UV-O(3) PREPARATION OF INAS (100) SURFACES PRIOR TO MBE GROWTH

InAs (100) surfaces cleaned by the UV-ozone method or by Br-MeOH etchi ng were annealed under an As flux. By Auger electron spectroscopy (AES ) and reflection high energy electron diffraction (RHEED), we compare the quality of these surfaces before and after annealing. We show that the UV-ozone process, unlike Br-MeOH etching, produces a capping oxid e which desorbs. We study this desorption as a function of temperature and show that, at 510-degrees-C, the layer is removed. The surface is then oxygen and carbon free. It is therefore more appropriate for gro wth than the surface obtained by Br-MeOH etching, which is always cont aminated by carbon.