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.