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Monolayer membranes of conjugated carbon represent a class of nanomaterial with demonstrated uses in various areas of electronics, ranging from transparent, flexible, and stretchable thin film conductors, to semiconducting materials in moderate and high-performance field-effect transistors. Although graphene represents the most prominent example, many other more structurally and chemically diverse systems are also of interest. This article provides a review of demonstrated synthetic and integration strategies, and speculates on future directions for the field.

Understanding the biophysics governing single-molecule transport through solid-state nanopores is of fundamental importance in working toward the goal of DNA detection and genome sequencing using nanopore-based sensors. Even with significant advances in semiconductor fabrication technologies, the state-of-the-art in nanopore technology still falls well short of mimicking the elegance and functionality found in biology. Kasianowicz et al.[1] pioneered the first in vitro studies of biomolecule transport through single nanopore channels by translocating individual ssDNA and ssRNA molecules through α-hemolysin protein pores inserted into a lipid bilayer membrane. More recently, focus has shifted to the solid-state domain with numerous groups studying biomolecule transport through solid-state nanopores.[2-7] Solid-state nanopores exhibit superior chemical, thermal, and mechanical stability over their biological counterparts, and can be fabricated using conventional semiconductor processes, thereby facilitating mass fabrication and size tunability. They are typically formed in thin Si3N4 or SiO2 membranes using a combination of decompositional ion/electron-beam-based sputtering and surface-tension-driven shrinking processes.[2,4,7] Other techniques for creating individual nanopores include the track-etch method for the formation of conical nanopores in polycarbonate membranes.[8] The translocation of negatively charged DNA molecules through these nanometer-sized solid-state pores is conventionally performed using two-terminal electrophoresis, resulting in characteristic blockades in the measured ionic current. This technique has been used to study various physical phenomena at the single-molecule level, including unzipping kinetics of hairpin DNA,[9] detection of single-nucleotide polymorphisms,[10] stretching transitions in dsDNA,[11] biomolecule folding,[3] discrimination of long DNA molecules based on length,[12] and nanopore-based DNA force spectroscopy.[13] Though this technology shows much promise, major hurdles still remain. Fabrication challenges (stress-induced membrane deformation and mechanical failure in SiO2 structures),[5] limited nanopore lifetime, electrical noise,[14,15] and a lack of chemical specificity limit the feasibility of this technology in high-end applications such as DNA sequencing. Thus, there is a need for highly sensitive, mechanically robust nanopore sensors with well-defined surface-charge properties for the detection of specific biological molecules (ssDNA, dsDNA, mRNA).

This paper presents new results on the deposition technique and the characterization of thin (ZrO 2 ) x (Al 2 O 3 ) 1 - x layers on silicon. The layers were deposited using the chemical solution deposition method on silicon substrates, and they were then subjected to different temperature treatments. For comparison, pure ZrO 2 layers were deposited, too. The chemical composition of (ZrO 2 ) x (Al 2 O 3 ) 1-x layers is determined by Rutherford Back Scattering. The morphology was studied by HRSEM. The addition of Al 2 O 3 makes the layers structurally more homogeneous as compared to those of pure ZrO 2 . The electric properties of MIS structures were studied. A fixed negative charge and the high dielectric constants are characteristic for these layers. The experimental results are discussed in the context of using them as high-k dielectrics.

Possible sources of silicon and carbon atoms built-in amorphous hydrogenated silicon carbide thin films grown by reactive magnetron sputtering (RMS) in argon/methane gas mixtures are evaluated. It is found out that the plasma decomposition of methane molecules plays an essential role in providing of growing film surface by active hydrocarbon fragments, thus influencing significantly the film stoichiometry even though the methane partial pressure in the sputtering gas mixture is only 1.5–4.7%.

Li-ion batteries are promising candidates for electrical energy storage in applications ranging from portable electronics to hybrid and electric vehicles. In this context, layered compounds in the Li(1+delta)(TM(x)Mn(1-x))(1-delta)O(2) family (TM = transition metal) have received much attention due to their high capacity and stability. In this Research News article we describe recent advances on structural characterization of Li-ion electrode materials using state-of-the-art electron microscopy. Direct evidence of the monoclinic nature of Li(2)MnO(3) has been provided. It has been demonstrated that differences in Z-contrast imaging between Li(2)MnO(3) and LiTMO(2) may be used to screen samples for phase separation in the 10-100 nm scale.

A comparative investigation is carried out of the discharge characteristics (current-voltage characteristic and dependence of the running voltage on the gas pressure at constant discharge current), as well as of some plasma parameters (electron temperature, floating potential and plasma potential) and densities of the ion current extracted to the substrate, for discharges in neon and argon in a planar magnetron system for sputtering with a graphite target.

The behaviour of the ratio of the argon ion flux and the sputtered atom flux to the substrate with the variation of the basic process parameters was studied in a planar magnetron sputtering system. Finding ways to control this ratio is important with respect to carrying out ion-assisted thin film growth by magnetron sputtering under well-defined conditions. Combined deposition rate measurements and plasma probe measurements were carried out in order to determine the ion/atom arrival rate ratio. In addition calculations of the neutral atom flux were performed on the basis of a simple model and the results compared with the measured values. A considerable change in the values of the ion/atom arrival rate ratio with the variation of the argon pressure and the discharge power was found under operating conditions, at which the back diffusion of the sputtered material is pronounced. The distribution of the ion flux over the substrate surface was found to become more homogeneous with the increase of the working pressure or the target-to-substrate distance.

The characteristics of the plasma surrounding the substrates in a planar magnetron sputtering system with a graphite target have been investigated by electrostatic probe measurements. The behaviour of the ion density ni and the electron temperature Te, determining the ion flux that can be extracted by the substrate, with the variation of the basic system parameters, has been studied.