Electroless silver deposition on the nanometre scale: Limits and opportunities

A new, simple, inexpensive and eco-friendly method allows selective yet uniform silver metallizing of silicon structures up to 10 nm thick, and with aspect ratios in excess of 4. The electroless deposition takes place from a supersaturated aqueous silver solution with hydroxide ions at pH 11 which causes nucleation to occur on the surface. The deposition process occurs best on small structures, and it is seen that the nucleation process is critical in formation of the silver deposit. Qualitative measurements show that electrical conductivity is established between silver and the underlying silicon wafer.