Abstract: An improved hot filament chemical vapor deposition (HFCVD) reactor is disclosed comprising a gas dispersion system, a filament network and an apertured support plate for the substrate. The apertures in the support plate provide for counteracting the natural pressure and temperature gradients which arise within the reactor so that a uniform deposit or material can be coated over the entire surface of multiple small pieces simultaneously. Specifically, the apertured support plate substantially reduces the extent of radial (stagnation point) gas flow adjacent to the substrate which significantly improves coating uniformity.