Stability of SnO2/Fe2O3 multilayer thin film gas sensor

Abstract SnO 2 /Fe 2 O 3 multilayer thin film was prepared by sol-gel technique and analyzed by scanning electron microscopy (SEM), transmission electron miscroscopy (TEM), and atomic emission spectroscopy (AES). The gas-sensitive characteristics of the SnO 2 /Fe 2 O 3 multilayer thin film was investigated. The SnO 2 /Fe 2 O 3 thin film exhibited improved selectivity and stability, but slightly reduced sensitivity, compared with SnO 2 and Fe 2 O 3 thin films. The existence of an interfacial transition layer between the SnO 2 layer and the Fe 2 O 3 layer and the stabilization mechanism of the SnO 2 /Fe 2 O 3 multilayer thin film are discussed.