Tailoring the optoelectronic properties of PZT through the modulation of the thin film

Abstract

Ferroelectric materials have great promise for use in photodetectors due to their built-in electric field-assisted carrier separation and switchable polarization properties. Carrier separation efficiency is a decisive factor in evaluating photodetector performance. The photodetector optoelectronic performance can be enhanced further by optimizing the thickness of the ferroelectric film to take full advantage of the switchable polarization properties of the ferroelectric material, and by enhancing the built-in electric field to drive carrier separation. In this work, we optimize the performance of PbZr0.52Ti0.48O3 (PZT) photodetectors by modulating the thickness of the film. It is observed that thicker ferroelectric films have lower coercivity fields, which are more favorable for ferroelectric domain switching. On this basis, the ferroelectric properties of ferroelectric PZT films were optimized by thickness tuning, and the photodetection performance of PZT-based self-powered photodetectors was explored. It is found that the polarization enhances the internal electric field, driving photogenerated carrier separation and improving the self-powered current, while also selectively enhancing photodetectivity for devices of different thicknesses. Additionally, both film thickness and ferroelectric polarization significantly impact the response time.