The growth of polycrystalline silicon (polysilicon) films from SiF4/SiH4/H-2 gas mixtures is reported. The polysilicon films have been deposited in a multi process reactor by a PECVD process. The effect of r.f. power, chamber temperature and gas flow ratios on grain size and deposition rate have been determined. The fluorine concentration and the grain sizes of the films have been determined by SIMS and atomic force microscopy (AFM), respectively. Grain sizes in excess of 900 Angstrom are reported for layers deposited at 300 degrees C.