We seed a low-pressure radio-frequency plasma with micron and submicron silica particles and induce surface deposition of plasma-generated solid films. This process produces surface coatings ranging from few nm to several hundred nm. The size distribution of the coated particles (core plus shell) is monitored as a function of time and is found to increase both in mean size as well as in variance. To explain the broadening of the distribution we propose a deposition model which assumes that the reaction rate is nonuniform within the plasma. This model predicts that the average particle radius increases linearly with deposition time with a slope equal to the average deposition rate while the variance increases as a quadratic function of time. These predictions compare favorably with experiments conducted with seeds ranging 0.1-2.3 mum in radius. Based on this model we are able to obtain the distribution of film deposition rates in the plasma. We find that this distribution is wide with a substantial fraction of particles experiencing very low deposition rates. (C) 2003 American Vacuum Society.