalorganic chemical vapor deposition (MOCVD) and subsequent heat treatment. The SBT film deposited at 500°C had a smoother surface and better step coverage than that deposited at 750°C. The degree of step coverage deposited at 500°C was 0.82. An almost single phase of SBT was obtained for the film with a Bi/Ta mole ratio of 1.0 by heat treatment at 750°C for 30 min in O 2 atmosphere after MOCVD deposition at 500°C. 2 P r and E C at an applied electric field of 620 kV/cm were 12.2 µC/cm 2 and 87 kV/cm, respectively, when the film was deposited at 500°C followed by heat treatment at 800°C for 30 min in O 2 atmosphere, and its Bi/Ta ratio was 1.2.