Ion-induced electron measurements using crystal targets overlaid with noncrystalline layers

We have measured continuum electron yields from Si crystals covered with no ncrystalline Si layers of 150-350 Angstrom thicknesses using 8.0 MeV/u H+ a nd He2+. These layers provide unshadowed subsurfaces from which target elec trons are recoiled under channeling incidence conditions. The production an d escape processes of the electrons can be well understood using a few quan tities determined from these experiments. The present experimental approach allows general understanding of the continuum electron spectra from solid targets. (C) 2000 Elsevier Science B.V. All fights reserved.