  Scanning tunneling microscope lithography can be used to create
nanoelectronic devices in which dopant atoms are precisely positioned in a Si
lattice within $\sim$1 nm of a target position. This exquisite precision is
promising for realizing various quantum technologies. However, a potentially
impactful form of disorder is due to incorporation kinetics, in which the
number of P atoms that incorporate into a single lithographic window is
manifestly uncertain. We present experimental results indicating that the
likelihood of incorporating into an ideally written three-dimer single-donor
window is $63 \pm 10\%$ for room-temperature dosing, and corroborate these
results with a model for the incorporation kinetics. Nevertheless, further
analysis of this model suggests conditions that might raise the incorporation
rate to near-deterministic levels. We simulate bias spectroscopy on a chain of
comparable dimensions to the array in our yield study, indicating that such an
experiment may help confirm the inferred incorporation rate.
