INJECTION OF SELF-INTERSTITIALS DURING SPUTTER DEPTH PROFILING OF SI AT ROOM-TEMPERATURE

Samples consisting of multi B delta layers and a single Sb delta layer , grown using molecular beam epitaxy, have been sputter depth profiled using O-2(+) ions with incidence energy of 8.2 or 3.2 keV. The leadin g and the trailing edge of the B distributions show an anomalous broad ening induced by the sputtering, which apparently increases with ion e nergy. Similar feature is not observed for the Sb distribution. Incorp oration of substitutional C to concentrations similar to 10(19) cm(-3) suppresses the broadening feature almost completely. This anomalous b roadening is interpreted as a consequence of injection of Si self-inte rstitials from the region damaged by the ion bombardment. These inters titials may migrate far beyond the mixing depth and interact with the B dopants, which yields a mixing of the B atoms before the distributio n is within the ''ordinary'' mixing depth. (C) 1998 American Institute of Physics. [S0003-6951(98)03147-7].