A self-aligned nano-fabrication process for vertical NbN–MgO–NbN Josephson junctions. (22nd August 2017) - Grimm, A
Abstract: We present a new process for fabricating vertical NbN–MgO–NbN Josephson junctions using self-aligned silicon nitride spacers. It allows for a wide range of junction areas from 0.02 to several 100 μ m 2 . At the same time, it is suited for the implementation of complex microwave circuits with transmission line impedances ranging from < 1 Ω to > 1 k Ω . The constituent thin films and the finished junctions are characterized. The latter are shown to have high gap voltages ( > 4 mV ) and low sub-gap leakage currents.