Thermal Effects in Properties of Photovoltaic Currents of Pb(Zr, Ti)O3 Thin Films

Abstract

Thermal effects in the characteristics of photovoltaic currents of Pb(Zr, Ti)O₃ (PZT) thin films were studied from room temperature up to 360° C. The photovoltaic currents at a steady state increased with increasing temperature and then decreased above 250° C. By conducting annealing for positively or negatively poled samples, the traces of photovoltaic currents gradually became symmetric, suggesting the improvement of crystallinity of PZT thin films and/or the formation of a symmetric pair of Schottky junctions at two interfaces with electrodes. Furthermore, this suggestion was supported by the significant improvement in the characteristics of hysteresis loops upon annealing.