PHOTO INDUCED CURRENT IN (Pb0.97La0.03) (Zr0.52Ti0.48)O3THIN FILMS OF DIFFERENT THICKNESSES

ABSTRACT Photovoltaic effect in ferroelectric materials exhibits potential for applications of sensors and remote controls in micro-electro-mechanical systems, and a systematic evaluation on the photovoltaic behavior in ferroelectric materials becomes important. However, as a critical parameter that determines the photovoltaic output in ferroelectric thin films, the film thickness effect on photocurrent output has not been investigated for thin film samples. In this work, a theoretical model has been developed to describe the thickness-dependent photocurrent in (Pb0.97La0.03)(Zr0.52Ti0.48)O3(PLZT) thin films with a sandwich electrode structure. This model indicates that photocurrent increases exponentially with the decrease in film thickness. Therefore, a significantly enhanced photocurrent can be expected in thinner PLZT films. The predicted thickness dependence of the short circuit photocurrent was also supported by our experimental results.