Application of extra‐low impact energy SIMS and data reduction algorithm to USJ profiling

Secondary ion mass spectrometry analysis of ultra-shallow (sub-200 eV) B implants is complicated by the presence of native oxide on the surface of Si. Knowledge of the type of oxide present on the surface as well as accurate oxide thickness is very important for correct data reduction in extra-low energy depth profiling. Sputter rate (SR) variation approach based on the accurate SR measurement in Si and SiO2 can be successfully applied to B implants done through thermal oxides of various thicknesses. Lowest profiling energy should be used to achieve the least profile distortion in the case of de-channeled B implants: the rule of half of the implant energy used for profiling energy is confirmed. Profiling energy that is equal to the implant energy can be used if implantation is done through native oxide or into the stripped Si. If no thermal oxide is present on the surface, the most consistent result will be obtained when implants are done into the pre-stripped Si thus eliminating uncontrollable and variable native oxide-related issues. Copyright © 2012 John Wiley & Sons, Ltd.