Photovoltaic effect of ferroelectric Pb(Zr0.52,Ti0.48)O3 deposited on SrTiO3 buffered n-GaAs by laser molecular beam epitaxy

Abstract

Ferroelectric Pb(Zr[Formula: see text],Ti[Formula: see text]O3(PZT) thin film was grown on [Formula: see text]-type GaAs (001) substrate with SrTiO3 (STO) buffer layer by laser molecular beam epitaxy (L-MBE). The epitaxial process of the STO was in situ monitored by reflection high-energy electron diffraction (RHEED). The crystallographical growth orientation relationship was revealed to be (002) [Formula: see text] PZT//(002) [Formula: see text] STO//(001) [Formula: see text] GaAs by RHEED and X-ray diffraction (XRD). It was found that a small lattice mismatch between PZT and GaAs with a 45[Formula: see text] in-plane rotation relationship can be formed by inserting of a buffer layer STO. Besides, the enhanced electrical properties of the heterostructure were obtained with the short-circuit photocurrent increased to 52[Formula: see text]mA/cm2 and the better power conversation efficiency increased by 20% under AM1.5[Formula: see text]G (100[Formula: see text]mW/cm[Formula: see text] illumination. The work could provide a way for the application of this kind of heterostructure with high photocurrent response in optoelectronic thin film devices.