Versatile apparatus for low-energy and hyperthermal energy ion scattering spectroscopies

We have designed and constructed an apparatus that combines hyperthermal energy ion scattering (<100 eV) with low-energy ion scattering (a few hundred eV to several keV). The UHV scattering chamber possesses a full range of sample preparation and characterization capabilities, including LEED, Auger spectroscopy, a Kelvin probe for work function measurements, and facilities for gas or alkali-metal deposition. The differentially pumped beamline provides well-collimated, monoenergetic beams of gas or alkali-metal ions ranging in energy from <10 eV to 10 keV. To illustrate the qualitative changes in the scattering behavior observed over this range, we present experimental results for Na+ scattered off the Cu(110) surface with the incident ion energy ranging from 56 eV to 4 keV. We also show a comparison between 1 keV K+ and 1 keV Ar+ scattered from the same surface.