Abstract:

Conductive perovskite-type BaPbÛ3 thin films were deposited onto Al₂O₃ substrates by a modified sol-gel method , using ethylene diamine tetra-acetic acid , citric acid and tartaric acid as the complex chelating agent and with water as the solvent. Then , the effects of heat treatment and temperature on the chemical composition and sheet resistance of the prepared films were investigated by XRD , EDXS and sheet resistance measurements. The results show that , in contrast with the conventional thermal annealing , the rapid thermal annealing technique requires higher annealing temperature to synthesize the BaPbO₃ phase and , at the same time , the molar ratio of Pb to Ba decreases with the increase of annealing temperature , which results in the increase of sheet resistance of BaPb03 thin films. Moreover , by the conventional thermal annealing technique , BaPbO₃ films with a sheet resistance of 32Ω/ 口and a thickness of 2. 5μm can be obtained by means of annealing at 670℃ for 10 min.

Key words: barium plumbate, thin film, sol-gel method, heat treatment, chemical composition, sheet resistance