ABSTRACT
III-V photovoltaics (PVs) have demonstrated the highest power conversion efficiencies for both single- and multi-junction cells. However, expensive epitaxial growth substrates, low precursor utilization rates, long growth times, and large equipment investments restrict applications to concentrated and space photovoltaics (PVs). Here, we demonstrate the first vapor-liquid-solid (VLS) growth of high-quality III-V thin-films on metal foils as a promising platform for large-area terrestrial PVs overcoming the above obstacles. We demonstrate 1-3â µm thick InP thin-films on Mo foils with ultra-large grain size up to 100â µm, which is ~100 times larger than those obtained by conventional growth processes. The films exhibit electron mobilities as high as 500â cm²/V-s and minority carrier lifetimes as long as 2.5â ns. Furthermore, under 1-sun equivalent illumination, photoluminescence efficiency measurements indicate that an open circuit voltage of up to 930â mV can be achieved, only 40â mV lower than measured on a single crystal reference wafer.