A beneficial application of backside SIMS for the depth profiling characterization of implanted silicon

Abstract

AbstractAfter ion implantation, annealing is needed to activate dopant and recover crystalline. However, in some annealing conditions there is a possibility that activation annealing forms defects in the implanted region, which may cause errors in SIMS depth profiles. The purpose of this study is to make clear the influence of defects generated during annealing on the conventional front‐side SIMS (FSS) depth profiles, and to provide proper measurement condition to get accurate depth profiles using back‐side SIMS (BSS) technique as another beneficial application. In this study, BF2 were implanted into crystalline silicon, and three different samples were treated, respectively, as implanted, 750 and 900° annealing. In an as‐implanted sample, BSS depth profiles of boron confirmed those obtained by FSS. On the other hand, in annealed samples, BSS depth profiles were steeper than those of FSS. This result suggests that the degradation of depth resolution in FSS cannot be explained only by the effect of ion mixing due to primary ions, but may be related with the crystalline structure in the implanted region. Therefore, BSS techniques can also be indispensable for getting more precise depth profiles in the implanted region of silicon. Copyright © 2010 John Wiley & Sons, Ltd.