PROPERTIES OF SI QUANTUM DOTS/SIOX POROUS FILM STRUC- TURES SYNTHESIZED USING THE HYDROFLUORIC TECHNOLOGY

A detailed study of Si quantum dots/SiOx film structures synthesized using a new hydrofluoric technology of forming silicon nanoparticles in porous silicon oxide matrices has been performed. A physical mechanism of the effect of chemical treatment in HF vapors in air on the structural and luminescent properties of the film porous systems with nanosized silicon has been suggested. We show that the passivation of the broken bonds on the surface of Si nanoinclusions as a result of the treatment occurs with the participation of oxygen, fluorine and hydrogen atoms, and this effect depletes the nonradiative recombination channel by two orders of magnitude. We suggest a model explaining the blue shift of the photoluminescence spectra as a result of the treatment due to a decrease in the sizes of the Si−QD during the oxidation of their surface layers.

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