Fabrication of focused ion beam-deposited nanowire probes for conductive atomic force microscopy

Probe development is crucial for advancing scanning probe microscopy (SPM) techniques. Among the various probe fabrication methods, one of the fastest and most accurate methods is focused ion beam-induced deposition (FIBID). This approach allows nanoscale prototyping of nanoobjects in a single maskless manufacturing step. The chemical composition of the deposited material, which forms the probe, is predefined by an applied precursor. Here, we present a method for tip fabrication using a Ga-focused ion beam (Ga-FIB) and a MeCpPtMe3 precursor. Nanowire tips were deposited on conventional SPM probes in the FIBID step. The materials were additionally shaped during the Ga-FIB milling process, annealed and purified in oxygen plasma. A tip radius equal to 30 +/- 5 nm was achieved. An analysis of their chemical composition was performed, including an indication of their suitability for conductive atomic force microscopy measurements. Finally, a series of current-voltage characteristics were recorded on highly orientated pyrolytic graphite.