Glove-box-based fabrication system for inelastic electron tunneling junctions

Abstract

The design and the utility of a glove-box-based fabrication system for inelastic electron tunneling junctions are described. The system consists of a stainless-steel, turbomolecularly pumped ultrahigh-vacuum fabrication system, mounted to the evacuable entrance chamber (vacuum box) of the glove box. The glove box is a recirculating, catalytically purified, argon-based system, with a reactive impurity concentration below 2 ppm. In particular, there is ≲1-ppm water vapor. To demonstrate the advantages of the system, junctions prepared with m-cresol (3-methylphenol) chemisorbed from both the vapor and the liquid phases are compared, as well as junctions prepared with ethanolamine (2-aminoethanol) chemisorbed from the liquid phase both inside the glove box and externally in the laboratory atmosphere. Junctions prepared from the liquid phase with m-cresol exhibit significantly greater intensities (higher surface concentration) compared to the vapor-phase adsorption. The junctions prepared with ethanolamine exhibit spectral changes characteristic of different surface structures depending upon whether the adsorption is done in an inert atmosphere or in the laboratory atmosphere.