Structure of InP (001) surfaces prepared by decapping and by ion bombardment and annealing

Abstract

The structure of InP surfaces prepared by ion bombardment and annealing (IBA) and by decapping of InP (001) samples grown by metal organic vapor phase epitaxy is studied. The structural changes of the surfaces during preparation are monitored by low-energy electron diffraction and related to the surface electronic modifications as revealed by reflectance-anisotropy spectroscopy (RAS). For both preparation methods we find (2\ifmmode\times\else\texttimes\fi{}4) reconstructions and almost identical RAS spectra. This finding contrasts with previous reports usually claiming a (4\ifmmode\times\else\texttimes\fi{}2) surface after IBA Auger-electron spectroscopy as well as hydrogen-adsorbate vibrations recorded with high-resolution electron-energy spectroscopy indicate an In-rich surface stoichiometry.