Particle formation processes in silane plasma have been studied by means of ab initio molecular orbital method and the Derjaguin–Landau–Verway–Overbeek (DLVO) theory. The results from a quantitative comparison between the Si–H bonding energy of negative species and that of neutral ones suggested the presence of the polymerization pathways via negative species. The DLVO theory has been applied to calculate the interaction potential energy between the charged particles. It was found that the heterogeneous aggregation accelerates the particle growth. © 1998 American Institute of Physics.