Sandwich-type gated mechanical break junctions

Abstract

We introduce a new device architecture for the independent mechanical and electrostatictuning of nanoscale charge transport. In contrast to previous gated mechanicalbreak junctions with suspended source–drain electrodes, the devices presentedhere prevent an electromechanical tuning of the electrode gap by the gate. Thissignificant improvement originates from a direct deposition of the source and the drainelectrodes on the gate dielectric. The plasma-enhanced native oxide on the aluminumgate electrode enables measurements at gate voltages up to 1.8 V at cryogenictemperatures. Throughout the bending-controlled tuning of the source–drain distance, theelectrical continuity of the gate electrode is maintained. A nanoscale island in theCoulomb blockade regime serves as a first experimental test system for the devices, inwhich the mechanical and electrical control of charge transport is demonstrated.