Development of InGaAs solar cells for >44% efficient transfer-printed multi-junctions

Transfer-printing is a key enabling technology for the realization of ultra-high-efficiency, mechanically stacked II–IV solar cells with low cost. In this work, we describe the development of InGaAs solar cells, designed to harvest long wavelength photons when stacked in tandem with a high efficiency InGaP/GaAs/InGaAsNSb triple junction solar cell. High performance InGaAs solar cells, grown on InP by MOCVD, were achieved through a combination of detailed modeling, material development and device characterization. The transfer printing apparatus of Semprius Inc. was used to create a four-terminal device with an uncertified conversion efficiency of 44.1% at 690 suns.