Inelastic electron tunneling in aluminum-alumina-gold junctions exposed to thiocyanate ion: sensitive thiocyanate detection

Abstract

Inelastic electron tunneling spectra are reported for Al-Al 2 O 3 -Au junctions externally doped with KSCN from methanol solution. Spectra of the thiocyanate ion can be observed over a wide range of concentration, 10 -7 -10 -2 M. Because the tunneldiodes are completely fabricated prior to the doping process, and because the doping process is simple and only requires a few minutes, these devices may serve as solid-state chemical sensors. The spectra observed for externally doped junctions are essentially the same as those for junctions doped with KSCN during device fabrication