太阳电池中CdS多晶薄膜的微结构及性能

Microstructure and Properties of CdS Polycrystalline Thin Films for Solar Cells

采用化学水浴法制备了CdS多晶薄膜 ,通过XRD ,AFM ,XPS和光学透过率谱等测试手段研究了CdS多晶薄膜生长过程中的结构和性能 .结果表明 ,随着沉积的进行 ,薄膜更加均匀、致密 ,与衬底粘附力增强 ,其光学能隙逐渐增大 ,薄膜由无定形结构向六方 (0 0 2 )方向优化生长 ,同时出现了Cd(OH) 2 相 .在此基础上 ,通过建立薄膜的生长机制与性能的联系 ,沉积出优质CdS多晶薄膜 ,获得了转化效率为 13

The properties of CdS thin films prepared by chemical bath deposition (CBD) during the reaction process are studied by XRD,AFM,XPS,and optical transmittance spectra measurements.The results show that as-deposited CdS thin films are more homogeneous,adherent and compact on the glass substrates with time.And the optical band gap values increase too,which relates to the extent of strain.In the early stages of the growth of CBD CdS thin films,they are amorphous.As deposition proceeds,the (002) reflection peak of hexagonal CdS,together with the hexagonal (100) Cd(OH) 2,starts to appear.Furthermore,the CdS thin films show a strong preferential orientation of hexagonal (002) planes,parallel to the substrates surface.Therefore,the properties of the CdS thin films with the growth mechanism are correlated.By optimizing and controlling qualities of CdS thin films in the reaction process,the photovoltaic conversion efficiencies of more than 13% are demonstrated for CdS/CdTe solar cells of 0.502cm 2 under air mass (AM) 1.5 conditions.One of these solar cells reaches the highest conversion efficiency of 13.38% for the domestic polycrystalline thin films solar cells.