The Sb incorporation probability in homoepitaxial Si(001) films grown by ultrahigh vacuum ion‐beam sputter deposition at temperaturesTsbetween 100 and 300 °C was found, using quantitative secondary ion mass spectrometry, to be unity with no evidence of surface segregation. Surface roughnesses and epitaxial thicknessestewere measured by atomic force microscopy and cross‐sectional transmission electron microscopy, respectively, for both undoped and Sb‐doped Si layers. Sb doping was found to dramatically increase the rate of surface roughening and to decreaseteby a factor of ≳2 at growth temperatures between 250 and 300 °C while having no measurable effect at lower temperatures. ©1995 American Institute of Physics.