Precursor competition in focused-ion-beam-induced co-deposition from W(CO)6 and C10H8

Abstract

Focused-Ion-Beam-Induced Deposition (FIBID) is a direct-write lithography process aiming to produce functional deposits from a precursor gas and widely used in nanotechnology. Current developments in FIBID envision the use of two precursors simultaneously in order to produce binary compounds, enhancing the searched functionality. In the present work, we explore Focused-Ion-Beam-Induced co-deposition from simultaneous flux of W(CO)6 and C10H8 precursors. Contrary to expectations, we obtain inhomogeneous co-deposits, where areas of high W concentration and low C concentration segregate from areas with low W concentration and high C concentration, on top of significant sputtering effects due to the reduced growth rate. A subtle competition between the two precursor gases used plus the sputtering effect produced by Ga-ions are invoked to explain the obtained results. Our results highlight the potential of co-deposits using FIBID but underline the necessity of a better understanding of precursor competition to further development of this approach.