SCANNING ELECTRON MICROSCOPY BASED MANIPULATION
AND CHARACTERISATION OF NANO-SCALE OBJECTS
St. Fahlbusch
1
, S. Hoffmann
1
, I. Utke
1
, A. Steinecker
2
, J.-M. Breguet
3
and J. Michler
1
1
Empa, Materials Science and Technology
Laboratory of Materials Technology
Feuerwerkerstrasse 39,CH-3602 Thun, Switzerland
2
Centre Suisse d'Electronique et de Microtechnique SA
Untere Gruendlistrasse 1, CH-6055 Alpnach Dorf, Switzerland
3
Swiss Federal Institute of Technology Lausanne
Laboratoire de Systèmes Robotiques
CH-1015 Lausanne, Switzerland
Abstract: Two scanning electron microscopy (SEM) based devices for positioning,
manipulation and imaging at the nano-scale have been developed. The control and
vision system is based on both a commercial scanning probe microscopy (SPM)
controller and a client-server approach to ensure that nanopositioning and SEM
image processing are executed in real-time. The evaluation of the two devices has
been performed by implementing three different applications: (i) attachment of
carbon nanotubes on SPM tips, (ii) investigation of mechanical properties of
nanowires and (iii) tensile strength measurements for focused electron beam
deposits. Copyright © 2006 IFAC
Keywords: Cartesian manipulators, image processing, manipulation tasks,
mechanical properties, robot control, robotic manipulators, telemanipulation.
1. INTRODUCTION
In recent years, the manipulation and characterisation
of nanowires (NWs) and carbon nanotubes (CNTs)
became a matter of particular interest in research.
Due to their unique structure, small size, high aspect
ratio and low density as well as excellent mechanical
and electrical properties, nanotubes are expected to
find use in a wide range of applications. Mounted on
tungsten tips they can be applied as field emitters in
displays or in high-resolution electron beam
instruments (Bonard, et al., 1998; De Jonge, et al.,
2003). CNTs mounted on atomic force microscopy
(AFM) tips promise to overcome the limitations of
standard tips regarding resolution and wear (Stevens,
et al., 2000). Nanowires are of interdisciplinary
interest to applications in the fields of bio-medical
sensing, nano- and optoelectronics and photovoltaics
due to their electrical, optical, mechanical and
geometrical properties that deviate quite substantially
from bulk (Law, et al., 2004).
For all these applications dedicated tools are
essential to functionalise, manipulate and
characterise – both mechanically and electrically –
CNTs and NWs and assemble them into nano-
devices. In addition, novel processes and strategies
for nano-scale visualisation have to developed based
on high spatial resolution imaging instruments like
scanning electron microscopes (SEMs).
The manipulation and characterisation of nano-scale
objects and of matter even at the atomic level has
been opened up by the invention of the scanning
tunneling microscope by Binning and Rohrer in the
early eighties, and the subsequent invention of the
atomic force microscope by Binning, et al. (1986).
Scanning probe microscopy (SPM) based
nanomanipulation has rapidly gained in importance
during the last ten years, and several kinds of
manipulation systems have been developed
(Schaefer, et al., 1995; Requicha, et al., 1998; Theil-
Hansenyk, et al., 1998; Li, et al., 2003). To
overcome the main drawback of these systems, i.e.
the lack of visual feedback in real-time, SPMs have
been combined with haptic devices
(NanoManipulator, NanoFeel, Omega Haptic
Device), and virtual reality interfaces have been
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