Reduced Leakage Current and Enhanced Photovoltaic Effect in Zn-Doped BiFeO<sub>3</sub> Thin Films
Xinyan Wang, Can Wang, Xiao-Kang Yao, Yong Zhou, Ning Liang, Qiao Jin, Kun Chen, Meng He, Er‐Jia Guo, Chen Ge, Guozhen Yang, Kuijuan Jin
Abstract
Zn-doped BiFeO 3 (BFO) thin films with compositional formula BiFe 1– x Zn x O 3 ( x = 0, 0.1, and 0.2) have been epitaxially grown on SrRuO 3 buffered SrTiO 3 substrates by pulsed laser deposition. The high-concentration Zn doping does not suppress the ferroelectric polarization of the BFO films, and the Zn-doped BFO thin films also show reduced leakage current and an enhanced photovoltaic effect. By optical and photoelectron spectroscopy measurements, with Zn doping, the BFO thin films show more oxygen vacancies and a structural evolution, and moreover, a blue-shift of optical bandgap and an increase of work function are demonstrated. The reduction of leakage current and the enhancement of photovoltaic effect are related to the variation of interfacial Schottky junctions and oxygen vacancies with doping. This study reveals systematic insights into the effects of Zn doping on the physical properties of BFO thin films.