中文摘要：

CdS-CdTe铁电半导体耦合太阳能电池是一种新型太阳能电池,其工作机理是光伏材料Cd Te吸收光子产生的电子空穴对,在铁电材料Cd S极化形成的内建电场作用下向两极运动,通过前后电极引出形成电流.本文利用原子力显微镜（AFM）进行导电AFM扫描,得到的Cd S-CdTe铁电半导体耦合太阳能电池薄膜表面微观电流分布出现了一些反常的现象,Cd Te晶粒边界处存在百纳米级别的小颗粒覆盖晶界,晶界不导电,大电流区域沿晶界边缘在晶粒内分布.作为对比,同样条件下制得的纯CdTe薄膜晶界却存在明显的导电现象.在进行导电AFM扫描时,分别对两组薄膜样品施加方向相反的直流偏压,发现Cd S-Cd Te铁电半导体耦合太阳能电池薄膜晶界处存在明显的压电现象,证明Cd S-CdTe铁电半导体耦合太阳能电池薄膜中不导电晶界很有可能是具有压电性的富S的Cd S（1-x）Tex颗粒.扫描透射电镜分析也证实了这些小颗粒为六方相富S的Cd S（1-x）Tex合金.同时,经过六个月的定期测试,发现CdS铁电半导体耦合太阳能电池出现效率增长的异常现象,最高电池效率已达13.2%,该效率是目前已知的铁电光伏器件中最高的.

英文摘要：

In recent years,a variety of new-concept solar cells have attracted the attention of many scholars.The Cd S-Cd Te ferroelectric–semiconductor coupled（FSC） solar cell is a novel concept of photovoltaic device that is designed with ferroelectric nano particles of S-rich Cd S（1-x）Tex,which are embedded in the light-absorbing semiconductors of Te-rich Cd SyTe（1-y）.In our previous work,we have developed a two-step process to fabricate a nano-dipole photovoltaic device,including a thin film deposition in vacuum and high-temperature phase segregation at elevated temperature in sequence.The X-ray diffraction（XRD） and high-resolution scanning transmission electric microscopy（STEM） results confirm the formation of S-rich Cd S（1-x）Texparticles with a wurtzite structure embedded in a Te-rich Cd SyTe（1-y）film with a zinc blend structure.The localized ferroelectric hysteretic behavior of these particles is confirmed through piezoelectric force microscopy.Meanwhile,a set of Cd S-Cd Te FSC devices with a symmetrical structure of ITO/FSC/ITO is fabricated.We observe not only a reasonable photovoltage output on the order of hundreds of mV but also the hysteretic behavior of photovoltage through external electric field post-fabrication.To search for direct evidence of the working mechanism of the FSC solar cell,we further study the film surface micro current distribution of the FSC thin film solar cell.In this work,we adopt the CAFM method to acquire electron distribution of the FSC thin film surface and STEM,the electron diffraction for element distribution,and crystal structure of FSC thin film.Also,Schottky solar cell of FTO/pure Cd Te/metal structure which is fabricated by the same process as the FSC solar cell is used as reference sample in the CAFM analysis.In this work,we fabricate the Cd S-Cd Te FSC film solar cell through a radio-frequency magnetron sputtering method,whose structure is a glass/FTO/Cd STe/back contact（Cu/Au） configuration.In order to enhance the polarization of nano dipole