Arsenic doping of epitaxial grown Si over the temperature range from 850°C to 550°C was investigated in an ultraclean atmospheric-pressure chemical vapor deposition reactor. Growth was carried out from dichlorosilane (DCS) in H2 carrier gas. Arsenic could be incorporated into single crystal silicon at levels approaching 10 at. %. Carrier concentrations exceeding 1×1020/cm3 were obtained for the as-grown films. The material remained single-crystalline, as measured by ion channeling and cross-section transmission electron microscopy, and exhibited excellent surface morphology with no Hillock formation observed. AsH3 dramatically enhanced the growth rate of Si at lower temperatures.