The National Institute of Standards and Technology (NIST) will soon release a series of single-walled carbon nanotube
(SWCNT) reference materials (RMs) to provide users with a well-characterized material for their applications. The
SWCNT reference material will be introduced as a series of three types of material: (1) raw soot characterized for
composition, which will be certified as a Standard Reference Material, (2) purified (greater than 90 % SWCNT by
weight) bucky paper and (3) dispersed, length-sorted populations characterized by length. The instrumental
characterization of NIST's SWCNT reference materials is extensive, and this paper aims to provide researchers with
dispersion preparation methods for TEM (transmission electron microscopy) analysis of the SWCNT raw soot. A
selection of dispersing solvents, including organic solvents, aqueous surfactants and DNA dispersions, were prepared
and examined by TEM. Recommendations for sample preparation of the SWCNT SRM 2483 to yield images similar to
those presented here are given. Examples of images of the length-sorted SWCNT reference material are also shown.
These results illustrate the importance of optimal dispersion to enable imaging of SWCNT characteristics.
A detailed understanding of the crystallography of metallic conductors in modern interconnect systems is essential if
we are to understand the influence of processing parameters on performance and reliability. In particular we must be
able to evaluate the grain size, crystallographic orientation and residual elastic stress for interconnect lines having
widths of tens of nm. Transmission electron microscopy might be the obvious choice, but sample preparation and
small sample size make this technique unattractive. On the other hand, electron backscatter diffraction, EBSD, in a
scanning electron microscope provides a very attractive tool. Sample preparation can be relatively simple, especially
if one investigates the structures immediately after CMP; whole wafers may be measured if desired. One limitation
to EBSD is that good diffraction patterns are obtained only from free surfaces and from a limited depth, say a few
hundred nm in copper. Here EBSD will be used to compare structures for the pads and 100-nm lines in two variants
of a commercial copper damascene interconnect structure. EBSD data collection will be discussed as optimized for
characterizing differences in the texture, which were attributed to differences in the processing. By a unique
approach to EBSD mapping we found that neither the texture nor the grain size of the overburden, as represented by
the contact pads, propagated into the 100 nm lines, though they did propagate into some wider lines.
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