A single‐grid ultra‐high‐vacuum‐compatible ion source was used to provide accelerated In+‐dopant beams during Si(100) growth by molecular‐beam epitaxy. Indium incorporation probabilities sgr;, determined by secondary ion mass spectrometry, in films grown atTs=800 °C were too low to be measured for thermal In (sgr;Inwas 550 °C) . However, for accelerated In+doping, sgr;In+at 800 °C ranged from 0.03 to ∼1 for In+acceleration energiesEIn+between 50 and 400 eV. Temperature‐dependent Hall‐effect and resistivity measurements were carried out on In+‐doped Si films grown atTs=800 °C withEIn+=200 eV . Indium was incorporated substitutionally into electrically active sites over a concentration ranging from 2×1015−2×1018cm−3, which extends well above reported equilibrium solid‐solubility limits. The acceptor‐level ionization energy was 156 meV, consistent with previously published results for In‐doped bulk Si. Room‐temperature hole mobilities mgr; were in good agreement with the best reported data for B‐doped bulk Si and were higher than previously reported values for annealed In‐implanted Si. Temperature‐dependent (77–400 K) mobilities mgr;(T) were well described by theoretical calculations, with no adjustable parameters, including lattice, ionized‐impurity, neutral‐impurity, and hole‐hole scattering. Lattice scattering was found to dominate, although ionized‐impurity scattering was still significant, at temperatures above ∼150 K where mgr; varied approximately asT−2.2. Neutral‐impurity scattering dominated at lower temperatures. Plan‐view and cross‐sectional transmission electron microscopy observations showed no indications of dislocations or other extended defects. Considering the entire set of results, there was no evidence of residual ion‐bombardment‐induced lattice damage.
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