Phosphorus Diffusion Mechanisms and Deep Incorporation in Polycrystalline and Single-Crystalline CdTe

Abstract

CdTe solar-cell technology could provide a levelized cost of electricity (LCOE) below that of $a\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}y$ conventional source, including silicon photovoltaics and fossil fuels---if only the open-circuit voltage could be increased. The key is to raise the density of holes, for which phosphorus doping seems promising. A combination of experiment and theory reveals the atomistic mechanisms of P diffusion in CdTe, including fast grain-boundary and bulk diffusion paths. This strong physical insight is needed for next-generation applications, even beyond photovoltaics.