Development of a robust and high efficiency concentrator receiver

One of the difficulties in development of concentrator receiver using III-V solar cells is realization of robust structure with capable of high current density. Most of the cases, the top electrodes were cabled by wire bonding, conductive epoxy and silver ribbon blazing, which gradually increases series resistance under severe environment and loses reliability. Extending the MJ cell performance envelope to the economically required higher current levels and higher current density levels has involved serious and unexpected challenges. A new and robust concentrator receiver was developed with capable of more than 500X of concentration. A 6300 cm/sup 2/ and 400X concentrator module were fabricated with the new receivers. The average efficiency in clear day was 21.7%.