Fabrication of nano-gap electrodes and nano wires using an electrochemical and chemical etching technique

This paper reports a simple and controllable technique to fabricate nano-gap electrodes using a combined electrochemical and chemical etching. A line of metal is initially patterned using a conventional lithography process at the width of 2 µm. The line is then continuously etched until it is discontinued at the desirable gap. We have been successfully fabricated a <10 nm gap between two Au electrodes. Meanwhile for Cr electrodes a controllable gap of <5 nm has been achieved.