Characterization of a hybrid nanowire-MEMS force sensor using direct actuation

In this study, we describe a process of characterization of a 3-axial force sensor with piezoresistive silicon nanowires. We present a unique method for determining the gauge factor (GF) of a volumetric structure with a stiffness exceeding 10⁵N m⁻¹ and resonant frequencies above 10 MHz. We employed an uncommon Lab-in-Scanning Electron Microscope (Lab-in-SEM, LIS) approach to perform a full characterization schedule under vacuum conditions using direct actuation with nanomanipulators. We discuss the force evaluation errors arising from the sample support stiffness. Finally, we present the results of GF measurements of the multi-axially investigated device with GF of over 20 for axial and over 40 for transverse loading.