A protective capping procedure has been used to prepare surfaces of MBE-grown InAs(001) for HREELS and photoemission studies. The comparison between photoemission and infrared transmission spectra demonstrates that at a bulk doping level of 8 × 1018 cm3, the Fermi level at the surface coincides with that in the bulk. This allows observation of the effects of spatial dispersion in the surface plasmon mode in HREEL spectra. © 1992.
