Fabrication of nano-gap electrodes using electroplating technique

We report a simple and controllable method for fabricating a pair of electrodes with a sub-10-nm gap, namely nano-gap electrodes, by using a conventional electroplating technique. A pair of initial electrodes with a 100–200 nm gap is fabricated by electron beam lithography, and then gold is deposited electrochemically to reduce this gap. A sub-10-nm gap is produced by halting the electroplating just before the electrodes make contact with each other. We also use our technique to fabricate nano-gap electrodes with a gold and a platinum finger, and with three gold fingers.