铁电薄膜光生电流影响因素研究进展

Latest Development in Photo-Induced Current of Ferroelectric Thin Films

铁电光伏效应因其在光电子学、能量转换以及信息存储等方面表现出巨大的潜力而备受关注。与传统的p-n结所不同的是,铁电光伏是一种体效应,光生载流子能在整个材料中被分离开来,光生电压不受禁带宽度的限制,理论上具有较高的光电转换效率。然而,由于其光生电流较低,以至光电转换效率还不够高。弄清影响铁电光生电流的因素是增强其转换效率的重要前提。影响铁电材料光生电流的因素有很多,例如禁带宽度、极化强度、界面势垒、电畴结构、退极化场、氧空位、吸收系数以及晶粒尺寸等。然而,影响铁电材料光生电流的因素目前还没有定论,其机制也一直存在争议。本文综述了铁电薄膜光伏效应的研究进展,详细阐述了影响铁电材料光生电流的各种因素并提出了可能提高光生电流的途径。

The latest progress in the field of photo-induced current of ferroelectric coatings and devices was tentatively reviewed. The discussions focused on：i） its increasingly wide applications in optoelectronics, energycon- version and information storage;ii） the influence of the bulk properties of ferroelectric thin films, including but not limited to the band gap, polarization, barrier height at interface, microstructures of domain, grain size, depolarization field, oxygen vacancies, absorption coefficient, conductivity, and carrier lifetime, on the photo-electric conversion ef- ficiency;ill） the existing technical problems,limiting the separation rate and collection efficiency of the carriers of the ferroelectric coatings, and their engineering solutions via innovative design of novel photovoltaic devices ;iv） the controversial mechanisms responsible for the generation of photo-induced current. In addition, the development trends of the ferroelectric photovoltaic devices were also briefly discussed in a though provoking way.