Dielectric resonance and magnetic properties of Fe-3% doped BaSnO3 thin films grown by pulsed laser deposition

摘要

Fe-3% doped BaSnO3 thin films of good crystalline quality with lattice constant a = 4.053 Å were grown on (2 0 0) n-type Si substrates by pulsed laser deposition. Micro Raman spectra of the thin films showed the presence of strain-induced Raman modes with reference to that of the bulk polycrystalline Fe-3% doped BaSnO3. The films exhibited dielectric resonance in the frequency range 20 – 60 MHz and it is explained qualitatively based on the phenomenon of electromechanical piezoelectric resonance. The measured values of the resonant frequency and the surface resistivity showed a strong dependence on the thickness and the crystalline-character of the thin films. Magnetic measurements were performed selectively for the two films having (2 0 0) preferred orientation. It was found that both of them possess ferromagnetic ordering at 300 K and 1.8 K. At 300 K, the inherent diamagnetism of the undoped BaSnO3 was found to be dominating for higher applied magnetic field.