Electrical surface-resistivity, dielectric resonance, polarization and magnetic properties of Bi0.5Sr0.5FeO3-? thin films grown by pulsed laser deposition

Polycrystalline and highly preferred (1 0 2?) orientated Bi 0.5Sr0.5FeO3-? thin films were grown by pulsed laser deposition (PLD) on n-Si (2 0 0) and MgO (2 0 0) single crystalline substrates respectively. The thin films were inspected using x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy and atomic force microscopy techniques. The electrical surface-resistivity, dielectric resonance, electric polarization, and magnetic properties of the thin films were studied. At room temperature, depending on deposition conditions, the polycrystalline thin films grown on n-Si substrates were found to exhibit an electrical surface-resistivity of the order of 103106 ?, a piezoelectric resonance in the frequency range of about 2526 MHz, a relaxor-type ferroelectric hysteresis with a maximum polarization of 0.0150.055?Ccm?2 and magnetic hysteresis. Similarly, the thin films grown on MgO substrates exhibited an electrical surface-resistivity of the order of 109 ?, multiple piezoelectric resonances in the frequency range of about 845 MHz, a linear variation of polarization with applied electric field and either a linearly varying magnetization or magnetic hysteresis which depends on the deposition conditions.� 2014 IOP Publishing Ltd Printed in the UK.