Accuracy of SIMS in determining ion implanted B doses as confirmed by nuclear reaction analysis

Abstract

The recent need for measuring depth profiles for ultralow energy B ion implants in Si has pushed the technique of secondary ion mass spectrometry (SIMS) into unprecedented degrees of high depth resolution. For such shallow implant distributions, it remained to be seen if the quantification procedures which have been used for determining deeper B in-depth distributions are accurate for these very shallow profiles. What is more, the B concentrations at the surface can be in the percent range for implants of 1E15/cm/sup 2/ at energies below 1 keV. It has not been demonstrated that SIMS can be accurate in this high-concentration regime. In this paper, we use the nuclear reaction /sup 11/B(p,/spl alpha/)/sup 8/Be to confirm the accuracy of the implanted doses in low-energy B implants in Si. Our results indicate that the doses measured by SIMS are within 5% of those measured using nuclear reaction analysis.