Protected Nanoelectrodes Of Two Different Metals With 30nm Gapwidth And Access Window

Reproducible fabrication of 30nm metallic nanogaps on silicon chips and their electrochemical characterization are presented. The fabrication of the chip is a combination of an optical lithography step and two electron-beam (e-beam) steps. An optimized adhesion layer/metal layer combination (Ti/Pt/Au) and an adopted two layer e-beam resist are used. Specifically the chip has been covered with different protection layers, access windows located on top of the nanogaps, calibration electrodes and contact pads, respectively. After characterization of the gaps and of the protection layer in 0.1M H"2SO"4 aqueous electrolyte, the deposition of Cu onto the nanogaps was demonstrated successfully.