Performance enhancement of III-V compound multijunction solar cell incorporating transparent electrode and surface treatment

To enhance the performance of tandem‐type III–V compound multijunction solar cells, the transparent indium‐tin‐oxide (ITO) film was used to replace conventional metal electrode for increasing the incident light area. For performing ohmic contact between the n‐AlInP window layer and the ITO film, a transition layer of Au/AuGeNi thin metals was used and investigated. Besides, to improve ohmic performance and to passivate the surface states, (NH4)2Sx surface treatment was used. The conversion efficiency of the (NH4)2Sx‐treated triple‐junction solar cells was increased more than 3.09%. Furthermore, an improved oblique SiO2/SiO2/ITO triple antireflection structure was designed to reduce the reflectivity of illuminating sunlight. The conversion efficiency of the (NH4)2Sx‐treated triple‐junction solar cell with improved antireflection structure could be improved more than 4.23%. Simple and effective approaches were designed to improve the performances of tandem‐type III–V triple‐junction solar cells. Copyright © 2010 John Wiley & Sons, Ltd. To enhance the performance of tandem‐type III‐V compound multijunction solar cells, the transparent indium‐tin‐oxide (ITO) film was used to replace conventional metal electrode for increasing the incident light area. For performing ohmic contact between the n‐AlInP window layer and the ITO film, a transition layer of Au/AuGeNi thin metals and (NH4)2Sx surface treatment were proposed and investigated. The conversion efficiency of (NH4)2Sx‐treated triple‐junction solar cell incorporating transparent electrode and improved antireflection structure could be enhanced more than 4.23%.