Quantitative SIMS analysis of nitrogen using in situ internal implantation

The peak concentration of nitrogen implanted into a silicon wafer was determined by the in situ internal standard implantation of 14Nq followed by the SIMS depth profiling analysis of 30Si14Ny. Quantification was done as follows. As an internal standard, the N ions with a known fluence were directly implanted into the sample using a SIMS instrument. The depth profile of 30Si14Ny was then measured. The standard deviation of the projected range in the depth distribution, DRP, and the ion intensity for each peak was carefully measured. The actual concentration of nitrogen for the internal implant was calculated from its measured DRP value and the fluence. The nitrogen concentration for the original implant was then evaluated by comparing the ion intensity ratio of the internal implant peak to the original implant peak with their concentration ratio. The concentration thus estimated was in good agreement with the actual concentration. The DRP values measured from the depth profiles were also compared to the theoretical ones. q1999 Elsevier Science B.V. All rights reserved.