Improving the deposition rate for microcrystalline silicon (mu c-Si:H) prepared by Hot Wire Chemical Vapour Deposition (HWCVD) under the constraint of a low substrate temperature is the subject of this study. The influence of the deposition pressure and various combinations of filament configuration and filament temperature oil the deposition rate and material quality was investigated. Raman and infrared spectroscopy and solar cell J-V parameters are used to evaluate the quality of the material. Low deposition pressures and low filament temperatures at low filament-substrate distances are most suitable to obtain high quality material at improved deposition rates. Deposition rates of 4 angstrom/s were achieved for high quality material at a substrate temperature of 250 degrees C. (c) 2005 Elsevier B.V. All rights reserved.