While searching the internet for “nanotechnology,” I was
not surprised to find many definitions. Two of these are as follows:
(1) nanotechnology is the development and use of devices that have a
size of only a few nanometers; and (2) nanotechnology can best be
considered as a “catch-all” description of activities at
the level of atoms and molecules that have applications in the real
world. While nanotechnology is usually focused on the building
of structures at the atomic scale, the characterization of
such structures should also be considered as nanotechnology. At the
Microscopy and Microanalysis 2002 Meeting in Quebec City, together with
Tom Kelly and Mike Thompson, I organized a symposium entitled
“Advances in Nanoscale Technology.” The response to this
symposium was impressive, with 32 contributed and 7 invited
presentations. Some of these presentations concentrated on atom probe
field ion microscopy and form the basis for the invited contributions
in this special issue of Microscopy and Microanalysis.
The atom probe field ion microscope was developed over 35 years ago
at the Pennsylvania State University by Prof. E.W. Müller and
coworkers. Almost 20 years later, the three-dimensional atom probe
(3DAP) was developed, which allowed the position and chemical identity
of the majority of individual atoms in a small volume of material
(typically ∼30 nm by ∼30 nm by ∼100 nm) to be mapped (for
further details see Atom Probe Field Ion Microscopy, M.K.
Miller et al., Oxford University Press, 1996). In the past 15 years,
the 3DAP technique has been advanced (in both instrumentation
development and materials science applications) by various research
groups around the world, including those at the Université de
Rouen (France), the National Institute for Materials Science (Japan),
the University of Oxford (UK), Chalmers University of Technology
(Sweden), Northwestern University (USA), and the Oak Ridge National
Laboratory (USA). The 3DAP has been applied to a wide variety of
materials science studies including phase transformations,
precipitation, segregation, and atomic clustering. This issue provides
a sampling of the recent contributions of the 3DAP technique to the
characterization of nanoscale structures in different materials systems
including steels, superalloys, aluminum-based alloys, and multilayer
magnetic thin films. There are also papers on the advancement of
instrumentation and data manipulation techniques.
As nanotechnology continues to advance, so must the characterization
techniques used to tell the “builders” what they have
fabricated. It is the responsibility of the microscopy community to
develop and implement the techniques that make this feedback possible.
It is fortuitous that the characteristic length of structures
characterized in the 3DAP and those fabricated in nanotechnology are
similar. Due to its capability to characterize small structures atom by
atom, the 3DAP is a powerful tool able to assist and accelerate the
advances currently taking place in nanotechnology. I hope this issue
provides the reader with a useful overview of the application of atom
probe field ion microscopy to the nanoscale analysis of materials and
that these papers stimulate future applications.
