Final Report for PV Incubator Subcontract No. NEU-0-99010-09: March 29, 2010 - March 28, 2011

MicroLink has developed a process technology that will enable the manufacture of high-efficiency, low-cost, multijunction solar cells for use in concentrating photovoltaic (CPV) applications. The multijunction cells were fabricated using a novel low-temperature wafer bonding process. A triple-junction InGaP/GaAs/Ge tandem solar cell with efficiency of 30% at 1 sun AM1.5 illumination wasfabricated by wafer bonding a dual-junction InGaP/GaAs cell to a single-junction Ge cell. Temperature cycling over the range -25 degrees C to +40 degrees C resulted in no degradation of cell performance. Triple junction InGaP/GaAs/Ge cells were mounted onto ceramic carriers and tested at concentrations up to 300 suns.