Add to ORKGInternational audienceSiOx/SiO2 and SiOx/SiNx multilayers have been grown by reactive magnetron sputtering. Different fabrication parameters have been studied to optimize the density of Si nanoparticles (Si-nps) within the SiOx sublayer. The aim is to favor the optical properties of the film as well as the carrier transport for the future development of Si-np-based solar device. This chapter evidences the beneficial role of the SiNx sublayer on the achievement of good optical properties in a lower thermal budget with respect to the SiOx/SiO2 counterparts