Hydrogen-induced degradation in ferroelectric Bi3.25La0.75Ti3O12

Effects of forming gas annealing (FGA) were investigated on ferroelectric Bi3.25La0.75Ti3O12 (BLT) thin films fabricated by a chemical solution deposition. With the FGA up to 350 degreesC, the Pt/BLT/Pt capacitors showed good ferroelectric characteristics without significant degradation. As the FGA temperature was increased, a decomposition of the BLT powder sample was observed by using thermogravimetric analysis. By comparing the time-dependent weight loss of BLT with that of Bi4Ti3O12 during FGA, La doping was found to significantly impede the decomposition rate. The decomposition, especially in the (Bi2O2)(2+) layers, was discussed as a hydrogen-induced degradation mechanism in the Bi-layered perovskite ferroelectrics. (C) 2002 American Institute of Physics.