Photon Management in CdSeTe Absorber Solar Cells: The Case for Increased Attention to Optical Cell Design

It is well known in mature technologies that smart optical design in solar cells is essential to approaching the detailed balance limit. In CdTe, the SRH recombination that was limiting the radiative efficiencies (both internal and external) is slowly being reduced to levels at which the contribution to recombination from that which is radiative in nature is non-negligible. As such, it is important to start considering the effects of photon management since the re-absorption of photons becomes increasingly feasible. Here we model the implied voltage of absorbers with different back reflectance and demonstrate that real absorbers are now within the range where optical considerations are needed to achieve the highest possible voltages.