The fluidized bed Chemical Vapor Deposition (CVD) process constitutes today one of the most efficient techniques to modify the surface properties of dense (nonporous) powders. The success encountered in this field is the reason why this process has been extended to the treatment of microporous powders, for which there are very important industrial interests. The article presents an experimental analysis of the influence of the main operating parameters on the spatial localisation. and the nanostructure of silicon deposits from silane on microporous powders. The first results obtained show that uniform deposits appear on all the surfaces of the pores in the form of discontinuous rafts. These results, which will be coupled with a theoretical predictive model, prove that the control at the nanometric scale of the organization of CVD materials on microporous powders today has become possible.