Figure 8.

Density determination of FEBID/FIBID nanostructures. (a) Resonant vibration mode of single clamped pillars. The alternating excitation force can be applied via the pillar substrate through piezoactuators or via electrostatic forces surrounding the pillar. (b) Frequency sweeps of vibration amplitude (upper) and phase shift (lower) for a FEBID pillar across its fundamental vibration. The frequency inset shows the total 1 MHz scan and a single excitation, which is due to the uniformity of the deposited pillar. The SEM observation insets show the top view of the pillar in static and resonant mode. Modified from Friedli et al. [53]. (c) Mass measurement in the femtogram region via the frequency change of cantilevers during FEB or FIB deposition. The inset shows the shift in frequency during an FEBID deposition. Modified from Friedli et al. [46].