Bulk focused ion beam fabrication with three-dimensional shape control of nanoelectromechanical systems

Although focused ion beam (FIB) milling has previously been used for fabrication of compliant nanostructures and devices, few instances of FIB nanomachining of such devices out of bulk materials have been reported. We use FIB to fabricate nanoelectromechanical systems (NEMS) devices out of bulk materials. Ion impingement from multiple directions allows sculpting with considerable three-dimensional control of device shape, including tapering and notching. Finite-element modeling of device frequencies agrees with optical interferometric measurements, including for the effect of a localized notch. We envision that bulk FIB fabrication will be useful for NEMS prototyping, milling of tough-to-machine materials and generalized nanostructure fabrication with three-dimensional shape control.