Deep level transient spectroscopy characterization of BaSi2 light absorbers

In this study, we investigated defect levels and their densities by deep-level transient spectroscopy (DLTS). In BaSi 2 epitaxial films, there is a hole trap with a density of N T = 1013 cm−3 at 0.27 eV from the valence band edge. This is interpreted to originate from Si vacancies. We also discuss the minimum lifetime of BaSi2 from the viewpoint of the Shockley-Read-Hall recombination model.