An O2+ probe energy study for boron quantification in Si1−xGex (0 ≤ x ≤ 1) using secondary ion mass spectrometry

With SiGe device technology still developing, a concomitant effort to develop accurate dopant quantification over the entire Si1−xGex(0≤x≤1) range using ultra low energy secondary ion mass spectrometry is required. Here we present a comprehensive secondary ion mass spectrometry study of the B11+ yield behaviour from a range of Si1−xGex(0≤x≤1) reference samples implanted with the same B dose. Depth profiling conditions include near normal incidence O2+ over an energy range of 0.2−1.0keV. Quantification of the B concentration for each profile was achieved by determining the individual profile sensitivity factor. Only for EP≤300eVwas the variation in sensitivity factor with Ge well described by a linear dependence over the whole Si1−xGex(0≤x≤1) matrix.