S.P. Arsenichev - Senior Lecturer, Department of Radiophysics and Electronics, V.I. Vernadsky Crimean Federal University (Simferopol) E.V. Grigoriev - Ph. D. (Eng.), Associate Professor, Department of Radiophysics and Electronics, V.I. Vernadsky Crimean Federal University (Simferopol) S.A. Zuev - Ph. D. (Eng.), Associate Professor, Department of Radiophysics and Electronics, V.I. Vernadsky Crimean Federal University (Simferopol) E-mail: sazuev@yandex.ru V.V. Starostenko - Dr. Sc. (Eng.), Professor, Department of Radiophysics and Electronics, V.I. Vernadsky Crimean Federal University (Simferopol) E-mail: starostenko@crimea.com E.P. Taran - Ph. D. (Eng.), Associate Professor, Department of Radiophysics and Electronics, V.I. Vernadsky Crimean Federal University (Simferopol) E-mail: taran_evgeniy@mail.ru I.Sh. Fitaev - Undergraduate, V.I. Vernadsky Crimean Federal University (Simferopol)

Thin conductive films are one of the main elements of modern chips. They are used in the chips as pads, contacts of semiconductor de-vices, connections between the active elements. In conducting films of a thickness exceeding 50 nm, the physical processes caused by currents and ohmic losses. For the analysis of electro-thermal processes is sufficient to use the wave equation and the heat equation. At thicknesses less than 50 nm in conducting films has spatial resonance. It is due to the physical properties of the films. Thus there is a transformation of energy of electromagnetic field into acoustic energy. The purpose of work is experimental investigation of spatial re-sonance in a thin conducting films of metal-dielectric structures (MDS) in a waveguide in the microwave range. When conducting experimental studies used a panoramic meter standing wave ratio (SWR) and attenuation (A) in the frequency range of 2.9 to 4.1 GHz, of 8.15 to 12.05 GHz and of 17.5 to 25.5 GHz. Metal-dielectric structure was a substrate of glass or glass-ceramic with a thickness of 0.5 mm foil of copper (Cu), aluminum (Al), nichrome (NiCr) and titanium (Ti). The surface of the substrate with the film of size 15×15 mm. To describe the characteristics of the reflected waves at inhomogeneities in the waveguide are used the standing wave ratio (SWR) and complex reflection coefficient (G). The transmission wave is determined by the attenuation (A). Along with SWR, G and A use optical coefficients: reflection (R), transmission (T), absorption (L). For film thickness d > 50 nm the values of SWR ≈ 2-2.5, and when d → 0 SWR → 1, G and R → 0. The coefficients A, T when the thickness of the film d < 50 nm are determined by the losses in the films - the conversion of electro-magnetic energy into acoustic energy. At such thicknesses the films reflected a little. Given the balance of power absorption (L) is un-iquely determined by the transmission coefficients (A, T). At metallo-dielectric structures with a film of aluminium high spatial resonance occurs when d ≈ 10 nm. The maximum conversion for MDS with a film of copper is found for d ≤ 5 nm. When placing a MDS close to the narrow wall of the waveguide (maximum of the values of magnet-term component of the H10 wave) MDS do not affect the wave propagation in the waveguide. These data allow us to conclude that the mechanism of transformation of the energies of the crucial role played by the electric component of the electro-magnetic field parallel to the film surface. The range of thicknesses, as well as energy conversion greatly depend on the technology of deposition of films. The shift to the max-imum value (at resonance) can reach more than 5 nm. The attenuation values during ion-beam and magnetron sputtering can vary 1.2-1.4 times. To calculate the distribution of currents in conducting films of MDS necessary to solve the problem of diffraction of electromagnetic field on the MDS. When solving the diffraction problem was used the method of minimum autonomous blocks and the finite difference time domain (FTDT). When developing the numerical model used an adaptive spatial step. Numerical calculations of SWR and attenuation, are carried out for MDS of copper, quantitatively coincide with experimental data. Calculations were made to thicknesses of films less than 100 nm. The distribution of the currents in its character depends little on the thickness of the films. The highest values of current density near the edges of the film parallel to the narrow walls of the waveguide decreasing towards the center of the film. The shift of the densities of the currents to the edges of the conductive film due to the Lorentz force acting on electrons of the Central regions of the films toward the side edges of the conductive structures. In nanometer films under the influence of powerful electromagnetic fields, currents are sources of dissipation that leads to the development of the breakdown in the middle of the films from the side edges to the center. This breakdown occurs in the film of copper or aluminum in thicknesses up to 500 nm when exposed to a powerful electromagnetic field. The paper presents results on the study of diffraction phenomena in thin films of MDS in the frequency range of 2.9 to 4.1 GHz, of 8.15 to 12.05 GHz and of 17.5 to 25.5 GHz. The main attention is on questions of conversion of energy of electromagnetic field into acoustic energy. Spatial resonance takes place in nanometer conductive films. The resonance phenomena are dependent on the thickness, material, and technology of film deposition. The distribution of current density in the conducting structures of the MDS is such that at high power densities of the forcing EMF, is the breakdown from the side edges of the film to the center. The results of these experimental studies are the source material for the development of the theory of spatial resonance in nanometric films when exposed to electromagnetic fields.

 

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