Using scanning near-field lithography (SNP), it is possible to pattern molecules at surfaces with a resolution as good as 9 nm [M. Montague, R. E. Ducker, K. S. L. Chong, R. J. Manning, F. J. M. Rutten, M. C. Davies and G. J. Leggett, Langmuir23 (13), 7328–7337 (2007)]. However, in common with other scanning probe techniques, SNP has previously been considered a serial process, hindering its use in many applications. IBM’s “Millipede” addresses this problem by utilizing an array of local probes operating in parallel. Here, we describe the construction of two instruments (Snomipedes) that integrate near-field optical methods into the parallel probe paradigm and promise the integration of top–down and bottom–up fabrication methods over macroscopic areas. Both are capable of performing near-field lithography with 16 probes in parallel spanning approximately 2 mm. The instruments can work in both ambient and liquid environments, key to many applications in nanobiology. In both, separate control of writing is possible for each probe. We demonstrate the deprotection of self-assembled monolayers of alkylsilanes with photocleavable protecting groups and subsequent growth of nanostructured polymer brushes from these nanopatterned surfaces by atom-transfer radical polymerization.

The current-induced interfacial reactions in the Ni/Sn-3.0Ag-0.5Cu/Au/Pd(P)/Ni–P (ENEPIG) flip chip interconnects and the failure mechanism during electromigration (EM) were reported. When ENEPIG was the cathode, EM significantly enhanced the consumption of Ni–P leaving a Ni3P layer; once the Ni–P was completely consumed, the growth of Ni2SnP was accelerated. The dissolved Ni atoms from the Ni–P and the interfacial intermetallic compounds (IMCs) were driven toward the anode upon electron current stressing and precipitated as large (Ni,Cu)3Sn4 IMCs. The excessive consumption of Ni–P and the formation of voids were responsible for the EM-induced failures. When Ni was the cathode, the rapid localized dissolutions of Ni under bump metallization (UBM) and Cu pad in the current crowding region resulted in a two-stage transformation of interfacial IMCs at the opposite Ni–P/solder interface. The localized dissolutions of Ni UBM and Cu pad on chip, as well as the formation of voids, were responsible for the EM-induced failures.

Nanocomposite Cr–Si–N films were prepared on to Ti–6Al–4V substrates by a novel duplex surface treatment technique. Coatings consisting of a Cr3Si surface layer were deposited using a double cathode glow plasma and subsequent surface plasma nitriding. The surface topography, chemical composition, and microstructure of these treated alloys were analyzed by a variety of surface characterization techniques. The resulting Cr–Si–N films consisted of nanocrystallite CrN grains embedded in amorphous SiNx phase. Nanoindentation tests showed that with increasing nitrogen partial pressure the hardness of the Cr–Si–N films increased and the elastic modulus decreased. Wear experiments showed that the Cr–Si–N films produced at a nitrogen partial pressure of 4.5Pa and 800 °C possessed the lowest wear rate and friction coefficient. Moreover, electrochemical measurements in 5 wt% HCl solution indicated that the Cr–Si–N films acted as an effective barrier against acid attack on the alloys.

Ternary electroless nickel, NiXP, films were produced by adding salts of Mo, Re, Tl, Cu, W, Co, Fe, Zn, and Mn to conventional electroless Ni baths and subsequently reacted with Sn-3.5Ag solder. From the full width at the half maximum (FWHM) data, as-plated NiXP films can be categorized into two groups: one is close to the FWHM value of nanocrystalline Ni5P film and the other is close to amorphous Ni9P film. Alloying elements in the electrolessly plated under-bump metallurgy that effectively suppressed intermetallic compound (IMC) spalling were Mn, Zn, Re, Fe, and W, whereas Tl exacerbated spalling. The roles of Cu, Mo, and Co were less clear due to a lack of data. Based on scanning electron microscopy observations, a spalling map was presented, which showed elemental demarcation lines of IMC spalling in the X-P coordinates.

Mg2Si1−xSnx compounds are promising as “environmentally friendly” thermoelectric (TE) materials. For years, investigations of the TE properties of these compounds have been hindered by the poor reproducibility in sample preparation. In this work, we used a recently developed simple B2O3 flux method to prepare Mg2Si1−xSnx compounds over a wide composition range (0.1 ≤x≤ 0.8). The phase structure, microstructure, and TE properties have been investigated. We found that a miscibility gap existed at 0.2 ≤x≤ 0.45, substantially lower than the more generally accepted values 0.4 ≤x≤ 0.6, and a low lattice thermal conductivity of 1.4 W·m−1·K−1 in undoped Mg2Si0.55Sn0.45, which led to a ZT ∼0.3 at 550 K. These results constitute a solid basis for investigating further optimization of the Mg2Si1−xSnx-based TE materials via doping and possibly nanostrucuring approaches.

In reactive templated grain growth (RTGG), oriented template crystals are used to seed both phase formation and crystallographic orientation in textured ceramics. This mechanism differs substantially from templated grain growth (TGG), in which texture forms via grain growth mechanism. In this work, characteristics of both RTGG and TGG processes are evaluated in [001] textured Sr0.61Ba0.39Nb2O6 ceramics produced from reactive SrNb2O6 and BaNb2O6 matrix powders and acicular KSr2Nb5O15 (KSN) templates. Above 1100 °C, SrxBa1−xNb2O6 (SBN) forms by oriented nucleation and growth on KSN (the RTGG process) and by nucleation of nonoriented matrix grains. RTGG occurs without densification or coarsening until phase formation is complete (∼1250 °C) and accounts for ∼60% of the texture in dense SBN ceramics. A later TGG process occurs from 1250–1350 °C and is characterized by simultaneous densification, grain growth, and additional texture development.

We report on the electrical and structural properties of boron-doped diamond tips commonly used for in-situ electromechanical testing during nanoindentation. The boron dopant environment, as evidenced by cathodoluminescence (CL) microscopy, revealed significantly different boron states within each tip. Characteristic emission bands of both electrically activated and nonelectrically activated boron centers were identified in all boron-doped tips. Surface CL mapping also revealed vastly different surface properties, confirming a high amount of nonelectrically activated boron clusters at the tip surface. Raman microspectroscopy analysis showed that structural characteristics at the atomic scale for boron-doped tips also differ significantly when compared to an undoped diamond tip. Furthermore, the active boron concentration, as inferred via the Raman analysis, varied greatly from tip-to-tip. It was found that tips (or tip areas) with low overall boron concentration have a higher number of electrically inactive boron, and thus non-Ohmic contacts were made when these tips contacted metallic substrates. Conversely, tips that have higher boron concentrations and a higher number of electrically active boron centers display Ohmic-like contacts. Our results demonstrate the necessity to understand and fully characterize the boron environments, boron concentrations, and atomic structure of the tips prior to performing in situ electromechanical experiments, particularly if quantitative electrical data are required.

Depending on the Ni:Co molar ratio, composites of NiCo/carbon nanorods and NiCo/carbon nanotubes can be synthesized through catalytic decomposition of benzene at 500 °C over NiCo nanoparticles derived from sol–gel synthesis followed by hydrogen reduction. According to x-ray diffraction results, the average grain size of NiCo31 is 11.2 nm, whereas that of NiCo13 and NiCo22 is 24.9 nm. Field-emission scanning electron microscopic and high-resolution transmission electron microscopic images reveal that over NiCo13 and NiCo22, the carbon nanomaterials are mainly in the form of nanorods, whereas over NiCo31, they are in the form of nanotubes. The composites of carbon and NiCo alloy are highly stable in air and show soft magnetic property and almost equal coercivity. It is observed that the saturation magnetization is affected by the composition of NiCo alloy.

Silicon carbide nanowires (SiCNWs) (with diameters of tens of nanometer and aspect ratio well above 103), consisting of β-SiC one-dimensional single crystals wrapped in amorphous nitrogen-containing SiO2 sheaths, were efficiently synthesized in gram quantities by autogenous combustion synthesis using Si as a defluorination reagent of poly(tetrafluoroethylene). The combustion temperature was evaluated using the emission spectroscopy. Vapor–liquid–solid mechanism of a self-catalytic growth of the SiCNWs is proposed.

This article lays the foundation for the development of microwave plasma chemical vapor deposition process conditions for synthesizing multilayered microcrystalline and nanocrystalline diamond (MCD and NCD) thin films. The effects of gas composition and the diamond seeding medium are correlated with the film morphology and diamond phase purity. Results of process optimization experiments using single-layer diamond deposition indicate that for high gas-phase Ar content (≥90%) the film quality improves with reduced Ar content and with increasing thickness reaching a plateau above a thickness of ∼2 μm. Multilayer diamond deposition experiments with two different seeding media (25 nm and 1 μm) clearly show that it is feasible to selectively synthesize alternating MCD (60% Ar) and NCD (95% Ar) layers with good control of film quality and morphology, thereby setting the stage for development of multilayered diamond thin films with tailored properties for thermal management applications.

Graphitic carbon (GC) is prepared using an ion-exchange resin as carbon source at 600 °C. A Co salt is selected as the graphitization catalyst and is pre-exchanged onto the resin during the ion-exchange process. The GC is characterized by transmission electron microscopy, x-ray diffraction, Raman spectroscopy, and thermogravimetry. Analysis of the crystallization shows that graphitization can occur at a temperature of as low as 600 °C, compared to the usual temperature of above 2000 °C in industry and above 1000 °C in literature. Different carbon structures have been found for different pretreatments of the resin and different heat treatment temperatures. This energy-saving method is an important breakthrough for the economic mass production of GC.

An oleylamine-assisted solvothermal approach has been developed for the synthesis of nickel hydroxide nanomaterials. α-Ni(OH)2 flower-like spheres and β-Ni(OH)2 hexagonal sheets were obtained by tuning the water volume in the synthesis system. The water-induced phase and morphology evolution from α-Ni(OH)2 spheres to β-Ni(OH)2 sheets were investigated in detail by controlled experiments based on their crystal structures. Moreover, NiO spheres and sheets were obtained by direct thermal decomposition of corresponding nickel hydroxides. N2 adsorption/desorption, temperature-programmed reduction with H2, and catalytic activity tests reveal that NiO spheres exhibit higher surface area, larger pore volume, higher reducibility, and better catalysis activities for CO oxidation than NiO sheets.

Anelastic recovery of pure magnesium was monitored quantitatively by means of acoustic emission (AE) in cyclic compression–quick unloading–recovery process. The influences of grain size, strain rate, and the strain-controlled cyclic process on anelastic recovery were analyzed in details. A detwinning model in anelastic recovery process was proposed, and the results showed good agreement with the experimental data. Three stages of anelastic recovery behavior as a function of strain were observed: stages I and III were considered to be dominated by various detwinning processes and stage II was dominated by thermal motion of dislocation. A quantitative relationship between anelastic recovery strain and AE signals was obtained, and from which the anelastic recovery strains from dislocation motion and detwinning were separated for the first time. In the strain-controlled cyclic process, both the amount of AE signals and the anelastic recovery strain were observed to decrease while the fraction of anelastic recovery strain from dislocation motions was observed to decrease more rapidly than that from detwinning with increasing cyclic number.

Over a long period (>10 years), the prediction of iron/mild steel corrosion in concrete requires the use of a mechanistic approach. For that purpose, a key point of the mechanisms involved is the localization of the oxygen reduction sites within the thick corrosion layers, which may greatly influence the nature of the rate-limiting step. In this context, iron rebars (originally covered with concrete) were sampled from a 50-year-old historical building and submitted to isotopic tracers methods (18O) combined with structural Raman microspectroscopy analyses on transverse sections. By this method, the authors demonstrate that the oxygen reduction sites are strongly impacted by the presence of a conductive phase (magnetite) in contact with the metallic substrate.