Automated Four-Point Probe Measurement of Nanowires Inside a Scanning Electron Microscope

Nanomanipulation inside a scanning electron microscope (SEM) has been employed to maneuver and characterize nanomaterials. Despite recent efforts toward automated nanomanipulation, it is still largely conducted manually. In this paper, we demonstrate automated nanomanipulation inside an SEM for a well-structured nanomanipulation task via visual servo control and a vision-based contact-detection method using SEM as a vision sensor. Four-point probe measurement of individual nanowires is achieved automatically by controlling four nanomanipulators with SEM visual feedback. A feedforward controller is incorporated into the control system to improve response time. This technique represents an advance in nanomanipulation inside SEM and can be extended to other nanomanipulation tasks.