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Artificial muscle fibers and compliant actuators are generating increasing interest from several advanced robotics applications. In this paper, we propose an integrated linear actuator design based on the synchronous linear motor concept and provide simulation data to assess its potential performance. The actuator is designed to be modular, scalable, flexible, devoid of permanent magnets, and physically structured to mimic natural muscle fibers. We use a straightforward actuation protocol to compare the force, stroke and other performance characteristics of the actuator with biological muscles. The thermal behavior is also simulated, including the effects of an integrated microfluidics cooling system that allow the force to mass ratio of a structure to increase. Results indicate such approach as a possible promising route to develop muscle like actuators in the framework of microelectronics technology.

The development of integrated sensors is a challenge currently facing biodiagnostics where multiplexing and high sensitivity detection are frequently required. This work follows an approach based on silicon photomultiplier detection, phosphorescent nanobeads and compact front-face light-source configuration. The advantages of this approach also derive from the sensitivity, compactness, robustness and low operating voltage of SiPM devices. An experiment was performed to demonstrate performance in terms of sensitivity, with the results allowing the estimation of a detection limit for proteins of 1–10 pg/mL.

A quantitative angle-resolved XPS analysis was carried out of the carbonaceous films resulting from the derivatization under mild thermal activation of nearly flat, terraced, dihydrogen-terminated, 1 × 1 (100) Si with 1-octene or 1-octyne. The analysis of the C 1s signal gave evidence for the presence of carbon in carbide configuration (SiC bonds) at the substrate–film interface, in addition to the alkanic carbon and adventitious oxidized carbon (CO bonds) produced by the oxidizing impurities flawing the reaction. Assuming the surface as uniformly covered, the analysis showed that for both reactants the films were closely packed. Copyright © 2006 John Wiley & Sons, Ltd.

A lot of work has been carried out to prepare chemically homogeneous (1 0 0) silicon surfaces. The hydrogen-terminated (1 0 0) silicon surfaces are the most promising ones, especially in view of their remarkable environmental stability. The simplest way to produce hydrogen-terminated surfaces (attack in water solution of HF of a sacrificial, thermally grown, oxide) results in strongly heterogeneous rough surfaces (although with prevailing dihydride terminations). These surfaces can, however, be flattened and homogenized by treating them in H 2 at high temperature ( > 850 ° C). The morphological and chemical changes undergone by the surface during the treatment are studied X-ray photoelectron spectroscopy, atomic force microscopy, scanning tunnelling microscopy, infrared absorption spectroscopy in the attenuated total reflection mode, reflection high energy electron diffraction and thermal programmed desorption, and the mechanisms responsible for them are discussed.

Denoting with 'nanodevice' any device with size in one dimension at least in the nanometre length scale (NLS), the basic constituent of integrated circuits (ICs), the metal-oxide-semiconductor (MOS) field-effect transistor (FET), is by several years a nanodevice. In fact, the thickness of the SiO"2 gate dielectric is around 3nm for logics or 5nm for nonvolatile memories. However, since the factors limiting the IC integration are horizontal sizes, in electronics one speaks of nanodevice when its size in one horizontal dimension at least is in the NLS. The definition of features in the NLS is impossible via optical lithography, but can be done using electron- or ion-beam lithography. These techniques, however, are very expensive and still in their fancy, at least for what concerns their exploitation in the industry practice. Geometries in the NLS can however be produced with relative ease by the spacer patterning technique, i.e., transforming vertical features (like film thickness) in the vicinity of a step of a sacrificial layer into horizontal features. The ultimate length producible in this way is controlled by: the steepness of the step defining the sacrificial layer; the uniformity of the deposited or grown films; and the anisotropy of its etching. While useful for the preparation of a few devices with special needs, the above trick does not allow by itself the development of a nanotechnology, where each layer useful for defining the FET should be in the NLS and aligned on the underlying geometries with tolerances in the NLS. Setting up such a nanotechnology is a major problem which will involve the IC industry in the post-Roadmap era. Irrespective of the detailed structure of the basic constituents of nanoICs (molecules, supramolecular structures, clusters, etc.), any nanoIC can hardly be prepared without the ability to produce arrays of conductive strips with pitch in the NLS. This work is devoted to describe a scheme (essentially based on the existing microelectronic technology) for their production without the use of electron- or ion-beam lithography and used as host of molecular devices.

An experimental study via X-ray photoelectron spectroscopy at different takeoff angles of the derivatization of atomically flat, hydrogen terminated, 1 × 1 (1 0 0) Si surfaces with 1-octyne is reported. The major conclusion of the experimental analysis (that a large fraction of the grafted moieties contain unreacted π bonds) is then compared with the results of high-level ab initio modelling with model molecules of the derivatization act.

An experimental study of the derivatization of Si(100) surfaces with 1-octyne has been carried out via x-ray photoelectron spectroscopy at different take-off angles, and infrared absorption spectroscopy in attenuated total reflection mode and atomic force microscopy have been used to characterize the pristine surface. Our study has shown that it is possible to prepare nearly flat, terraced, homogeneously hydrogen-terminated Si(100) surfaces via exposure to H2 at high temperature (1100 °C) and that these surfaces may be functionalized with hydrocarbon moieties by simple immersion in the unsaturated hydrocarbon at ∼200 °C. Copyright © 2004 John Wiley & Sons, Ltd.

Heating (100) silicon at high temperature (say, higher than 850 °C) in H2, cooling to 670–700 °C in the same ambient, and quenching to room temperature in N2 results in environmentally robust, terraced 1 × 1 (100) SiH2. Evidence for this conclusion is based on angle-resolved x-ray photoelectron spectroscopy, atomic force microscopy, infrared absorption spectroscopy in the attenuated total reflection mode, thermal programmed desorption, and reflection high-energy electron diffraction. Copyright © 2005 John Wiley & Sons, Ltd.

This work presents a study based on x-ray photoelectron spectroscopy of the reaction of hydrogen-terminated silicon with 1-alkynes as a route for the functionalization of the (100) surface of silicon. The study (i) demonstrates that the grafting of hydrocarbon moieties is possible by simple exposure of the silicon surface to a liquid alkyne, (ii) shows that the derivatization protects the silicon against oxidation in air, (iii) indicates that the process occurs via hydrosilation of the alkyne at the hydrogen-terminated surface and (iv) suggests that grafted moieties contain in large part an unreacted π bond.

An experimental study of the Si 2p XPS spectrum at different take-off angles of atomically flat, hydrogen-terminated 1 × 1 Si(100) is reported. The observed spectrum can be described accurately by considering three additional contributions to the spectrum of elemental silicon. Each contribution is attributed to a chemical state of silicon on the basis of its chemical shift with respect to elemental silicon and the depth of the region where it was originated. Copyright © 2003 John Wiley & Sons, Ltd.

The early oxidation stages of hydrogen-terminated single-crystalline Si(100) exposed to a diluted N2/N2O atmosphere at 850° C for different durations have been studied by XPS, following the evolution of the Si 2p signal. Evidence is given that the usual analysis, in terms of five pairs of peaks attributed to silicon in oxidation states from 0 to +4, does not account for the observed Si 2p signal. The spectrum is accurately reproduced only by assuming the existence of silicon in bonding configurations different from those usually assumed to occur at the Si/SiO2 interface. Copyright © 2002 John Wiley & Sons, Ltd.

Silicon oxide and silicon nitride surfaces have been treated with 1-octadecene at ∼200°C. The resulting film topography has been inspected by atomic force microscopy (AFM), showing a densely packed organic coating with a corrugation of some tenths of a nanometre. High-mass-resolution time-of-flight secondary ion mass spectrometry (ToF-SIMS) spectra from such surfaces display octadecene- as well as substrate-related peaks. Furthermore, peaks diagnostic of the formation of SiOC or SiC linkages are observed in the case of silicon oxide, whereas the same peaks and those due to SiNC species have been observed in the case of silicon nitride. These results suggest that 1-octadecene molecules are chemisorbed on the substrate. Contact angle measurements and AFMforce spectroscopy measurements allow comparison upon the macroscopic and nanoscopic scale, respectively, of the surface free energy modification due to the formation of the organic coating.

The demand for high sensitivity in microarray technology has stimulated the research of new labeling strategies, new substrates with increased loading capacity and new approaches to amplify the fluorescence signals. Although these methods improve the sensitivity, they are based on non-routine procedures which limit their widespread usage. A simple way to achieve fluorescence enhancement is the optical interference (OI) coating technology based on the use of substrates with films of well-defined thickness that maximize photoabsorption of the dye molecules in the vicinity of the surface and reflect the emitted light toward the detector. Here we introduce a new substrate for fluorescence enhancement composed of a thin aluminum mirror and a single quarter wave silicon oxide as a dielectric layer. The use of such material allows the development of a substrate suited for parallel production in conventional IC (Integrated Circuit's) technology, which produces a 20-fold enhancement of fluorescence compared to glass, which is the most common material used in microarrays. The new substrate was coated with a copolymer of N , N -dimethylacrylamide, N -acryloyloxysuccinimide, and 3-(trimethoxysilyl)propyl methacrylate, copoly(DMA-NAS-MAPS), which forms, by a simple and robust procedure, a functional nanometric film that covalently binds bio-probes on the surface and efficiently suppresses non-specific adsorption. The performance of the new fluorescence-enhancing substrate in microarray technology was demonstrated for the detection of a panel of inflammation biomarkers pushing detection limits into the femtomolar range.

An array of nanocavities in silicon offers an inner surface defined by nearly flat, highly ordered, planes which can be passivated by hydrogen injection from aqueous solution of HF. The infrared spectrum shows that the inner surface is mainly constituted by monohydrides in different morphologies. The corresponding signals are very narrow (full width at half maximum at room temperature below 5 cm-1, depending on the line), this being evidence for high local order. Such an inner surface can be used as a benchmark for the assignment of infrared signals observed on outer surfaces, where the sources of errors-and the consequent uncertainty in the spectral attribution-may be large. The comparison between the spectra from a well-characterized external Si(1 0 0) surface and from an internal one (in both cases hydrogen-terminated) has allowed a better qualification of the external surface. Copyright © 2010 John Wiley & Sons, Ltd.

An experimental study based on x-ray photoelectron spectroscopy of room-temperature oxidation in air of nearly flat, terraced, hydrogen terminated (100) silicon has been carried out. The oxidation kinetics are characterized by two temporal domains, essentially associated with the formation of the substoichiometric oxide and for its transformation into the stoichiometric oxide: the substoichiometric oxide grows (with kinetics that may described in terms of an autocatalytic process) showing saturation at about $5\ifmmode\times\else\texttimes\fi{}{10}^{14}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}2}$, while the stoichiometric oxide grows following a time logarithmic law. The entire process is characterized by the increase of a feature, with binding energy shifted by about $+0.3\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ with respect to that of elemental silicon, attributed to silicon atoms or clusters embedded in the growing oxide.

Among the processes devoted to the preparation of chemically homogeneous (100) silicon surfaces, the ones for hydrogen termination are the most promising, especially in view of the remarkable environmental stability of such surfaces. The simplest way to produce hydrogen-terminated silicon (attack of a sacrificial, thermally grown, oxide in aqueous solution of HF) results in rough, strongly heterogeneous (although with prevailing dihydride terminations) surfaces. These surfaces can, however, be flattened and homogenized by treating them in ${\mathrm{H}}_{2}$ at high temperature $(g850\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C})$. The morphological and chemical changes undergone by the surface during the treatment are studied ex situ (via x-ray-photoelectron spectroscopy, atomic force microscopy, scanning tunneling microscopy, infrared absorption spectroscopy in the attenuated total reflection mode, reflection high-energy electron diffraction, and thermal programmed desorption) and the mechanisms responsible for them are discussed.

The early oxidation stages of hydrogen-terminated single-crystalline (100) silicon exposed to a diluted N2 : N2O atmosphere at 850°C for different durations have been studied by x-ray photoemission spectroscopy, following the evolution of the Si 2p signal. Evidence is given that the usual analysis, in terms of five pairs of peaks attributed to silicon in the oxidation states from 0 to +4, does not account for the observed Si 2p signal. An explanation for silicon in unusual oxidation states is proposed.

Time-of-flight SIMS profiles have been obtained on an SiO 2 /Si system. A dual ion beam experimental set-up has been used in order to decouple the erosion process due to an Ar + beam from the analysis done by a Ga + beam. The Ga + yield shows a characteristic double-peaked structure at the SiO 2 /Si interface. It is shown that the peak at shallower depth can be accounted for by a change in sputtering rate, whereas that located at the interface can be interpreted in terms of gallium segregation.