Silicon epitaxial films have been deposited on 51-nm phi Si substrates by the molecular beam technique. Silicon and the dopant antimony are evaporated from separate sources. Typical process conditions before and during the growth are as follows: substrate heat cleaning at 1173K for five minutes, substrate temperature 1023 K, growth rate 1 mu m/h, film thickness between 0. 1 and 3 mu m. This procedure is found to produce dislocation-free films. The total Sb concentration in the MBE films has been measured by neutron activation analysis, the electrically effective concentration with Hall or C-V measurement. Carrier concentrations between 3 multiplied by 10**1**4 and 2 multiplied by 10**1**9 cm** minus **3, and Hall mobilities between 100 and 1400 cm**2/Vs have been obtained.