A novel method to determine the ion sputter coefficient of dilute segregating impurities

A combination of linear programmed heating (LPH) and 3 keV Ar+- ion sputter ing was used to obtain Sn sputter coefficients at room and elevated tempera tures using a novel new method. At room temperature the determined value ag rees well with the elemental sputter yield, Y-sn = 2.5, if sputter yield am plification (SYA) of a submonolayer thin Sn film on a Cu(111) surface is ta ken into account. However, at high temperature the sputter coefficient decr eases to 1.1. This decrease can be explained if it is assumed that not all Sn atoms are removed from the surface into the vacuum by the sputtering pro cess, but knocked on into the bulk of the Cu matrix. At elevated temperatur es these Sn atoms segregate back to the surface and can be sputtered once a gain. (C) 2001 Elsevier Science B.V. All rights reserved.