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SIMS backside depth profiling of ultrashallow implants using silicon‐on‐insulator substrates

We report the use of secondary ion mass spectrometry (SIMS) backside depth profiling for ultrashallow implants using silicon‐on‐insulator (SOI) wafers for substrate thinning. The SOI layer, after removal of the buried oxide layer, provides a smooth and flat surface for high‐resolution SIMS depth profiling from the backside. The dopant distribution of 0.5 keV boron implants (5 × 1014 atoms cm−2) was studied by performing both front and backside depth profiling using 0.5–5 keV O2+ primary ions at oblique incidence in a Cameca IMS‐6f SIMS instrument, with and without sample rotation. The backside depth profiles give significant improvement in depth resolution compared with conventional frontside SIMS depth profiling. Copyright © 2002 John Wiley & Sons, Ltd.