Optical identification and electronic configuration of tungsten in 4H- and 6H-SiC

This report suggests that UD-1 is Tungsten related, based on a doping study and previously reported deep level transient spectroscopy data, as well as photo-induced absorption measurements. The electronic levels involved in the optical transitions of UD-1 are also deduced. The transitions observed in the photoluminescence of UD-1 are from a Γ4C3v, to two different final states, which transform according to Γ5C3v⊕Γ6C3v and Γ4C3v, respectively.