On the anomalous SIMS transient of B in Si: the influence of surface conditions

Abstract

The SIMS 11B+ signal from a homogeneously boron-doped silicon sample was measured with a 1 keV O2+ beam at 60° incidence without oxygen flooding. Stationary levels of boron secondary ions were reached only at a depth of ∼40 nm. In vacuo rotation of the analysed samples during interruption of the profiling revealed that there is no relation between the anomalous long boron transient and the formation of surface ripples by the ion beam. In contrast, removal of the native oxide by HF prior to the SIMS analysis resulted in a reduction of the boron transient to a normal value of ∼6 nm. This work shows that for accurate dynamic SIMS analysis the initial surface condition can be important. Copyright © 2001 John Wiley & Sons, Ltd.