In this work, thin films of aluminum doped ZnO (AZO) were deposited on ultrasonically cleaned glass substrates by sol-gel process using dip and spin coating techniques. For this purpose, Zinc acetate dihydrate, aluminum nitrate nonahydrate, ethanol and mono ethanolamine were employed as precursor, dopant, solvent and stabilizer, respectively. X-ray diffraction, UV–vis, photoluminescence, 4-point probe and Van der pauw techniques were investigated for the characterization of the prepared AZO thin films. X-ray-analysis revealed that all the prepared films have hexagonal wurtzite structure with a relative preferential orientation along the c-axis and the lattice parameters are close to the standard values reported in literature. UV–vis spectroscopy showed that the average value of the films’ transmittance in the visible region is found to be around 85% and the gap ranges in the interval [3.15 eV–3.30 eV]. The photoluminescence spectrum only showed the UV peak while the broad band of the visible region was completely vanished. The electrical measurements indicate that sol-gel methods provide relatively high resistivities compared to those obtained with physical vapor deposition (PVD) techniques.

In this paper, Ni/NiO/Ni multilayers are deposited on glass substrates using radio frequency magnetron sputtering, where the structural and morphological properties are analyzed using X-ray diffraction besides scanning electron microscopy techniques. The associated magnetic hysteresis loops are obtained by vibrating sample magnetometer for temperatures ranging from − 100 to 300 °C. Hence, the parameters α, β, Bmax, HC, and Br defining a hysteresis loop are determined at each temperature using Preisach model for the first two parameters, while the remaining ones are deduced experimentally. The set of these parameters are introduced within the training data set in the context of an ANFIS-based approach to predict the hysteresis loop of a Ni/NiO/Ni multilayer for any temperature below the Curie temperature. The comparison conducted between theoretical and experimental results showed a good agreement. This work provided more insights regarding the consolidation of experimental characterization with the development of soft computing-based frameworks.

The effect of the presence of electron–phonon (e–ph) coupling in the SiC, GeC and SnC hybrids is studied in the framework of the ab initio perturbation theory. The electronic bang gap thermal dependence reveals a normal monotonic decrease in the SiC and GeC semiconductors, whereas SnC exhibits an anomalous behavior. The electron line widths were evaluated and the contributions of acoustic and optical phonon modes to the imaginary part of the self-energy were determined. It has been found that the e–ph scattering rates are globally controlled by the out-of-plane acoustic transverse mode ZA in SiC while both ZA and ZO are overriding in GeC. In SnC, the out-of-plane transverse optical mode ZO is the most dominant. The relaxation lifetime of the photo-excited electrons shows that the thermalization of the hot carrier occurs at 90 fs, 100 fs and 120 fs in SiC, GeC and SnC, respectively. The present study properly describes the subpicosecond time scale after sunlight illumination using an approach that requires no empirical data. The results make the investigated structures suitable for providing low cost and high-performance optical communication and monitoring applications using 2D materials.

In this paper, versatile Metal/TCO/p-Si Schottky Barrier Diodes (SBDs) with dissimilar TCO intermediate layers (ZnO and ITO) were fabricated by RF magnetron sputtering technique. An overall electrical performance comparison between the Al/ZnO/p-Si, Au/ITO/p-Si and the conventional Au/p-Si structures is carried out. The measured I-V characteristics indicate that the proposed Al/ZnO/p-Si design exhibits an outstanding capability for achieving a high rectifying ratio of 142 dB. This is mainly due to the enhanced Schottky barrier height (SBH) of 0.75 V and close to unite ideality factor (n = 1.23). Such behavior can be attributed to the enhanced interface quality achieved by introducing TCO inter-layers, which could decrease the Series resistance. A comparative study of the elaborated structures performance is carried out in which new Figures of Merit (FoM) parameters that combine both electrical and thermal stability performances are proposed. The Experimental results show that the proposed designs with ITO and ZnO sub-layers exhibits improved FoM parameters as compared to the conventional Au/p-Si structure. Moreover, this comparative study enables to the designer to acquire a comprehensive review about the Si-based SBDs design tradeoffs. It is demonstrated that the insertion of a TCO inter-layer might be beneficial for avoiding the degradation related-heating effects. Therefore, the proposed designs offer the possibility of bridging the gap between superior electrical performance and high thermal stability, which makes them suitable for developing high-performance Schottky solar cells and sensing applications.

This paper presents the optimization, elaboration and characterization of a new TCO (Transparent Conductive Oxides) electrode based on ITO/Ag/ITO multilayer design that enables overcoming the trade-off between the electrical and optical properties. A new hybrid approach combining the investigated design and Particle Swarm Optimization (PSO) technique is conducted with the aim of maximizing the Haacke Figures of merit (FoM). It is found that the optimized ITO/Ag/ITO tri-layered design paves a new path toward achieving a high FoM of 125 × 10⁻³Ω⁻¹. Such improvement is attributed to the improved light management achieved by the efficient modulation of the Ag sub-layer geometry. Subsequently, the optimized multilayer design is fabricated using RF magnetron sputtering technique. The structural, optical and electrical properties associated with the deposited ITO/Ag/ITO multilayer structure are also analyzed. It is found that the fabricated TCO-based electrode shows a high transmittance over than 94.1% and a low sheet resistance of 4.5Ω × sq⁻¹, which is in good agreement with the theoretical predictions. Therefore, the proposed design methodology based on experiments assisted by PSO metaheuristic approach offers exciting opportunities for bridging the gap between transparency and conductivity characteristics. This makes the elaborated ITO/Ag/ITO multilayer design suitable for high-performance optoelectronic applications.

In this paper, a new Au/p-Si Schottky Barrier Diode (SBD) based on Indium Tin Oxide (ITO) intermediate thin-film is proposed and experimentally investigated by including the annealing temperature effect. We elaborated the Au/ITO/p-Si structure by means of RF magnetron sputtering technique and compared its electrical properties with the conventional Au/p-Si SBD. The role of the annealing process at 200 and 400 °C as well as the ITO interface thin-layer in improving the SBD basic electrical parameters is analyzed. The characterization has revealed that a higher Schottky barrier (ϕ_b) of 0.79V is achieved. Moreover, close to unit ideality factor of (n = 1.25) and reduced density of states (N_ss = 1.5 × 10¹²cm⁻²) and series resistance of (R_s = 32Ω) are recorded. These achievements can be attributed to the enhanced interface quality provided by introducing the ITO thin-film. Moreover, the annealing process enables improved crystallinity and allows efficient rearrangement of atoms at the interfaces. The thermal stability behavior of the investigated designs is analyzed, where new Figure of Merit (FoMs) parameters are proposed. It is found that the annealed Au/ITO/p-Si structure offers the opportunity for suppressing the degradation related-heating effects. Therefore, the proposed Au/ITO/p-Si SBD pinpoint a new path toward achieving superior electrical characteristics and improved thermal stability, which makes it a potential alternative for high-performance microelectronic and optoelectronic applications.

In this paper, a new Se/CZTSSe tandem solar cell architecture is proposed as a viable approach to reach ultrahigh efficiency values at low fabrication cost. The proposed tandem design consists of a Se-based top cell with Ti intermediate ultra-thin metallic layers (MLs) and a CZTS bottom cell with graded band-gap aspect. The role of the introduced design amendments in achieving the dual-benefit of enhanced optical behavior and reduced recombination losses is investigated by means of an accurate numerical modeling. Moreover, a comprehensive study which involves the impact of design parameters such as the MLs position and the CZTSSe band-gap profile on the device performance is carried out. Moreover, Particle Swarm Optimization (PSO)-based metaheuristic technique is used to boost up the Se/CZTSSe tandem cell efficiency by identifying both the suitable position of the introduced ultrathin MLs and the appropriate CZTSSe band-gap profile. It is found that the adopted optimization approach pinpoints a new path toward achieving over 30% efficiency, not only it provides the possibility to reduce interface recombination effects by optimizing the band offset at the buffer/absorber interfaces but also enables selecting the most favorable design configuration associated with enhanced optical behavior. This makes the optimized Se/CZTSSe tandem solar cell potential alternative for providing high-efficiency and stable tandem solar cell.

In this paper, a transparent conductive ITO/Ag/ITO (IAI) multilayer structure with a high Haacke Figure of Merit (FoM) far surpassing those found up to now is experimentally demonstrated. An optimized IAI multilayer electrode was elaborated by means of RF magnetron sputtering technique. The structural and electrical characteristics of the prepared tri-layered design were investigated. The influence of the annealing process on the IAI electrode performance was also carried out. Unlike the IAI structure as-deposited, it was revealed that the annealed samples maintained an average transparency superior than 89%. This behavior indicates the effectiveness of the thermal treatment for ensuring favorable light management. In addition, it was found that the annealing process paves a new path toward improving the electrode conductivity, where the heat treated electrode at 600°C yielded a very low sheet resistance of 2.95Ω × sq⁻¹. Therefore, by well optimizing both IAI geometry and annealing conditions, we were able to elaborate high-quality coating with a superior FoM of 120.8 × 10⁻³Ω⁻¹. This makes the sputtered IAI multilayer design a suitable alternative to the conventional ITO-based electrodes for optoelectronic and photovoltaic applications.

This paper presents an efficient method for recovery of SIMS signals from strongly noised blurred discrete data. This technique is based on Tikhonov-Miller regularization where a priori model of solution is included. The latter is a denoisy signal obtained using the Kalman filter. This is an interesting estimation method, but it can only be used when the system is described precisely. By comparing the results of the proposed technique with those of the literature, our algorithm gives the best results without artifacts and oscillations related to noise and significant improvement of the depth resolution. While, the gain in FWHM is less improved than those obtained by the wavelet technique. Therefore, this new algorithm can push the limits of SIMS measurements towards its ultimate resolution.

In this paper, we propose a new numerical method for acoustics microwaves detection of an acoustics microwaves signal during the propagation of acoustics microwaves in a piezoelectric substrate zinc oxide (ZnO). We have used support vector machines (SVMs), the originality of this method is the accurate values that provides this technique help to identify undetectable waves that we can not identify with the classical methods. We classify all the values of the real part and the imaginary part of the coefficient attenuation with the acoustic velocity in order to build a model from which we note the types of microwaves acoustics (bulk waves or surface waves or leaky waves). We obtain accurate values for each of the coefficient attenuation and acoustic velocity. This study will be very interesting in modelling and realisation of acoustics microwaves devices (ultrasound, radiating structures, filter SAW…) based on the propagation of acoustics microwaves.

Our work is mainly about detecting acoustics microwaves in the type of BAW (Bulk acoustic waves), where we compared between Lithium Niobate (LiNbO3) and Lithium Tantalate (LiTaO3) ,during the propagation of acoustic microwaves in a piezoelectric substrate. In this paper, We have used the classification by Probabilistic Neural Network (PNN) as a means of numerical analysis in which we classify all the values of the real part and the imaginary part of the coefficient attenuation with the acoustic velocity for conclude whichever is the best in utilization for generating bulk acoustic waves.This study will be very interesting in modeling and realization of acoustic microwaves devices (ultrasound) based on the propagation of acoustic microwaves.

In this paper, we present a rigorous full-wave analysis able to estimate exactly the resonant characteristics of stacked high T_c superconducting circular disk microstrip antenna. The superconducting patches are assumed to be embedded in a multilayered substrate containing isotropic and/or uniaxial anisotropic materials (the analysis is valid for an arbitrary number of layers). London’s equations and the two-fluid model of Gorter and Casimir are used in the calculation of the complex surface impedance of the superconducting circular disks. Numerical results are presented for a single layer structure as well as for two stacked circular disks fabricated on a double-layered substrate.

The resonant frequencies and bandwidths of the inverted rectangular patch over anisotropic substrates are investigated in this paper. A rigorous analysis is performed using dyadic Green’s function formulation in the vector Fourier transform domain. The Galerkin’s technic is then used in the resolution of the integral equation; the complex resonance frequencies for the TM01 mode are studied with sinusoidal basis functions. The numerical results obtained are compared with previously published numerical results computed by means of the electromagnetic simulator “IE3D software”. Good agreement is found in all cases among all sets of results. For an isotropic substrate, it is confirmed that the bandwidth decreases with increasing of air-gap layer for high permittivity and low thickness of the substrate. Also, we show that the resonant frequencies and bandwidths are highly dependent on the permittivity variations alongside the optical axis. Other theoretical results attained display that the resonant frequencies downtrend monotonically with increasing substrate thickness, the diminution being larger for the uniaxial anisotropy of the substrate. Finally, numerical results for the effects of uniaxial anisotropy in the substrate on the radiation of the inverted rectangular microstrip structure are also presented.

Electronic Nose, as an artificial olfaction system, has potential applications in environmental monitoring because of its proven ability to recognize and discriminate between a variety of different gases and odors. In this paper, we used a chemical sensor array to develop an electronic nose to detect and identify seven different gases (H₂, C₂H₂, CH₄, CH₃OCH₃, CO, NO₂, and NH₃). These gas sensors are chosen because of its hierarchical/doped nanostructure characteristics, which give them a very high sensitivity and low response time; we improve the linearity response and temperature dependence using models based on artificial neural networks. We used in Electronic nose a pattern recognition based on artificial neural network, which discriminates qualitatively and quantitatively seven gases and has a fast response.