A NOVEL ANALYSIS SYSTEM OF SYNCHROTRON-ORBITAL-RADIATION-LIGHT INDUCED PHOTOEMISSION COUPLED WITH ION-SCATTERING - SORI

We designed and constructed a novel analysis beam line connected to a 575 MeV electron synchrotron with a superconducting magnet working at the Ritsumeikan University. It allows synchrotron-orbital-light induce d photoemission and medium energy ion scattering spectroscopy under ul trahigh vacuum conditions and thus enables us to determine the electro nic states and atomic configurations of surfaces and interfaces for va rious materials. Samples are prepared by molecular beam epitaxy and ca n be analyzed in situ by the above spectroscopy without exposing them to the air. The optical system consists of a cylindrical mirror for co llection of the synchrotron radiation-light, a couple of plane mirrors for deflection and a varied-space plane grating as a monochromator an d a toroidal mirror for focusing the monochromated light on a sample. Exchange of the varied-space plane grating monochromators of different line densities covers the photon energies from 5 up to 700 eV and the resolution (Delta E/E) is estimated to be better than 6 x 10(-4). Pho toelectrons are detected with a hemispherical energy analyzer with a r adius of 139.7 nun. A new toroidal electrostatic analyzer was designed and fabricated to realize a layer-by-layer analysis using medium ener gy ion scattering. A wide interelectrode distance of is mm covers a wi de energy range, W( = 0.1 x E-0, where E-0 is the energy of ions defle cted along a central curvature) at a fixed applied voltage and thus re duces the acquisition time without lowering the statistics. This paper represents the preliminary data obtained so far concerning surface hy drogen detection and surface relaxation of TiO2-terminated SrTiO3 (0 0 1). (C) 1998 Elsevier Science B.V.