In this work, the organic residue and oxide on silicon wafer were treated with UV-excited oxygen and trifluoronitrogen gases as a pro-treatment for silicon homoepitaxy. A typical positive photo resist, AZ 1512, was coated as a model organic residue. UV-O-2 cleaning (UVOC) and UV-NF3/H-2 treatment removed the organic residue and native oxide layer, respectively, for silicon epitaxial growth. A study of removal rate showed that the processing temperature is a more critical process parameter than pressure. Besides, hydrogen dilution improves the surface roughness of UV-NF3-treated surface as shown in the atomic force microscope images. (C) 2002 Published by Elsevier Science B.V.