ENERGY-LOSS AND STRAGGLING OF MEV HE-4 IONS IN A SI SB MULTILAYER TARGET/

In a novel approach to energy loss and straggling measurements a multi -delta-layer target of Sb in amorphous Si, grown in a molecular epitax y facility, has been used for Rutherford backscattering experiments wi th He-4 ions. Within the measured energy range of 0.1-4 MeV our stoppi ng power data differ from the values published by Ziegler by up to -10 % around the stopping power maximum at about 0.5 MeV, but tend to merg e at lower and higher energies. The precision is 1% or better. The ene rgy straggling shows an energy dependence from about -20% to +15% with respect to the Bohr prediction.