Depth distributions and range parameters for He implanted in Si and GaAs

Depth distributions for He implanted in Si and GaAs measured by secondary ion mass spectrometry (SIMS) are reported as a function of ion energy from 20 to 300 keV at 1016 cm−2 fluence. The range parameters and Pearson IV moments are determined and tabulated. The ranges of 300‐keV He ions in both Si and GaAs are about 1.4 μm but the width of the profiles is greater for GaAs (σ=0.273 μm) than for Si (σ=0.140 μm). The profiles for all energies in both materials exhibit significant negative skewness (γ1≊−1.65). The SIMS detection limit for He is about 1018 cm−3 in both Si and GaAs. Implanted He depth distributions do not redistribute until an annealing temperature of 350 °C is reached.