contact person: Alan Kubis (email@example.com)
Visualization of the three-dimensional relationship of
structures in materials has become an important tool in the materials
science community. As structures have become smaller in the semiconductor
industry, and the field of nanotechnology has emerged it is increasingly
important to be able to reconstruct features at the sum-micron level. Our
group uses the FIB to obtain serial sections of materials with tens of
nanometer resolution allowing the visualization and interrogation of
nanoscale structures. By using the in situ milling capability of the FIB and
its high resolution imaging power three-dimensional reconstructions can be
produced using various computer algorithms and visualization packages.
Several systems have been investigated using this technique.
Using the imaging and ion mapping capabilities of the FIB in our facility
electronic via structures were looked at to show the techniques ability to
correlate structural features with their elemental constituents. Below the
Secondary electron reconstruction can be compared with the Aluminum,
Titanium and Oxygen reconstructions clearly delineating the Al fill, TiN
diffusion layer and SiO2 dielectric layer.
Comparison of Secondary Electron reconstructions with
three different elemental reconstructions
D.N. Dunn, R.
Hull, Appl. Phys. Lett. Reconstruction of three-dimensional chemistry and
geometry using focused ion beam microscopy, 75(21) 3414-3416 (1999).
An aluminum grain structure was also reconstructed to show
the applicability to metallurgical systems. In both cases, a fairly simple
reconstruction was used to create these structures. A more complex algorithm
was written, based on techniques used in the Medical imaging field, using a
shape based interpolation (SBI) method. This method allows much more complex
morphologies to be studied and more accurately reconstructs features at the
nanoscale level. In conjunction with Gary Shiflet’s group (UVa, Dept. of
Materials Science) a Cu-15In colony was reconstructed using the SBI method.
The highly complex morphology of these colonies can be clearly observed and
in the case of c) the elemental distribution of Indium in the colony can be
D.N. Dunn, G.J. Shiflet, R. Hull, Quantitative
three-dimensional reconstruction of geometrically complex structures with
nanoscale resolution, Rev. Sci. Instru. 73(2) 330-334 (2002).
To more clearly observe the morphology in these complex
structures cross sections of the volumes can be put into animations so that
the full structure can be observed. Below is a three-dimensional
reconstruction of a Nickel-Based Superalloy used in jet aircraft engines.
The gamma prime phase is shown with the gamma phase removed. By clicking on
the image below layers will be removed allowing the whole structure to be
Nickel-Based Superalloy provided by D. Backman, GE
We are currently working to increase the resolution of this
technique to study Self-assembled quantum dot structures in support of the
MRSEC Center for Nanoscopic Research. Other materials, such as devitrified
aluminum glasses, are being investigated in conjunction with Gary Shiflet’s