Graded Dielectric Thin Films Prepared by Chemical Solution Deposition

摘要

Columnar structured dielectric (Ba_(1-x)Sr_x)TiO_3thin films with gradients in composition normal to the growthsurface were grown on platinum coated silicon substrates by achemical solution deposition (CSD) method. The compositiongradients were studied by X-ray diffraction analysis and Rutherfordbackscattering spectrometry, and the film morphology was analyzedby scanning electron microscopy. In the graded thin films thediameter of the grain columns as well as the preferred grainorientation can be tailored by the sequence of the layers. Thedielectric properties were analyzed as a function of thecomposition gradiant and the temperature. The temperaturedependence of the capacitance of the graded films, which werecontacted in a plate capacitor setup can be simulated by a networkof (Ba_(1-x)Sr_x)TiO_3 thin film capacitors in series.