Electrochemical deposition of Te and electroless deposition of Se nanoparticles in etched tracks of Au+ ions in SiO2 layer on n-Si(1 0 0) wafers

The techniques for Te electrodeposition and Se electroless deposition into nanoporous SiO2 layer on n-Si(1 0 0) substrate are developed. To produce a porous SiO2 layer, scanned beams of 400 MeV Au+ ions are employed for the bombardment of silicon oxide thermally grown on Si(1 0 0) substrate. Pores are formed by chemical etching of the irradiated SiO2 layer in dilute HF. Etching results in the formation of the uniform pores randomly distributed over the surface and shaped like truncated cones with base diameters of 100 and 250 nm. Electrodeposition of Te into nanopores of SiO2 layer takes place at potentials below the silicon flat band potential. Te electrodeposited selectively into the nanopores – deposition on insulating SiO2 layer – is excluded. Electrodeposition of Se into nanopores takes no place due to Se reduction to H2Se. Chemical interaction of H2Se and H2SeO3 in the solution leads to the formation of roundish Se particles on SiO2 surface near the pores. Precipitation of Se into nanopores is realized by electroless deposition from SeO2 solution with addition of HF.