Contact detection for nanomanipulation in a scanning electron microscope.
Nanomanipulation systems require accurate knowledge of the end-effector position in all three spatial coordinates, XYZ, for reliable manipulation of nanostructures. Although the images acquired by a scanning electron microscope (SEM) provide high resolution XY information, the lack of depth information in the Z-direction makes 3D nanomanipulation time-consuming. Existing approaches for contact detection of end-effectors inside SEM typically utilize fragile touch sensors that are difficult to integrate into a nanomanipulation system. This paper presents a method for determining the contact between an end-effector and a target surface during nanomanipulation inside SEM, purely based on the processing of SEM images. A depth-from-focus method is used in the fast approach of the end-effector to the substrate, followed by fine contact detection. Experimental results demonstrate that the contact detection approach is capable of achieving an accuracy of 21.5 nm at 50,000× magnification while inducing little end-effector damage.
Automation College, Harbin Engineering University, Harbin 150001, China. rchhai@gmail.com
Changhai
C
Ru
Steve
S
To
D003198:Computer Simulation; D004583:Electrons; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*