Automatic nanohandling station inside a scanning electron microscope

Abstract

Current research work on the development of automated nanohandling systems in a scanning electron microscope (SEM) is presented. Two experimental set-ups are shown in which nanohandling robots operate in the vacuum chamber of an SEM. A client—server control system that can integrate various microrobots and sensors has been developed and evaluated by automatic handling of TEM (transmission electron microscope) lamellae by two nanorobots. The robots are controlled in a closed-loop way by using images from several CCD (charge coupled device) cameras and from the SEM. Algorithms for real-time processing of noisy SEM images have been implemented and tested. The experiment on automatic handling of TEM lamellae inside an SEM is described. The other set-up contains a nanohandling robot using the probe of an atomic force microscope (AFM) as end-effector. The manipulation of individual multiwall carbon nanotubes (MWNTs) and the characterization of nanofilms by nanoindentation are the applications being investigated. The experimental set-up includes a nanopositioning piezo stage with three degrees of freedom (DoF) and a three-axis nanomanipulator. Piezoresistive AFM probes are applied as end-effectors. In this way the acting forces can be detected, allowing force feedback for the station's control system. First investigations have been carried out by bending MWNTs and calculating their elastic modulus.