Electron momentum spectroscopy [binary (e,2e) spectroscopy] using transmiss
ion geometry is a unique experimental tool for imaging the electron momentu
m distribution in gas phase samples as well as in thin films. In a solid, t
he electron momentum distribution is related to the band structure. Develop
ment of the (e,2e) technique using a more versatile reflection geometry is
attractive since a much wider range of surfaces could be studied. The desig
n of a new reflection (e,2e) spectrometer is presented. It is based on a tw
o-step scattering model in which an incident electron successively reflects
and ejects a valence electron from the surface. The scattered and ejected
electrons are detected in coincidence and their energies and momentum vecto
rs are simultaneously determined using a high throughput 90 degrees truncat
ed spherical electrostatic analyzer and position-sensitive detectors.