Structure analysis of CsCl deposited on the MgO(001) surface by coaxial impact collision atom scattering spectroscopy (CAICASS)

CsCl films deposited on the MgO(001) surface were investigated using coaxia l impact collision atom scattering spectroscopy which has been developed in the present study, in addition to reflection high-energy electron diffract ion and atomic force microscopy. In the initial stage of the growth, the co existence of alpha- and beta-CsCl phase with their (001) parallel to the su rface has been found. The orientation relationship of each phase was determ ined. By contrast, the thick film in the range between 100 and 200 Angstrom consisted of alpha-CsCl with its (110) parallel to the surface, The struct ural transition from the former to the latter structure was observed to occ ur on annealing of the overlayer of 10-30 Angstrom at 673 K for 10 min. The CsCl growth on MgO at room temperature is thought to occur in the Volmer-W eber mode. In the present investigation, the problem of the charging effect was succes sfully avoided. CAICASS has been shown to be a powerful technique for the s tructure analysis of insulator surfaces. (C) 1999 Elsevier Science B.V. All rights reserved.