Boron has been deposited successfully on Si(111) from the synchrotron‐radiation‐induced decomposition of decaborane (14), i.e., B10H14. The rate of deposition is limited by the adsorption rate of decaborane (14) on the surface. In addition there is some indication that there is an activation barrier to dissociative adsorption. The synchrotron‐radiation‐ induced growth rate of boron thin films from decaborane (14) is linear with coverage for a large range of thickness, suggesting a constant sticking coefficient for decaborane adsorption at room temperature.