γ-Ray Total Dose Radiation Effects of Pt/PbZr_0.52Ti_0.48/Pt and Au/PbTiO₃/YBa₂Cu₃O_7-δ Ferroelectric Capacitors

In order to investigate the total dose radiation effects of ferroelectric (FE) capacitors, Pt/PbZr_0.52Ti_0.48O₃/Pt (Pt/PZT/Pt) and Au/PbTiO₃/YBa₂Cu₃O_7-δ (YBCO) capacitors were fabricated by pulsed excimer laser deposition (PLD) on Si(100) and SrTiO₃(001) substrates, respectively. The capacitance-voltage (C-V) curve and hysteresis loops properties of the capacitors were measured before and after γ-ray irradiation. The results show that, with the increment of the total dose, the remanent polarization and the coercive field of the PZT capacitors did not decrease, but increased while the dielectric constant ε decreased; the degradation of the ε of the PbTiO₃ capacitors is similar to that of the PZT capacitors, but the remanent polarization and the coercive field decreased gradually. The results have been interpreted by radiation-induced positive charges and the traps of defects theory.