ON THE XPS PEAK SHAPE-ANALYSIS

Inelastic background or the peak shape parameter is defined as the rat io of the area under the primary photoelectron peak to the height of t he accompanying inelastic loss background measured at 30 eV below the peak energy. This parameter has been experimentally determined for hom ogeneous polycrystalline samples of Au, Ag and Cu. Inhomogeneous speci mens prepared by depositing graphite overlayers on Au films are also i nvestigated. The effect of the choice of background level on this para meter is determined. A simple experimental test is proposed to determi ne the validity of the existing first-order analytic expressions for t his parameter. Angle-resolved studies are performed to explore the pos sibility of contribution arising out of surface excitations.