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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.

The theoretical results obtained are suitable for comparative analysis of electric activity of dielectric materials in vacuum. Their volume properties and charge in the surface (uncompensated ones or the presence of regular active lattice centers, etc.) were taken into account.

A calculation of the potential barrier shape at the metal-vacuum interface was carried out taking into account the effects of the spatial dispersion and dynamic corrections to the image force potential. The calculations were carried out using the random phase approximation (RPA) (for the concentration of conductivity electrons n or=1021 cm-3. Current-voltage characteristics were obtained for field emission both from the bulk material (with a non-quantized electron spectrum) and from thin films (with quantized electron spectra). The field emission (FE) from the thin films was shown to increase substantially due to the effective decrease of the work function. The quantization of electron spectra in quantum wells and, consequently, the decrease of the work function lead to a substantial increase of FE from planar and non-planar emitters covered by thin metallic films. The combined influence of the emitter shape and electron spectrum quantization on FE properties can be pronounced even under moderate and low external fields. The effect of the cathode shape on the emission properties was also analysed. The results obtained make it possible to optimize the structure and the shape of emitter tips for the tip array structure production.

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

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.

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).

A theoretical analysis is made of the effect of field emission from films with a quantized electron spectrum. Dependences of emission current on film thickness demonstrate oscillatory behavior due to oscillations in screening constant. Certain critical thicknesses are found at which the jumplike changes in the value of field emission intensity occur. It is shown that a large positive effect (increase of the field emission efficiency) may be obtained for the case of nonplanar emitters covered by thin quantized films due to the superposition of two important factors (electric field strengthening near emitter tips and electron spectrum quantization in the film).

Polarization and barrier potentials for the point charge at a metal–vacuum interface have been calculated in the Thomas–Fermi and random phase approximations taking into account spatial dispersion effects and quantum nature of conduction electrons. The effect of external field penetration into the metal on the barrier potential shape and emission current is demonstrated. Both isotropic (a spherical Fermi surface) and anisotropic (a flat Fermi surface) cases are considered. Comparison between these cases is made for equivalent conditions.