Sputtering transients for some transition elements during high-fluence MEVVA implantation of Si

The approach to quasi equilibrium sputtering of transition elements Co, Er. V and Ni during high-fluence implantation of Si(1 1 1) using a metal vapou r vacuum are (MEVVA) source has been studied by time of flight-energy elast ic recoil detection analysis (ToF-E ERDA) and scanning electron microscopy (SEM). The partial sputter yield of the implanted species was determined fr om the change in the content of the implanted species with the implanted io n fluence. The partial sputter yield of Co exhibits a step-like rise to sim ilar to0.4 that might be associated with a rapid segregation of Co to the s urface followed by a slow exponential-like increase. Er on the other hand f ollows an exponential approach to the quasi-equilibrium partial sputtering yield which is indicative of no strong buildup of Er within the sputter esc ape depth. Additional data for Ni and V suggest also an exponential approac h to quasi-equilibrium sputtering. (C) 2001 Elsevier Science B.V. All right s reserved.