Temperature Dependent Broadening Effects in Oxygen SIMS Depth Profiling

In sputter depth profiling, the ultimate depth resolution is limited by ion bombardment-induced broadening effects [1]. The combined effect of atomic mixing and selective sputtering was recently shown to be responsible for the usually observed exponential tail in SIMS sputter depth profiling [2,3]. Segregation induced by surface oxidation was suggested to explain the unusually long tails observed for Ag [4] and other elements [5] in Si using Ar primary ions and in-situ oxygen flooding. Recently, radiation enhanced diffusion was substantiated by SIMS profiling with Ar primary ions at elevated temperature in the systems Mo/Si [6] and Ni/Cu, In/Cu [7]. In this study, we investigated the broadening of SIMS depth profiles of the dopants As and Ga implanted into Si using O2 primary ions and varying the sample temperature. The main purpose was to obtain more information concerning the role of oxidation-induced impurity segregation in sputtering with oxygen ions.