Evidence for Phosphorus on Carbon and Silicon Sites in 6H and 4H SiC

New lines are observed in the photoluminescence of 6H and 4H SiC epitaxial layers grown in cold wall CVD reactors and doped with phosphorus. These lines are associated with neutral phosphorus donor four particle bound exciton complexes with the phosphorus substituting on both the carbon and silicon sublattices. Assignments are made for the (h) hexagonal and (k) cubic sites of the phosphorus donor substituting on the two SiC sublattices.