Langmuir, Vol.25, No.16, 9473-9479, 2009
Gold Removal from Germanium Nanowires
We report the selective removal of gold from the tips of germanium nanowires (GeNWs) grown by chemical vapor deposition on gold nanoparticles (AuNPs). Selective removal was accomplished by aqueous hydrochloric acid solutions containing either potassium triiodide or iodine, Measurement of the residual number of gold atoms on the GeNW samples using inductively Coupled plasma-mass spectrometry shows that 99% of the gold was removed. Photoemission spectroscopy shows that the germanium Surfaces of these samples were not further oxidized after treatment with these liquid etchants. Auger electron spectroscopy shows that AuNPs that did not yield GeNWs contain germanium and also that the addition of gaseous HCl to GeH4 during GeNW growth increased the selectivity, of germanium deposition to the AuNPs.