Fabrication of CoFe nanostructures by holographic lithography

A novel process that combines interference lithography and ion beam etching is presented for fabrication of magnetic submicron structures and nanostructures in this paper. Instead of an antireflective coating, vertical standing wave patterns were removed using oxygen descumming process. A series of magnetic submicronmeter structures were fabricated on Co0.9Fe0.1 films by this technique. Fabrication of magnetic nanostructures was performed by using a high exposure dose and modifications in optimized development conditions. A thin Au film was deposited on the sidewall of the magnetic nanostructures to avoid the oxidation of Co and Fe. The effect of this method was confirmed by X-ray photoelectron spectroscopy (XPS). Hysteresis loops measured by a highly sensitive superconducting quantum interference device (SQUID) technique show the different magnetic properties of the magnetic patterns with different critical dimensions.