ИСТИНА

In this work we would like to demonstrate a simple technique that allows to produce nanogaps (<5 nm) between gold electrodes using nothing else standard nanolithography procedures. The method is based on ion etching of gold film through a polymer mask formed by the electron-beam lithography. An argon plasma was used for the ion etching. A low molecular weight polystyrene was used as a negative tone resist. The substrate with 20 nm gold film was coated by 25 nm polystyrene using vacuum thermal sputtering as described in [6]. This deposition method allows making thin resist layer and varying a resist thickness by a very simple way to fine tune the process. The electron-beam lithography patterns contained 20 nm wide lines with 30 – 10 nm separation between them. After the ion etching through the resist mask the size of the obtained gaps between metal electrodes can be even smaller due to isotropic component of etching and proximity effect during patterning. We demonstrate that small nanogaps (<5 nm) can be obtained by such simple method with a relatively high yield. Also it was shown that this method is good for making many-electrode systems with a nanometer scale separation leading contact to a small area on the surface of a substrate. The main advantages and limitations of the method are discussed.