Structural and electrical properties of double-layer ceria/yttria stabilized zirconia deposited on silicon substrate

Analyses of the phase composition and electrical characterization of double-layer CeO2/YSZ and single-layer CeO2, YSZ dielectrics grown on a Si (100) substrate at 200 degrees C by electron beam evaporation as well as of the quality of interfaces between the oxide layers and silicon substrates were performed. The structure of all investigated oxide layers was found to be of the fee fluorite type. The electrical conductivity of the investigated oxide layers and the average grain size change due to the post-deposition thermal treatment. The temperature dependence of the activation energy of the electrical conductivity is associated with different impurity phases in the oxide layers. Due to the lowest density of defects assessed from deep-level-transient-spectroscopy (DLTS) measurements, the CeO2/Si interface seems to be an optimum compared to the other oxide layer configurations. The dielectric constants epsilon(r)(YSZ) = 18.3 and epsilon(r)(CeO2) = 3.4 were estimated from the accumulation capacitances of the C-V curves. (C) 1999 Elsevier Science B.V. All rights reserved.