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Data generated in the characterization and analysis of the Zinc Tin Oxide thin films (as shown in the Figures in the manuscript)EPSRC [EP/M013650/1
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Optical characterization of sol–gel deposited lanthanum nickel oxide, LaNiO3 (LNO) film on Pt-coated Si substrate was performed by spectroscopic ellipsometry and reflectometry. The sum of five Lorentz oscillators was used for LNO... more
Optical characterization of sol–gel deposited lanthanum nickel oxide, LaNiO3 (LNO) film on Pt-coated Si substrate was performed by spectroscopic ellipsometry and reflectometry. The sum of five Lorentz oscillators was used for LNO dispersion parameterization in spectral range from 190 to 1000nm. Two theoretical approaches: Raileigh–Rice theory (RRT) and effective medium approximation (EMA) were considered to account for the effect of
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Spectroscopic ellipsometry (SE) is used to study a sinusoidal-relief grating fabricated on a surface of transparent polymer. An optically thick polymer layer is situated on a glass substrate and its refraction index is optically matched... more
Spectroscopic ellipsometry (SE) is used to study a sinusoidal-relief grating fabricated on a surface of transparent polymer. An optically thick polymer layer is situated on a glass substrate and its refraction index is optically matched to the index of the glass. The rigorous coupled-wave analysis, implemented as the airy-like internal reflection series, is applied to calculate the optical response of
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A novel 1D conical nanotubular CdS/TiO2 heterostructure possesses synergic effects that yield a superior photon-to-electron conversion and shows promising perspectives in photovoltaics.
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ABSTRACT We report on spectro-ellipsometric investigations of reactively sputtered tantalum nitride (TaNx/SiO2) and vanadium nitride (VN/Si) films. Several TaNx layers with different deposition temperatures (200–400 °C) and a VN layer... more
ABSTRACT We report on spectro-ellipsometric investigations of reactively sputtered tantalum nitride (TaNx/SiO2) and vanadium nitride (VN/Si) films. Several TaNx layers with different deposition temperatures (200–400 °C) and a VN layer were prepared optically thick and analyzed using the bulk formula. For thin TaNx layers prepared with the same temperatures as thick layers, the Drude–Lorentz parameterization of dielectric functions was used by simultaneous fitting of ellipsometric and optical transmittance spectra. VN pseudo-dielectric functions show strong metallic character, which is typical for other transition metal nitrides. In contrast, the TaNx dielectric constants obtained here range from a metallic to a non-metallic character depending on substrate temperature, but independent of the film thickness. This substrate temperature dependence may be due to multiple phases in the TaNx films.
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ABSTRACT Complex film structures, such as multilayer and gradient films, were deposited using tetravinylsilane monomer by plasma-enhanced chemical vapor deposition. The optical and mechanical properties of the deposited film were... more
ABSTRACT Complex film structures, such as multilayer and gradient films, were deposited using tetravinylsilane monomer by plasma-enhanced chemical vapor deposition. The optical and mechanical properties of the deposited film were controlled by the effective power if pulsed plasma was used. Functionally nanostructured films with zigzag, step, and gradient distributions of optical and mechanical properties across the film were constructed in one deposition using time-dependent effective power. The optical and mechanical properties of the deposited films were investigated by spectroscopic ellipsometry and cyclic nanoindentation measurements, respectively. Analyses confirmed expected patterns of optical properties across the film structures. Controlled deposition of tailored films is a new technological step for the creative design and application of complex film structures in smart materials and devices.
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The rigorous coupled wave analysis (RCWA) implemented as the Airy-like internal reflection series (AIRS) is applied in a theoretical analysis of the optical response of diffraction gratings. Detailed theoretical description of the RCWA... more
The rigorous coupled wave analysis (RCWA) implemented as the Airy-like internal reflection series (AIRS) is applied in a theoretical analysis of the optical response of diffraction gratings. Detailed theoretical description of the RCWA with respect to the AIRS implementation is provided, including the application of Li's Fourier factorization rules and the recursive algorithm for sliced relief gratings. Numerical analysis of convergence properties including computation time is demonstrated for structures made of transparent, semiconductor, or metallic materials.
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ABSTRACT Spectro-ellipsometric measurements were carried out on pulsed laser irradiated c-Ge surfaces. Numerical analyses indicated two possible parameterizations of the surface layer modeled by effective medium approximation. One... more
ABSTRACT Spectro-ellipsometric measurements were carried out on pulsed laser irradiated c-Ge surfaces. Numerical analyses indicated two possible parameterizations of the surface layer modeled by effective medium approximation. One solution was found for effective layer thickness of approximately 20 nm and Ge filling factor of approximately 7%. Effective layer thickness of second solution was approximately 8 nm and corresponding filling factor of Ge was approximately 53%. Surprisingly, the solution with small filling factor was found consistent with SEM measurement in which nano-dots were regularly arranged in one-dimensional parallel lines with the period of 1 μm.
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ABSTRACT Pulsed Laser Deposition of magnetically ordered polycrystalline SmFeO3 films has been optimized onto SiO2 glass substrates as function of substrate temperature, oxygen pressure and pulsed laser fluency. Using a KrF excimer laser,... more
ABSTRACT Pulsed Laser Deposition of magnetically ordered polycrystalline SmFeO3 films has been optimized onto SiO2 glass substrates as function of substrate temperature, oxygen pressure and pulsed laser fluency. Using a KrF excimer laser, crystallization temperature is found to be about 1048 K for a weak fluency of only 1.7 J cm− 2. We show that this growth temperature can be reduced using higher fluency and that it is possible to obtain a film texturation along the c axis by reducing the oxygen pressure at given temperature and fluency. In a second part, we focus on the SmFeO3 optical constants determined by in situ ellipsometry using a stacking model and the Cauchy dispersion relation for SmFeO3 layer. We show a good correlation between the transmission and reflection calculated from these data and measured by ex situ spectrophotometry in the visible range.
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The physical principle of proposed sensor is based on the combination of two effects: the modulation of permittivity tensor elements in materials with induced anisotropy by external magnetic field and the creation of sharp minima in... more
The physical principle of proposed sensor is based on the combination of two effects: the modulation of permittivity tensor elements in materials with induced anisotropy by external magnetic field and the creation of sharp minima in reflectance on prism base at guided mode resonance. As result we can observe pointed up the polarization states of reflected light beam influenced by external magnetic field.Procedures based on the Yeh’s 4×4 matrix formalism are described for the treatment of the electromagnetic interactions in prism-layered or -bulk structure with magnetic ordering. The tunneling phenomenon between coupling prism and inspected object is analyzed for ultrathin approximation and for the case of a gap spacing wide enough so that the prism could be considered as weak perturbation to the modes of the free structure. The value of Kerr rotation at resonant states achieves to one radian. Its dependence on in-plane modulation of magnetization direction offers the possibility to realize the magnetic vector sensor with angle distinguishing better than one degree.
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ABSTRACT AFM, XRD, zeta (ζ) potential measurement and spectroscopic ellipsometry were used for characterization of thin (20nm) Au films sputtered onto polyethyleneterephthalate (PET). Sputtered Au film shows significantly different... more
ABSTRACT AFM, XRD, zeta (ζ) potential measurement and spectroscopic ellipsometry were used for characterization of thin (20nm) Au films sputtered onto polyethyleneterephthalate (PET). Sputtered Au film shows significantly different surface morphology and roughness in comparison with pristine PET. From XRD measurement of 20nm thick sputtered Au layers it was found that Au crystalizes preferentially in (111) direction with lattice parameter of a=0.40769nm, density of ρ=19.338gcm−3 and lattice stress of about 230MPa. Higher surface conductance of Au/PET by ζ-potential measurement was found. Au layer thickness of 19.4nm determined from spectroscopic ellipsometry was in good agreement with the AFM estimated value of 20nm.
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ABSTRACT Magnetotransport and magneto-optical (MO) results on sputtered Co/Au multilayers at 300 K are reported. The thickness of Co layer was fixed at tCo=1 nm while that of Au, tAu, varied between 2.2 and 4 nm. Two... more
ABSTRACT Magnetotransport and magneto-optical (MO) results on sputtered Co/Au multilayers at 300 K are reported. The thickness of Co layer was fixed at tCo=1 nm while that of Au, tAu, varied between 2.2 and 4 nm. Two giant-magnetoresistance (GMR) maxima were observed for tAu~2.4 and 3.9 nm. For tAu~2.4 nm the coercive field and switching fields are 7 and +/-30 Oe, respectively. MO Kerr hysteresis loops and spectra were measured in polar and longitudinal configurations. The loops provide evidence for the exchange coupling at the first GMR maximum and interface magnetic anisotropy for tAu
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ABSTRACT Sputtered Co/Cu multilayers were studied by means of magneto-optical (MO) Kerr spectroscopy. Remarkable changes in the MO spectra were observed for the multilayers where antiferromagnetic coupling take place. This may indicate... more
ABSTRACT Sputtered Co/Cu multilayers were studied by means of magneto-optical (MO) Kerr spectroscopy. Remarkable changes in the MO spectra were observed for the multilayers where antiferromagnetic coupling take place. This may indicate the changes in the electronic properties of Cu layers. The optical nature of this MO behaviour was verified by ellipsometric measurements.
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ABSTRACT Specular-mode spectroscopic ellipsometry is applied to analyze the optical response of gratings fabricated on a thick transparent plate substrate. The principles of the optical response of the gratings are described by employing... more
ABSTRACT Specular-mode spectroscopic ellipsometry is applied to analyze the optical response of gratings fabricated on a thick transparent plate substrate. The principles of the optical response of the gratings are described by employing incoherent contributions due to backreflections in the finite transparent substrate medium. A special function identifies a “diminution effect” caused by deflecting the secondary contributions from the primary beam axis. Two different methods are used to measure the ellipsometric response, a liquid solution method with the backreflections eliminated and a method including the incoherent backreflections. The grating parameters deduced by fitting from the measurement using the first method are applied to simulate the ellipsometric response using the second method. The spectral dependencies yielded by both methods are compared with remarkable agreement between the simulations and the measurements, which suggests the high usability of the backreflection method in the metrological characterization of gratings made on transparent plates.
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ABSTRACT Magneto-optical (MO) spectroscopy combined with spectroscopic ellipsometry has been used to learn about the electronic transitions in La2/3Sr1/3MnO3 (LSMO) film pulse laser deposited onto SrTiO3 (100) substrates. The dispersion... more
ABSTRACT Magneto-optical (MO) spectroscopy combined with spectroscopic ellipsometry has been used to learn about the electronic transitions in La2/3Sr1/3MnO3 (LSMO) film pulse laser deposited onto SrTiO3 (100) substrates. The dispersion function of LSMO films was parametrized by the sum of three damped Lorentz oscillators and adjusted together with the film thickness numerically. With the knowledge of film optical properties the off-diagonal elements of the LSMO permittivity tensor (magneto-optical constants) were calculated from the complex polar Kerr effect measured on the thickest (60 nm) LSMO film (considered as optically thick). The considered approximation as well as the reliability of the obtained optical and MO constants was verified by the consistence of the calculated and experimental MO spectra for the thinner LSMO films (where the propagation effect plays an important role). The resolved electronic transition centered at about 4 eV features the spectral dependences of diagonal and off-diagonal elements of LSMO permittivity in the studied spectral range. In the molecular orbital picture this could be assigned to the charge transfer electronic transition from the O 2p states to the Mn 3d t2g states, split by the spin-orbit interaction.
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ABSTRACT This study was aimed at deposition of self-assembled monolayers (SAMs) using vinyltriethoxysilane (VTES) and vinyltrichlorosilane (VTCS) molecules chemisorbed on silicon dioxide surfaces. The kinetics of SAM formation on planar... more
ABSTRACT This study was aimed at deposition of self-assembled monolayers (SAMs) using vinyltriethoxysilane (VTES) and vinyltrichlorosilane (VTCS) molecules chemisorbed on silicon dioxide surfaces. The kinetics of SAM formation on planar glass substrates and silicon wafers was characterized by contact angle measurements. The surface free energy and its dispersion and polar components enabled to estimate the time of immersion required to deposit compact SAMs. Adsorption of organosilane molecules as a function of immersion time was characterized by X-ray photoelectron spectroscopy. The SAM thickness was evaluated by spectroscopic ellipsometry. Surface topography of deposited layers was investigated by atomic force microscopy (AFM). The VTCS/glass combination exhibited the fastest kinetics but the deposit was not uniform and included local agglomerates. The hydrophobic vinyl groups at deposit surface resulted in a surface free energy of 32 mJ/m.
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The analytical formalism of Rokushima and Yamakita [J. Opt. Soc. Am. 73, 901–908 (1983)] treating the Fraunhofer diffraction in planar multilayered anisotropic gratings proved to be a useful introduction to new fundamental and practical... more
The analytical formalism of Rokushima and Yamakita [J. Opt. Soc. Am. 73, 901–908 (1983)] treating the Fraunhofer diffraction in planar multilayered anisotropic gratings proved to be a useful introduction to new fundamental and practical situations encountered in laterally structured periodic (both isotropic and anisotropic) multilayer media. These are employed in the spectroscopic ellipsometry for modeling surface roughness and in-depth profiles,
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ABSTRACT Spectroscopic ellipsometry (SE) with microscopic measurement spot is applied to extract geometrical parameters of a bi-periodic array of holes patterned on the top of an Si wafer, namely the holes' diameter and depth,... more
ABSTRACT Spectroscopic ellipsometry (SE) with microscopic measurement spot is applied to extract geometrical parameters of a bi-periodic array of holes patterned on the top of an Si wafer, namely the holes' diameter and depth, while the period of the patterning is assumed same as the value intended by the manufacturer. The SE response of the structure is simulated by the rigorous coupled-wave analysis implemented as the Airy-like internal reflection series, whose detailed description for the case of 2D gratings is provided with a brief demonstration of its convergence properties. The result of the extraction by SE is compared with results obtained by scanning electron microscopy (SEM) with reasonable agreement. The difference between some of the SE, SEM, and nominal parameters are discussed and the possibility to increase the accuracy of SE-based metrology is suggested.