Localized Nucleation and Growth of Pb clusters on n-Si(111):H surfaces

摘要

Metal clusters with widths of a few nanometers have been electrochemically deposited onto foreign metal substrates by several groups using scanning probe microscope(SPM)techniques [1-5].However,in view of electronic applications,metal nanostructures are required to be deposited onto semiconducting or isolating substrates.The major problem,which arises during electrochemical nanostructuring of semiconducting,e.g.silicon,surfaces is to image the deposited metal nanostructure.A potential difference of several hundred mV between tip and substrate,which is necessary for imaging silicon surfaces with STM in an electrochemical enviroment,and usually applied tunneling currents in the range of 0.5-2 nA result in a dissolution of previously deposited metal [6],Nevertheless,very few groups have achieved a local deposition of metal clusters on silicon surfaces [7,8].