Gold Electrodeposition into Mesoporous Silicon: The Effect of Solution Composition

Electrodeposition of Au in mesoporous Si prepared in a highly doped p-type Si was investigated. When the Au electrodeposition was carried out using the complex Au(S2O3)(2)(3-), the mesopores with 5 mu m depth were filled with Au continuously from the bottom to the opening. When the Au electrodeposition was carried out using the complex AuCl4-, the openings of the mesopores were covered with an Au film. The solution composition has a strong influence on the electrodeposition behavior. The effect of the displacement deposition occurring at the initial few seconds before conducting the Au electrodeposition seems to be a key factor for the difference. The different behaviors of the electrodeposition with different supporting electrolytes were compared and discussed.