CdTe-HgCdTe叠层太阳电池CdS窗口层透射光谱性能研究

Optical transmittance properties for CdS films in CdTe-HgCdTe tandem solar cells

CdS窗口层光谱透射率的提高对cdTe-HgCdTe叠层太阳电池有效利用入射太阳光并增大电池的短路电流密度有重要的影响。通过研究化学水浴法、近空间升华法和磁控溅射法制备的CdS薄膜在CdCl2退火前后的光谱平均透过率和短路电流密度损失表明：在光谱区520-820nm，化学水浴法制备的CdS薄膜在退火前后具有最高的光谱平均透过率，对应的CdTe顶电池有最小的短路电流密度损失；在光谱区820—1150和520-l150nm，磁控溅射法制备的CdS薄膜在退火前后均具有最高的光谱平均透过率，对应的HgCdTe底电池和CdTe-HgCdTe叠层太阳电池有最小的短路电流密度损失。在光谱区520—820、820—1150和520-1150nm，CdCl2退火可以显著增大cds薄膜的光谱平均透过率，降低对应CdTe顶电池、HgCdTe底电池和CdTe-HgCdTe叠层电池的短路电流密度损失。

Improving the spectral transmittance of CdS window layer used in CdTe-HgCdTe tandem solar cells has a significant impact on the effective utilization of sunlight and increases the device short-circuit current density（Jsc）. Herein, the average transmittance（T） and Jsc losses of as-deposited and CdCl2 annealed CdS films prepared by chemical bath deposition（CBD）, near space sublimation（CSS） and magnetron sputtering（SPUT） are studied. The results show that： in the range of 520-820 nm, the as-deposited and annealed CdS films by CBD exhibit the highest T and the lowest Jsc losses of the CdTe top cell; in the range of 820-1 150 and 520-1 150 nm, the as-deposited and annealed CdS films by SPUT exhibit the highest T and the lowest Jsc losses of the HgCdTe bottom cell and the CdTe-HgCdTe tandem solar cells. In the range of 520-820, 820-1 150 and 520-1 150 nm, the CdCl2 annealing can greatly increase T of CdS films and decrease the Jsc losses of the CdTe top cell, the HgCdTe bottom cell and the CdTe- HgCdTe tandem solar cells.