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The successful fabrication of field emission (FE) devices is directly related to process simplicity and device performance, which depends to a large extent on the tip material and emitter geometry. On the other hand, these characteristics are the most important issues influencing industrial applicability of the FE devices. In most typical solutions single emitter cells consist of a sharp tip located in the hollow, with the tip apex surrounded by a gate. The fabrication process described here is simple and allows self-aligned gate electrode formation. The field emission of the emitter tips is supported by a 50-nm diamond-like-carbon (DLC) film formed by chemical vapor deposition.

E cient engineering of metamaterials involves modeling of electric eld pro les around these structures. Realisticmodeling of the electric eld in metamaterials requires accurate knowledge of optical constants of the compo-nents for which traditionally the bulk values are taken. Further progress in the developing of metamaterials ischaracterized by a reduction of the pattern size, dimensions of single layers in multilayered structures etc. Ithas been understood that optical functions in low-dimensional and nano-sized materials substantially di er fromtheir bulk values increasingly a ecting by quantum processes. In this work we develop a complex method foranalytical modeling of electric eld pro les in metamaterials including quantum processes in nano-sized multi-layered structures. In particular based on rst principles density functional theory we obtained simple analyticalfunctions allowing predictions the optical functions variations with the size reduction of single metamaterialcomponents over a wide spectral region. It is shown that optical functions of nano-sized lms substantially (by50 percent and more) di er from those in bulk. The new calculated optical functions of the components areused for electric eld pro le modeling of nano-sized multilayered structures by nonlocal Green function techniqueincluding e ects of spatial dispersion. Silicon, silicon dioxide, and water layers are used as an example. Themethod e ectively incorporates real atomic structure reconstruction on surfaces and inner interfaces thus pro-viding with a more realistic picture for modeling. By comparison with experiment it is demonstrated that ourmethod predicts image potential of the nanostructures in better agreement with experiment than if using tradi-tional classic electrodynamics approach neglecting the quantum e ects. The results are discussed in comparisonwith literatureKeywords: Non-local electrodynamics, image potential, nano-structures, density functional theory.

Effects of the annealing in oxygen on the chemical composition and electron work function of Ba-Si and BaO-Si structures were studied. Thin Ba or BaO layers deposited onto silicon stimulate oxidation processes on the semiconductor surface. Treatment of the Ba-Si and BaO-Si samples at temperatures Ts≥500°C leads to the formation of a barium orthosilicate (Ba2SiO4) layer. A decrease in the electron work function observed for the silicon surface coated with both barium oxide and barium silicate layers provides for a more than tenfold increase in the electron emission current.

The structural and total interaction potentials of the vacuum space between two dielectric quartz crystal slabs of symmetric volume features but asymmetric surface features were calculated with Green’s function applied to the non-local Poisson equation.

The structured component DeltaVst(roarr) of the full potential formed between two dielectrics (semiconductors) in a small vacuum interval is calculated theoretically. The analytical expressions for DeltaVst(roarr) in the vacuum gap is calculated, using the Green's functions of the nonlocal Poisson equation. It is shown that the structured component DeltaVst(roarr) in the case of the small separated interval L~0.3-2 nm determines the lateral changing of the potential barrier height in the vacuum gap, which can result in the origin of the ordered long-period lattice of the areas of the decrease (increase) of the full potential inside a vacuum interspace. This fact can lead to the origin of the cold field emission canals, which are stimulated by the microscopic structure of the anode surface. If the cathode-anode vacuum distance is increasing (L4rarrinfin) the origin of the emission centers at the cathode surface is connected only with the microscopic structure of its surface

The opportunity of use nanostructural heterostructure n-SnO/sub 2/(Ni)/p-Si as a gas sensitivity element is investigated. The second derivative of the current-voltage characteristic of the heterostructure under influence of changes of gas environment and temperature were studied.

Heterostructures based on the nanometer-scaled semiconductor oxides can be used as gas-sensitive receptor and transducer systems. In comparison to resistive oxide sensors, having a linear current - voltage characteristics, the sensors based on the heterostructures show non-linear current - voltage characteristics. These structures, based on the industrially developed silicon technology, promise the new remarkable capabilities for the creation of the gas- and biosensitive sensors.

A very promising way in solid-state gas and bio-sensors creation is the use of well developed silicon technology for the manufacturing of the gas sensors. It will allow to unify the processes of the sensor production with the processes of the manufacture of the information processing circuit. This approach promises the essential abatement of the cost of devices and significant advantages in creation of the matrix sensors. The metal-silicon contacts perform the certain interest in such researches because they are the cheapest among semiconductor sensors. At the same time they provide sensitivity to gas environment due to strong dependence of their characteristics on the outside environment. In this work we present results of the usage of non-linear properties of the current-voltage characteristics diode-like structures which allow to extend capabilities of the described above approach for creation new type of sensors structures.

The diffusion barrier capabilities of thin layers of barium silicate, which are determined by the interaction between the YBaCuO compound and Si substrate, have been investigated. Analysis of the films' elemental depth distributions show that their interaction with the substrates result in the formation of a Ba/sub 2/SiO/sub 4/ layer. The superconducting characteristic of YBaCuO films obtained on barium silicate, in terms of transition width and T/sub c0/, are significantly improved compared to those without buffering. >

In the article the results of the influence of some types of biological molecules and their specific immune complexes on the volt-amperic characteristics of surface-barrier contact structures with the super thick metal film are presented. Moreover, the possibility to develop on this basis a simple instrumental method for separate registration of initial components and products of their interaction is discussed. It was shown that the volt-amperic characteristics of surface-barrier structures of Ni-Si changed at the deposition of myoglobin and its specific monoclonal antibodies. These structures more essentially reacted to the formed presence of specific immune complex and, in particular, to the direct formation of this complex on the surface at the subsequent use of the initial immune components in comparison with their separate presence. For all investigated types of biological molecules and their specific complexes we found optimal thickness of metal film when changes of volt-amperic characteristics of system achieved maximum level. It was concluded that this electrometrical method was suitable for the express and separation free registration of specific immune complex.

Superconducting YBaCuO thin films on GaAs substrate have been reproducibly prepared by the high-pressure RF magnetron sputtering without futher anneling. A buffer silicide layer to prevent the degradation of GaAs during YBaCuO film deposition. Superconducting YBaCuO thin films with a highly c-axis orientation perpendicular to the substrate surface, zero-resistance temperature of 83 – 85 K, and critical current density of 5.10 A/cm2 at 77 K have been achieved in our experiments. In these structures the interdiffusion between YBaCuO films and GaAs substrate is limited.

An electron emission behavior of field emission arrays based on a new bulk/surface silicon micromachining method of fabrication was studied. The process developed is simple and allows self-aligned gate electrode formation. The field emission of the emitter tips is enhanced by a 50 nm diamond-like carbon (DLC) film formed by chemical vapor deposition. Detailed Raman, Auger, and transmission electron microscopy (TEM) investigations of the deposited DLC films will be presented. Results about the presence of nanocrystalline diamond obtained with Raman spectroscopy could not be confirmed by the TEM investigations (the nanocrystalline diamond is smaller than 10 nm).

The extremal operating states of the active elements of integrated circuits and discrete devices as well as the different actions on semiconductor devices with a Schottky barrier based on metal silicide-silicon contacts lead to a change in their physical parameters. In this work the effect of impulsive overloads on a formed platinum silicide-silicon contact is studied. It is shown, with the help of analytical expressions for the currents in the superbarrier region and in the region of resonant tunneling charge transfer, that under impulsive action a change occurs in both the transitional layer and in the region of space charge; the change is associated with the increase in the concentration of deep levels in the region of space charge that participate in the resonance tunneling. Estimates of the Joule heating by the current flowing in the structures employed do not exceed 100°C, indicating that defect formation under the impulsive actions is nonthermal.

By solving for the potential barrier profile in metal-amorphous silicon contacts using an exponential distribution of the density of states in the energy spectrum mobility gap, we compute the voltage-current characteristics of such contacts taking into account tunneling through the space charge region. We demonstrate that as the density of states in the middle of the mobility gap increases, such tunneling leads to significant changes in the rectifying properties of a metal-amorphous silicon contact.

In the paper an analytic calculation is carried out of the volt-ampere characteristics of a Schottky barrier diode on amorphous silicon for an exponential distribution of the density of localized states in the mobility gap of α-Si. Explicit expressions are written for the volt-ampere characteristics with and without the inclusion of the image forces. It is shown that taking into account the image forces in the case of an intimate contact can lead to a substantial increase in the reverse currents through the diode, at the same time changing slightly the slope of both the forward and reverse branches of the volt-ampere characteristics plotted on a semilogarithmic scale.

Results are presented of an investigation of the possibility of realizing the tunnel-resonance current transport mechanism in metal-semiconductor junctions. From an analysis of the temperature dependence of the current-voltage characteristic, it is concluded that the experimental singularities being observed in titanium-palladium-doped silicon junctions correspond to effects predicted by the theory of tunnel-resonance charge transport mechanism.