PHOTOLUMINESCENCE STUDY OF NATIVE DEFECTS IN THE FILLED TETRAHEDRAL SEMICONDUCTOR LIZNP

The radiative recombination related to a native defect in a direct wide-gap semiconductor LiZnP (E(g) = 2.13 eV at 77 K) was studied at 77 K using photoluminescence (PL) technique. One type of crystal yields PL emission that consists of two peaks: One is a peak at 615 nm (2.02 eV) associated with a phosphorus vacancy (lying at 110 meV below the conduction band)-valence band transition and the other a broad peak at 848 nm (1.46 eV) associated with a phosphorus vacancy (V(P))-acceptor complex. Another type of crystal exhibits only a broad emission around 830 nm. Both types of PL emissions are attributed to the difference in concentration between free V(P) defects and V(P)-acceptor complexes in as-grown crystals. The origin of the broad emissions observed in both types is likely to be essentially identical.