The fabrication of composite material with embedded III-V quantum dots is of great interest due to promising silicon-based light emitting devices. In this work, the growth of self-assembled InAs quantum dots on Si substrates as well as subsequent capping layer formation by molecular beam epitaxy is presented. The evolution of size, density and shape of QDs are characterized by atomic-force microscopy. Bimodal size distribution of QDs at the submonolayer InAs coverage was observed. Full embedding into silicon matrix and dislocation free crystal structure of InAs QDs were confirmed by transmission electronic microscopy.