Fabrication of MIM-GaAs solar cells for high concentration PV

Monolithic integrated modules (MIM) have proven to be effective, large area photovoltaic devices. They were developed for converting high-intensity light in thermo-photovoltaics. Applying this technique to GaAs solar cells opens a new path for low-cost terrestrial photovoltaic energy conversion. Parabolic dishes with a compact receiver area can be used as the concentrating optic. These are well established in the solar-thermal community. First GaAs-MIMs of 1 cm/sup 2/ have been fabricated at the Fraunhofer ISE. The design of the module, the fabrication technology and first results are presented. The electroluminescent light produced under forward bias is used to analyse the modules and locate defects, like shunts. Several shunting defects were observed but they do not affect the performance of the MlM at high concentration levels.