No abstract

The electronic structure of the epitaxial GaN, InN nanolayers, and the ultrathin Cs/GaN and Cs/InN interfaces was investigated under ultrahigh vacuum at various Cs coverages. The experiment was carried out using synchrotron‐based photoelectron spectroscopy. The photoemission spectra of the valence band and the In 4d, N 2s, Ga 3d, and Cs 4d semicore levels were studied as a function of Cs coverages. It was found that the Cs adsorption in the submonolayer coverage region causes substantial changes in the spectra due to charge transfer between the Cs adlayer and surface Ga or In atoms. The strong interaction of the dangling bonds of Ga or In with Cs adatoms effectively increases the Ga or In valency.

The electronic structure of the clean AlN surface and the ultrathin K/AlN interface has been studied in situ by synchrotron-based photoelectron spectroscopy using the photon energies in the range of 100-650 eV. The effect of K adsorption was studied. Changes in the valence band and in the Al 2p, N 1s, and K 3p core levels spectra have been investigated using K submonolayer deposition. Modification of the surface electronic structure of the AlN caused by K adsorption is found to originate from the local interaction of N surface atoms and K adatoms. As a results the suppression of intrinsic surface state and appearance of a new induced state are observed. It was found the K-induced electron redistribution effect that causes the positive energy shift of N 1s surface peak and increasing N-ionicity. Keywords: III-nitrides, electronic structure, surface states, metal-III-nitride interfaces, photoelectron spectroscopy.

No abstract

The electronic structure of the clean AlN surface and the ultrathin K/AlN interface has been studied in situ by synchrotron-based photoelectron spectroscopy using the photon energies in the range of 100-650 eV. The effect of K adsorption was studied. Changes in the valence band and in the Al 2p, N 1s, and K 3p core levels spectra have been investigated using K submonolayer deposition. Modification of the surface electronic structure of the AlN caused by K adsorption is found to originate from the local interaction of N surface atoms and K adatoms. As a results the suppression of intrinsic surface state and appearance of a new induced state are observed. It was found the K-induced electron redistribution effect that causes the positive energy shift of N 1s surface peak and increasing N-ionicity. Keywords: III-nitrides, electronic structure, surface states, metal-III-nitride interfaces, photoelectron spectroscopy.