Top-down meets bottom-up — Electron-beam induced metalorganic deposition of amorphous iron oxide nanostructures

We present the use of a metalorganic precursor, iron(III) 2-ethylhexanoate, as a precursor for the electron-beam induced deposition of amorphous iron oxide nanostructures. Exposing this precursor to an area dose of 1.560 mC/cm2 with 10 keV electrons affords a material that can be developed and was determined to be amorphous iron oxide when examined by TEM, electron diffraction, and energy dispersive X-ray spectroscopy. Single point exposure yields free-standing hollow nanorods with diameters from 85 to 255 nm controlled by the exposure dose. The patterning of sub 40 nm nanowires with low (<3 nm) line edge and width roughnesses is also presented.Key words: electron beam lithography, amorphous iron oxide, nanotubes, nanowires, coordination polymer precursor.