Investigation of Co-Evaporated CIS Thin Films

• Main Authors: Zhao-Yu Ji, 紀昭宇
• Other Authors: Horng-Hwa Lu
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/39627852776594252063

碩士 === 國立勤益科技大學 === 機械工程系 === 98 === CIS is a promising material as absorber in thin film solar cells owing to its direct bandgap and a high absorption coefficient. Cu-In alloy thin films with different Cu/In ratio were deposited by co-evaporation method and post-selenization in a close graphite crucible. The chemical composition, microstructure, electrical, and optical properties were evaluated by EDS, X-ray diffraction, FE-SEM, AFM, Hall measurement, and optical transmission spectroscopy. The results show that CuIn and Cu11In9 phases were observed in Cu-In alloy films. In the indium rich samples, the surface roughness was increased by the formation of island-like grains on the surface. XRD analysis reveal that the copper rich samples after selenide treatment display mainly CuInSe2 phase and few CuSe phase as secondary phase. The grain size of selenized CuInSe2 films at 600℃ with Cu/In atomic ratio of 1.118 was 1-3 μm. The carrier concentration, mobility, absorption, and band gap are 1.9 x 1017/cm3, 4.12 cm2/V‧s, 75%, and 1.0~1.01 eV, respectively. Furthermore, Cu2Se and In2Se3 layers were deposited on glass sequentially and then heat treatment at 600℃ to form CuInSe2 thin films. The chemical composition, microstructure, electrical, and optical properties were also discussed. The X-ray diffraction results showed single phase of CuInSe2 and n-type semiconductive performance. The carrier concentration, mobility, absorption, and band gap are -5.368 x 1021/cm3, 2.254 cm2/V‧s, and 1.028 eV, respectively.