%0 Journal Article
%T Sub-Bandgap Luminescence from Doped Polycrystalline and Amorphous Silicon Films and Its Application to Understanding Passivating-Contact Solar Cells
%J -
%D 2018
%R https://doi.org/10.1021/acsaem.8b01561
%X We report luminescence phenomena from doped polycrystalline silicon (poly-Si) films and their applications to study carrier transport properties in passivating-contact solar cells. Low-temperature luminescence spectra emitted from doped poly-Si layers are found to be very broad and stretched from the crystalline silicon (c-Si) luminescence peak to significantly lower energies. This suggests that these layers contain radiative defect levels whose energies are continuously distributed from the band edges to deep levels in the poly-Si bandgap. Moreover, photoinduced carriers inside poly-Si layers are found to be completely blocked by an ultrathin SiOx interlayer (กซ1.3 nm). This demonstrates that there is no free-carrier coupling from poly-Si layers in practical passivating-contact solar cells. Finally, we demonstrate that the same principle can be applied to study carrier transport properties in hydrogenated amorphous silicon films
%U https://pubs.acs.org/doi/10.1021/acsaem.8b01561