Study on compositionally graded epitaxial barium strontium titanate thin films derived from pulsed laser deposition

Epitaxial gradient barium strontium titanate (Ba/sub x/Sr/sub 1-x/)TiO/sub 3/ (x=0.75, 0.8, 0.9, 1.0) thin films were prepared by the pulsed laser deposition method on the (La/sub 0.7/Sr/sub 0.3/)MnO/sub 3/ (LSMO)/LaAlO/sub 3/ (LAO) substrate. Their epitaxial structure was characterized via x-ray diffraction (XRD). The gradient change of composition is determined by the energy dispersive X-ray analysis (EDAX). P-E loops were obtained. The dielectric properties in the frequency ranging from 100 Hz to 100 kHz were measured using an impedance analyzer. Results indicated that the epitaxial structure has good dielectric properties.