Electrical properties of LaB6/PZT/Ag structure with asymmetric interface charge distribution

摘要

Effect of the bottom electrode (LaB6) on electron emission characteristics (current density, excited voltage), leakage current behavior and polarization-voltage hysteresis of the Ag/PbZr0.52Ti0.48O3/LaB6/Al2O3 capacitor has been firstly experimentally investigated by fabricating PbZr 0.52Ti0.48O3 (PZT) and LaB6 films with sol-gel and e-beam evaporation techniques respectively. The current-voltage (I-V) and hysteresis (P-E) characteristics show different charge distribution at the top and bottom interfaces. Leakage current behavior as a function of voltage is interpreted by Schottky charge transport mechanism. Electron emission from the PZT surface under low driving pulses <0.4 V has been detected in vacuum chamber with pressure 4x10-5 Torr. Current densities in the range of 0-105 μA/cm2 have been measured in a diode configuration under 10-22 kV/cm excitation voltages and compared with data reported in the literature.