Embedded Nanostructures Revealed in Three Dimensions
I. Arslan,1*
T. J. V. Yates,1
N. D. Browning,2,3
P. A. Midgley1
Nanotechnology creates a new challenge for materials characterization
because device properties now depend on size and shape as much
as they depend on the traditional parameters of structure and
composition. Here we show that Z-contrast tomography in the
scanning transmission electron microscope has been developed
to determine the complete three-dimensional size and shape of
embedded structures with a resolution of approximately 1 cubic
nanometer. The results from a tin/silicon quantum dot system
show that the positions of the quantum dots and their size,
shape, structure, and formation mechanism can be determined
directly. These methods are applicable to any system, providing
a unique and versatile three-dimensional visualization tool.
2 Department of Chemical Engineering and Materials Science, University of California, One Shields Avenue, Davis, CA 95616, USA.
3 National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA.
* To whom correspondence should be addressed. E-mail: ia250{at}cam.ac.uk
