Abstract
Molecular-beam-epitaxial growth of GaP incorporating isoelectronic N traps was achieved through coinjection of NH 3 and PH 3 which were dissociated into P 2 and PN fluxes. The photoluminescence spectrum of a sample with a N concentration of ∼2×10 19 cm -3 indicated that the dominant emission wavelength was at 5691 Å (2.18 eV), which is characteristic of the nearest-neighbor pair transition NN 1 . The spectrum of a sample containing ∼2×10 20 cm -3 N atoms also displayed strong NN 1 pair luminescence in addition to much stronger emission line at 5846 Å (2.121 eV), which is believed to be from a local mode outside the vibrational band. The peak intensity of this local mode was ∼25 times greater than the peak emission of the NN 1 line from the lighter doped sample.