Photoluminescence and Raman scattering experiments were performed on Si/SiO2 superlattices grown by radio frequency magnetron sputtering on Si, quartz and glass substrates. Increasing the Si layer thickness in the Si/SiO2 superlattice gave rise to an increased photoluminescence signal and a Raman signature for nanocrystalline Si. Annealing the superlattice at 1000 degreesC in nitrogen atmosphere also resulted in a significantly increased photoluminescence intensity that correlated with the formation of nanocrystalline Si in the Si/SiO2 superlattice. Relationships between the emergence of nanocrystalline Si and changes in the photoluminescence properties of Si/SiO2 superlattices are discussed. (C) 2001 American Institute of Physics.