CdTe薄膜太阳电池背接触的研究

用近空间升华法制备了CdTe多晶薄膜，用硝酸-磷酸(NP)混合液对薄膜表面进行了腐蚀.经SEM观测，腐蚀后的CdTe薄膜晶界变宽，XRD测试发现，经NP腐蚀后，在CdTe薄膜表面生成了一层高电导的富Te层.在腐蚀后的CdTe薄膜上分别制备了Cu，Cu/ZnTe：Cu，ZnTe：Cu，ZnTe/ZnTe：Cu四种背接触层，比较了它们对太阳电池性能的影响.结果表明，用ZnTe/ZnTe：Cu复合层作为背接触层的效果较好，获得了面积为0.5cm²，转换效率为13.38%的CdTe多晶薄膜太 关键词： 硝磷酸腐蚀 背接触层 CdTe太阳电池

A study of back contacts of CdTe thin film solar cells

We have prepared polycrystalline CdTe thin films by close-spaced sublimation，then the film surface was been etched by nitric-phosphoric acid. After etching，the grain boundaries of CdTe thin films are broadened and it could be seen clearly that the surface became polished and more smooth, when observed by scanning electron microscope (SEM). After NP etching，highly conductive Te-rich layer is formed on the surface of CdTe thin film，as detected by X-ray diffraction (XRD). Four types of back-contact layers, including Cu, Cu/ZnTe：Cu, ZnTe：Cu and ZnTe/ZnTe：Cu were deposited respectively on the etched CdTe thin film，and the influences on the solar cells performance were compared. Our studies showed that the performance of CdTe solar cells with ZnTe/ZnTe：Cu complex back-contact layer was better than those with other back-contact layers，and the highest conversion efficiency of 13.38% has been obtained for CdTe polycrystalline thin film solar cells of 0.5cm² size.