Abstract
A combined ion-scattering and secondary-ion mass spectrometer, for use in studies of low-energy ion bombardment of solids, is described. The secondary ions from the target (both sputtered and scattered) are analysed by a momentum analyser having a 14 cm radius and 90 degrees magnetic sector which provides their positive identification in mass and energy. It is an ultrahigh-vacuum instrument; inert-gas primary ions of energies in the range 15-2000 eV are used. The principle of operation, constructional details and capabilities are presented. The use of the instrument in secondary-ion mass spectrometry and ion-scattering studies is discussed. The magnetic analysis used allows the sputtered and scattered ions to be distinguished even at very low primary-ion energies (below 100 eV).