Abstract:
We have studied the effect of Er 3+ doping on the dielectric and polarization hysteresis behavior of sol-gel derived Pb 1.05 (Zr 0.53 Ti 0.47 )O 3 thin films. Up to 1 at% Er doping, the dielectric constant of undoped PZT increases from 1245 to 1477 (measured at 50 kHz, 500 mV oscillation voltage), whereas the remnant polarization increases from 30 to 41 w C/cm 2 . Under the subswitching external field, the dielectric permittivities follow the Rayleigh law. The Rayleigh coefficient ( f ) was considered as a measure of the ease of domain wall motion. Up to 1 at% Er doping, the increase of f indicates minimal defect-domain wall interaction due to lower defect concentration. Under the switching field, the irreversible part of the switchable polarization was estimated from the C-V and hysteresis measurements. At the saturation field it was observed that up to 1 at% Er doping the irreversible component at switchable polarization increases and reversible component remains low. The improvements of dielectric and ferroelectric properties for up to 1 at% Er doping have been correlated to the relative site occupancy of Er 3+ as a function of Er content in PZT host lattice.