Phosphorus doping of ultra-small silicon nanocrystals

P-doped Si nanocrystals (radius <= 2 nm) were synthesized by depositing an ultrathin (0.3 nm) P-SiO2 film close to each SiO layer of SiO/SiO2 multilayers. During annealing P atoms migrate into the Si-rich region. Due to the low diffusivity of P in SiO2, P atoms segregate in the Si nanocrystal region and are incorporated in the silicon nanostructures. The P level in the Si nanoclusters can be controlled by changing the P content in the P-SiO2 layer.