Nanolithography with an atomic force microscope for integrated fabrication of quantum electronic devices

Abstract

We describe a novel technique using an atomic force microscope (AFM) for integrated nanometer‐scale lithography on various mask materials such as photoresist or gold covering a mesa‐etched GaAs‐AlGaAs heterostructure at ambient conditions. The generated patterns can be transferred to the two‐dimensional electron gas by wet chemical etching or by ion beam irradiation. We succeed in fabricating hole arrays with a periodicity down to 35 nm and a hole diameter of only a few nanometers. In magnetoresistance studies on so‐called antidot devices with 95 nm period at T=4.2 K we can clearly observe commensurability oscillations, demonstrating the successful pattern transfer to the electron system. With the AFM we can also pattern lines of varying width and depth into prefabricated devices.