Synthesis of germanium nanoparticles in thin Si02 films

摘要

A method for synthesis of germanium nanoparticles 105 in thin Si02 films 104 comprising: preparing a solution comprising silicon esters, germanium tetrachloride (GeCl4) or germanium esters, methyl- or higher alcohols, and water; applying the solution to a surface of a substrate; consolidating the solution on the surface of the substrate, thereby obtaining a glass comprising silicon dioxide and germanium dioxide; selectively reducing the germanium dioxide to form germanium nanoparticles. The consolidation may be achieved by heating in an oxidising atmosphere to a temperature over 400 {C. The selective reduction may be achieved by heating in a reducing atmosphere of hydrogen mixed with an inert gas such as nitrogen at a temperature of between 800 and 1200 {C. The substrate may be silicon. The silicon ester may be tetraethoxysilane (TEOS). Also disclosed is a device comprising a substrate having a first layer of silicon dioxide and a second layer of silicon dioxide with germanium nanocrystals.