In low‐temperature (300–350 °C) silicon epitaxy employing low‐energy inert‐gas ion bombardment on a growing film surface, the effects of ion bombardment energy and ion flux as well as that of ion species on the crystallinity of a grown silicon film have been experimentally investigated. It is shown that the energy dose determined by the product of ion energy and ion flux is a main factor for epitaxy that compensates for the reduction in the substrate temperature. Large‐mass, large‐radius ion bombardment using Xe has been demonstrated to be more effective in promoting epitaxy at low substrate temperatures than Ar ion bombardment. Thus, low‐energy, high‐flux, large‐mass ion bombardment is the direction to pursue for further reducing the processing temperature while preserving high crystallinity of grown films. ©1996 American Institute of Physics.