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The exploitation of optical properties and phenomena are naturally done with nanoproducts that are primarily surface oriented, such as nanofilms, or alternatively phrased, the purpose of many surface-oriented nanoproducts has to do with optical properties—self-cleaning, antimicrobial, and so forth. Primary strength properties are normally a less important consideration in nanocoatings than are other properties. The general need and desire to keep surfaces clean and free of dirt has been long. In medical facilities, the need to keep surfaces from contributing to the spread of bacteria is obvious—hence the need for surfaces that are easy to clean or that have antibacterial or antimicrobial properties. Other functional needs related to surfaces include abrasion and scratch resistance. A successful quest for self-healing or self-repairing surfaces that recall similar behaviors in the skins of humans and animals would provide an enormous benefit to all. Materials with special behaviors related to light and color also have widespread applicability.

This chapter highlights the various aspects of materials such as classes, structure and properties. Metallic materials consist principally of one or more metallic elements, although in some cases small additions of nonmetallic elements are present. Examples of metallic elements are copper, nickel, and aluminum, whereas examples of nonmetallic elements are carbon, silicon, and nitrogen. Ceramic materials are composed of at least two different elements. Among the ceramic materials, one can distinguish those that are predominantly ionic in nature (these consist of a mixture of metallic elements and nonmetallic elements) and those that are covalent in nature (which consist mainly of a mixture of nonmetallic elements). In the Bohr atomic model, there is a nucleus consisting of protons with a positive charge and a mass of 1.67 × 10 -27 kg and neutrons with no charge but with the same mass as the protons. Composite materials are formed of two or more materials with very distinctive properties, which act synergistically to create properties that cannot be achieved by each single material alone.

This chapter presents the broader context of nanotechnologies. The automotive industry is already one of the world's largest users of nanomaterials, and expectations are that uses will increase. General Motors was an early adopter in 2002 with its use of thermoplastic olefin nanoclay composites in running board step-assists. Intensive research is in progress on many other fronts, including propulsion and energy systems that use nanotechnologies. The automotive industry is by no means homogeneous, and drivers vary according to product type and market. In some companies with high-value products, the potential of small performance increments can and does justify extensive design and material innovations. In other companies, cost concerns dominate, and new materials will be less likely to be introduced in a widespread way unless their costs are on a par with or below those of conventional materials for equivalent performance levels. The role of nanomaterials and nanotechnologies in this area can be rather simply thought of with respect to basic systems and components (including propulsion and energy systems, suspension systems, and others), frame and exterior body components, interiors, and control and communication systems. Surface appearances, including finishing and painting, are invariably important for visible components.

Single-walled carbon nanotubes (SWCNTs) prepared by the HiPco process were purified using a modified gas phase purification technique. A TEM-STM holder was used to study the morphological changes of SWCNT ropes as a function of applied voltage. Kink formation, buckling behavior, tubular transformation and eventual breakdown of the system were observed. The tubular formation was attributed to a transformation from SWCNT ropes to multi-walled carbon nanotube (MWCNT) structures. It is likely mediated by the patching and tearing mechanism which is promoted primarily by the mobile vacancies generated due to current-induced heating and, to some extent, by electron irradiation.

An inverse Hall-Petch effect has been observed for nanocrystalline materials by a large number of researchers. This result implies that nanocrystalline materials get softer as grain size is reduced below a critical value. Postulated explanations for this behavior include dislocation based mechanisms and diffusion based mechanisms. In this paper, we report an explanation for the inverse Hall-Petch effect based on the statistical absorption of dislocations by grain boundaries, showing that the yield strength is both dependent on strain rate and temperature, and that it deviates from the Hall-Petch relationship at a critical grain size.

Metastable austenitic stainless steels may transform to martensite when subjected to cold rolling. Upon subsequent annealing the martensite reverts back to ultra-fine grained austenite. Based on this concept, nano/submicron austenitic grains have been produced in a 63% cold rolled commercial AISI 301LN subjected to annealing treatments at 600°C, 800°C and 1000°C for 1, 10 and 100 seconds.Transmission Electron Microscopy (TEM) observations show the formation of equiaxed austenitic grains as small as ∼ 200nm in samples annealed at 800°C, and a dramatic increase in grain size as the annealing temperature and duration is increased. Additional tensile tests indicate that samples annealed at 800°C for 1 second exhibit a yield strength of ∼ 740 MPa and an total elongation of ∼ 45%. This combination of strength and ductility is excellent exceeding those of conventionally annealed steels (σy=350 MPa; Ductility ∼ 40%) or cold-rolled steels (σy=650 MPa; Ductility ∼ 30%).Finally, a correlation between the observed grain sizes and mechanical properties, in particular the yield strength, is obtained. Preliminary analysis indicates that the Hall-Petch equation can satisfactorily relate the observed yield strength with corresponding grain sizes.

Cu interconnects have decreased in width and are at around 100 nm. A decrease in interconnect width have led to a predominately bamboo structured Cu lines. In Cu interconnects, void formation during high temperature is a reliability issue, and this study looks at the void formation behavior in damascene Cu interconnects with a predominately bamboo microstructure. First, the crystal texture and grain morphology of the Cu interconnects was observed. Then to determine the void formation behavior, in-situ Transmission Electron Microscopy (TEM) was performed. Voids that formed as a result of in-situ heating were analyzed in terms of preferential void formation sites and crystal orientation where voids formed. In bamboo structured lines, voids formed at the triple junction of grain boundary and Cu/diffusion barrier interface. The crystal orientation where voids nucleated was studied to identify diffusion paths during void nucleation and growth.

Understanding the mechanical behavior of nanoparticles has become a key factor for the success of many engineering applications. Classically, for polycrystalline materials one would expect an increase in the yield strength for smaller grain sizes according to the empirical Hall-Petch equation. However, at the nanoscale, this mechanism seems to break down. Despite the number of interesting papers published on this topic, controversy persists and consensus is still lacking. While this discussion is of great interest for polycrystalline nanoparticles, contemporary models for strengthening are inappropriate for single-crystal nanoparticles, which, altogether, pose a very different problem: the absence of grain boundaries to inhibit dislocations. In this context, we present a new model wherein the change in Gibbs Free Energy of an edge dislocation in a single-crystal particle provides a driving force for dislocation motion. These results show that dislocations become unstable and are spontaneously ejected from the particles below a certain critical size.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Thermal fatigue during processing of microelectronic devices is a general reliability issue of concern in the microelectronic industry. In particular, as devices continue to be downscaled, the relaxation mechanisms operating under thermal stresses are expected to change. In this study, the microstructure of 1.8 micron and 180 nm wide Cu interconnects was identified through Transmission Electron Microscopy (TEM) imaging. In addition, In-situ TEM heating, performed in both type of specimens, is used to observe the differences in dislocation dynamics under thermal stress. In-situ TEM observations show delamination and inhibited dislocation motion in 180nm Cu lines, whereas in 1.8 micron Cu lines, grain boundaries seemed to act as dislocation sources. These different deformation mechanisms are expected to have an impact on the thermal fatigue behavior of Cu interconnects as the scale of devices is brought below 100 nm.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

The relative contributions of various defects to the measured resistivity in nanocrystalline Cu were investigated, including a quantitative account of twin-boundary scattering. It has been difficult to quantitatively assess the impact twin boundary scattering has on the classical size effect of electrical resistivity, due to limitations in characterizing twin boundaries in nanocrystalline Cu. In this study, crystal orientation maps of nanocrystalline Cu films were obtained via precession-assisted electron diffraction in the transmission electron microscope. These orientation images were used to characterize grain boundaries and to measure the average grain size of a microstructure, with and without considering twin boundaries. The results of these studies indicate that the contribution from grain-boundary scattering is the dominant factor (as compared to surface scattering) leading to enhanced resistivity. The resistivity data can be well-described by the combined Fuchs–Sondheimer surface scattering model and Mayadas–Shatzkes grain-boundary scattering model using Matthiessen's rule with a surface specularity coefficient of p = 0.48 and a grain-boundary reflection coefficient of R = 0.26.

The deformation behavior of nanoscale metals continues to be an exciting area for materials research. However, in the case of single crystal 0-D nanoscale metals, no deformation experiments, to our knowledge, have been performed at the nanoscale. The one experiment closest to the nanoscale was an in-situ TEM compression of ~200 nm Si nanoparticles. However, the particle tested was too large to extract relevant information at the nanoscale and the mechanical deformation of Si is also expected to be different from that of metals. For nanoparticles it is claimed there is a conspicuous lack of dislocations, regardless of the materials processing history, even after significant deformation. Therefore, it has been suggested that dislocations cannot exist or/ do not play a role on the deformation of 0-D nanomaterials. To address this issue of the role played by dislocations in the deformation of 0-D nanomaterials, nanoparticles with diameters

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Atomically resolved structures and compositions of Pt alloy nanoparticles were obtained using aberration-corrected high-angle dark field imaging, which was correlated to specific ORR activity based on a Pt surface area. The enhanced specific ORR activity (approximately 2 times relative to Pt) of acid-treated "Pt3Co" nanoparticles can be related to composition variations at the atomic scale and the formation of percolated Pt-rich and Pt-poor regions within individual particles. Upon annealing, we show direct evidence of surface Pt sandwich-segregation structures, which correspond to a specific ORR activity approximately 4 times relative to Pt.

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

A mechanism for shape memory alloys driven by a magnetic field is proposed. The mechanism involves the motion of twin dislocations in response to the application of a magnetic field. As a consequence, twin variants oriented favorably with respect to the magnetic field direction will grow. The maximum pressure that can be exerted at the twin dislocations is when the magnetic field is at angle . The shape memory effect is significantly affected by the presence of impurities, second-phase particles and grain boundaries

The grain structure in Cu interconnects of the 45 nm node was analyzed to yield grain orientation and boundary characteristics using a high-resolution electron diffraction technique. A dominant sidewall growth of {111} grains was observed, reflecting the importance of interfacial energy in controlling grain growth below 70 nm linewidth. The grain structure was used to identify flux divergent sites for void formation under electromigration (EM) and to analyze the effect on EM statistics for Cu lines with CoWP capping using a microstructure-based model. This analysis established a correlation between the microstructure of Cu nanolines, void formation kinetics, and EM statistics.

The effects of neutron-induced damage on the ferroelectric properties of thin film lead zirconate titanate (PZT) were investigated. Two sets of PbZr0.52Ti0.48O3 films of varying initial quality were irradiated in a research nuclear reactor up to a maximum 1 MeV equivalent neutron fluence of (5.16 ± 0.03) × 1015 cm−2. Changes in domain wall mobility and reversibility were characterized by polarization-electric field measurements, Rayleigh analysis, and analysis of first order reversal curves (FORC). With increasing fluence, extrinsic contributions to the small-signal permittivity diminished. Additionally, redistribution of irreversible hysterons towards higher coercive fields was observed accompanied by the formation of a secondary hysteron peak following exposure to high fluence levels. The changes are attributed to the radiation-induced formation of defect dipoles and other charged defects, which serve as effective domain wall pinning sites. Differences in damage accumulation rates with initial film qual...

In this work, a recently developed electron diffraction technique called diffraction scanning transmission electron microscopy (D-STEM) is coupled with precession electron microscopy to obtain quantitative local texture information in damascene copper interconnects (1.8µm‐70 nm in width) with a spatial resolution of less than 5 nm. Misorientation and trace analysis is performed to investigate the grain boundary distribution in these lines. The results reveal strong variations in texture and grain boundary distribution of the copper lines upon downscaling. Lines of width 1.8µm exhibit a strong!111"normal texture and comprise large micron-size grains. Upon downscaling to 180 nm, a{111}!110"bi-axial texture has been observed. In contrast, narrower lines of widths 120 and 70 nm reveal sidewall growth of{111} grains and a dominant!110"normal texture. The microstructure in these lines comprises clusters of small grains separated by high angle boundaries in the vicinity of large grains. The fraction of coherent twin boundaries also reduces with decreasing line width. (Some figures may appear in colour only in the online journal)

Graphite oxide (GO) was discovered to catalyze the ring opening polymerization of various cyclic lactones and lactams, such as e-caprolactone, δ-valerolactone, and e-caprolactam, to their corresponding polyesters or polyamides. The resulting polymers were obtained in moderate number average molecular weights (4.8–12.8 kDa) and in good to excellent yields (39–100%) at GO loadings ranging from 2.5–20.0 wt%. Using powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM), it was determined that the carbon catalyst was retained and homogeneously dispersed within the polymer product, resulting in the formation of a carbon-filled composite. TEM also revealed that the carbon transitioned from the lamellar morphology found in GO primarily to nanometre-sized, multiwalled fullerenes; no other discrete carbon morphologies were observed. The inclusion of the carbon material in the polyesters was found to improve the mechanical stiffness of the polymers by up to 400%, as compared to the neat homopolymer.