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

Abstract

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.