Ferroelectric characteristics of Au/PbTiO3/YBa2Cu3O7-δ and Au/PbZr0.52Ti0.48O3/YBa2Cu3O7-δ capacitors in a radiation environment

PbTiO3/YBa2Cu3O7-delta (PTO/YBCO) and PbZr0.52Ti0.48O3/YBa2Cu3O7-delta (PZT/ YBCO) structures were fabricated on SrTiO3 and LaAlO3 substrates by the pulsed excimer laser deposition (PLD) method, respectively. In order to investigate total dose radiation effects on the Au/PTO/YBCO and Au/PZT/YBCO fenoelectric (FE) capacitors, the capacitance-voltage (C-V) and the retained polarization properties of the capacitor were measured before and after gamma-ray irradiation. The results showed that, with the increment of the gamma dose, the retained polarization Delta P and the dielectric constant epsilon of the FE capacitors decreased; but the absolute value of the negative and positive coercive fields of the PZT capacitor increased while that of the PTO capacitor decreased. The results have been interpreted by radiation-induced positive charges and the defect trap model.