A study was made of fitting the donor-acceptor pair luminescence due to P-Al pairs in 4H-SiC. It was possible to identify P at the Si cubic site as the shallower donor with ionization energy of 60.7meV, as well as to distinguish the contribution in the spectrum from pairs involving this donor and Al acceptors from both the cubic and hexagonal lattice sites, leading to justification of their ionization energies. The case of N-Al pair luminescence was revisited and the ionization energy of the deeper Nc donor at the cubic site was determined, 125.5meV.

Ionization Energies of Phosphorus and Nitrogen Donors and Aluminum Acceptors in 4H Silicon Carbide from the Donor-Acceptor Pair Emission. I.G.Ivanov, A.Henry, E.Janzén: Physical Review B, 2005, 71[24], 241201 (4pp)