Observation of radiative surface states on InP

Abstract
We have observed radiative surface recombination centers on InP by low-temperature photoluminescence. The luminescence band is observed only after etched or annealed surfaces are treated with hydrofluoric acid (HF), and is not found after rinsing in deionized water. These observations and x-ray photoemission studies of the treated surfaces indicate that the recombination centers are related to the near-surface stoichiometry or to the composition of native oxide layers. The peak energy of the transition has been studied as a function of excitation power and is found to increase from 1.392 eV at low power densities to 1.404 eV and higher power densities.