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n this paper, we propose a new method for Bulk waves detection of an acoustic microwave signal during the propagation of acoustic microwaves in a piezoelectric substrate (Lithium Niobate LiNbO₃). 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 in order to build a model from which we note the Bulk waves easily. These singularities inform us of presence of Bulk waves in piezoelectric materials.

By which we obtain accurate values for each of the coefficient attenuation and acoustic velocity for Bulk waves. This study will be very interesting in modeling and realization of acoustic microwaves devices (ultrasound) based on the propagation of acoustic microwaves.

Our work is mainly about detecting 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.

Zn(1–x)MgxO thin films with various concentrations of magnesium were deposited using the spray pyrolysis method. The transmittance spectra recorded for all films exhibit maxima exceeding 90%. The band gap energy of the films with wurtzite structure increases from 3.22 up to 3.60 eV by incorporating Mg into ZnO. However, when the atomic ratio of Mg exceeded 0.4, a second crystalline phase (assigned to cubic MgO) became discernable in XRD patterns, a compressive strain was observed in the wurtzite lattice, and crystallite sizes decreased significantly. In accordance with these observations, finer grains with a pronounced columnar growth were observed in 3D AFM representations and the surface roughness decreases significantly. Finally, selective etching in water yields to porous films with a great surface-to-volume ratio, a lower refractive index and a better light transmission. These porous films with tunable band gap seem to be excellent candidates to various interesting applications.

: In the present work, thin films of Cr/NiO/Ni are deposited on glass substrates using RF magnetron sputtering technique. The uniformity and homogeneity of the prepared films were controlled by varying the power of the source, the targetsubstrate distance and the pressure of the plasma gas which is argon. In order to test the Preisach Model, we carried out measurements according to two directions: parallel and perpendicular to the substrate plane using a Vibrating Sample Magnetometer at room temperature. Good agreement has been obtained by comparing the experimental hysteresis loops to the ones determined using Preisach model. We conclude that this model is powerful in predicting the magnetic properties of multilayer systems.

In the last few years, an accelerated trend toward the miniaturization of nanoscale circuits has been recorded. In fact, this has been reflected by numerous enhancements at different levels of multi‐gate structures such as the channel body or the gate material. Our aim in this work is to investigate the reliability performance of junctionless DG MOSFET including graded channel aspect. The behavior of the considered device is analyzed numerically using ATLAS‐2D simulator, where degradation phenomena are accounted for in the model. The variation of some analog/RF criteria namely the transconductance and cut‐off frequency are established in terms of the channel length and traps density. The obtained responses indicate the superior immunity of the graded channel device against traps‐induced degradation in comparison to the conventional structure. Thus, this work can offer more insights regarding the benefit of adopting the channel doping engineering for future nanoscale electronic applications.

In this paper, a new particle swarm optimization‐based approach is proposed for the geometrical optimization of the nanowires solar cells to achieve improved optical performance. The proposed hybrid approach combines the 3‐D numerical analysis using accurate solutions of Maxwell's equations and metaheuristic investigation to boost the solar cell total absorbance efficiency. Our purpose resides on modulating the electric field and increasing the light trapping capability by optimizing the radial solar cell geometrical parameters. Moreover, a comprehensive study of vertical core‐shell nanowire arrays optical parameters such as the integral absorption, reflection, and total absorbance efficiency is carried out, in order to reveal the optimized radial solar cells optical performance for low‐cost photovoltaic applications. We find that the proposed hybrid approach plays a crucial role in improving the nanowires solar cells optical performance, where the optimized design exhibits superior total absorbance efficiency and lower total reflection in comparison with those provided by the conventional planar design. The obtained results make the proposed global optimization approach valuable for providing high‐efficiency nanowires solar cells.

Bilayer of nickel and nickel oxide were deposited on glass substrates using RF magnetron sputtering technique. The magnetic properties of the prepared thin films were carried out at room temperature in both parallel and perpendicular magnetic field to the sample. The Preisach model was applied to provide a mathematical model of the magnetic hysteresis loop in the case of parallel geometry, along the easy axis of the bi-layer NiO / Ni. Good agreement was obtained between the theoretical and experimental results.

Tin oxide SnO₂ thin films were deposited by sol gel method on glass substrates. The as-deposited thin films were then annealed at 550 °C for different time durations (15, 30, 60 and 120 min). Structural and morphological investigations were carried out on all samples by X-ray diffraction method and atomic force microscopy while optical properties were obtained with UV–Visible spectrophotometer. XRD patterns reveals that the samples possess polycrystalline with rutile structure of SnO₂ without any secondary phase. AFM image showed that SnO₂ thin films having a smooth surface morphology. The optical properties in the visible range showed that the deposited layers have a high transmission factor. The optical band gap energy varies in the range of 3.61–3.73 eV. Finally, ultraviolet (UV) detection properties of samples as an active layer in UV photodetector devices were investigated. Current-voltage characteristics of the SnO₂ thin films are performed under dark and light environment, which show low dark current of 22.9 nA with a linear behavior and high current ration > 10⁴ under 2 V applied voltage and 120 min as annealing time. Whereas, high photocurrent is observed for samples annealing for 30 min. Moreover, the transient photoresponse of the fabricated device is reported under different annealing times.

In this paper, a new design methodology by optimizing the silicon/organic interface morphology is proposed to achieve superior optical behavior for pentacene-based organic/inorganic solar cells. Our purpose dwells on reducing the refracting light in the silicon and improves the absorbance behavior in the solar cell. In this context, a numerical model based on accurate solutions of Maxwell’s equations is developed in order to study the impact of both interface texturization morphologies (triangular and grooves) on the optical absorbance and electrical performance. It is found that the proposed design morphology has profound implication on modulating the electric field, which increases the light trapping capability. It is also confirmed that the overall electrical performance is significantly improved as compared to the conventional organic/inorganic solar cells, where the proposed design exhibits superior integral absorption behavior and large interface area. Moreover, a new hybrid approach by combining of the numerical and metaheuristic models is developed to boost the device performance by optimizing the interface morphology. The obtained results make the proposed design methodology valuable for providing high-efficiency organic/inorganic solar cells.

In this paper, graded channel doping (GCD) and junctionless paradigms are proposed as a new ways to improve the optical controlled field effect transistor (OCFET) and bridging the gap between the high responsivity and ultra-low power consumption. A careful mechanism study based on numerical investigation and a performance comparison between the proposed structure and both the conventional inversion mode (IM-OCFET) and the junctionless (JL-OCFET) designs is presented. It is found that the graded channel doping feature can efficiently improve the overall device optical and electrical performances. Moreover, the proposed design exhibits superior device figures of merit (FoMs) and provides ultra-sensitivity behavior as compared to both the conventional IM-OCFET and the JL-OCFET counterparts. Our investigation reveals also the outstanding capability of the proposed structure for offering the weak signal detection advantage that demonstrates the unique property of our phototransistor with GCD aspect. These characteristics not only underline the excellent switching behavior of the proposed design but also demonstrate the ability for overcoming the trade-off between the low cost and readily fabrication process in addition to ultrasensitive aspect with low power consumption. This makes the proposed GCD-JL-OCFET a potential alternative for developing low power communication systems.

In this paper, a new junctionless optical controlled field effect transistor (JL-OCFET) and its comprehensive theoretical model is proposed to achieve high optical performance and low cost fabrication process. Exhaustive study of the device characteristics and comparison between the proposed junctionless design and the conventional inversion mode structure (IM-OCFET) for similar dimensions are performed. Our investigation reveals that the proposed design exhibits an outstanding capability to be an alternative to the IM-OCFET due to the high performance and the weak signal detection benefit offered by this design. Moreover, the developed analytical expressions are exploited to formulate the objective functions to optimize the device performance using Genetic Algorithms (GAs) approach. The optimized JL-OCFET not only demonstrates good performance in terms of derived drain current and responsivity, but also exhibits superior signal to noise ratio, low power consumption, high-sensitivity, high I_ON/I_OFF ratio and high-detectivity as compared to the conventional IM-OCFET counterpart. These characteristics make the optimized JL-OCFET potentially suitable for developing low cost and ultrasensitive photodetectors for high-performance and low cost inter-chips data communication applications.

In this paper, a new metallic thin film engineering aspect is proposed to achieve superior absorption for TiO₂/Metal/TiO₂ on Silicon substrate UV-based photodetectors (PDs). The overall device optical performance comparison with three dissimilar metallic layers (Au, Ti, and Ag) is performed numerically using accurate solutions of Maxwell׳s equations. A comprehensive study of the device optical parameters such as the integral absorption, reflection, and rejection ratio is carried out, in order to reveal the device optical performance for UV optical interconnects and environment monitoring applications. We find that the optical performance are considerably improved as compared to the conventional design, where the proposed design offers superior integral absorption and lower total reflection with an acceptable rejection ratio in comparison with those provided by the conventional one. These improvements suggest the opportunity for optimizing the proposed design using particle swarm optimization (PSO) approach for achieving higher optical performance, where excellent capability is recorded in enhancing the device optical behavior. The obtained results make the prop sed device very efficient for compatible CMOS modern technology.

In this paper, new multilayer design based on ZnO/Ag/ZnO structure is proposed as a new way to achieve UV-based photodetector (PD) with superior optical behavior. Our purpose resides on reducing the refracting light and achieving an effective absorption in the Ag metallic sub-layers. New numerical model based on accurate solutions of Maxwell’s equations is developed in order to elucidate the impact of the metallic sub-layers on the UV-PD optical performance. An overall analysis regarding the optical parameters such as the integral absorption and the total reflection is conducted. It is found that the metallic sub-layers have profound implications on modulating the electric field in the structure and facilitating photon forward scattering in the ZnO sub-layers which led to better optical behavior. Moreover, Particle Swarm Optimization (PSO) approach is proposed as a metaheuristic technique to reach effectiveness absorption through carefully adjusting the Ag and ZnO sub-layers thickness. It is confirmed that the optimized design can provide superior optical performance as compared to the conventional counterpart, where the optimized multilayer design exhibits an enhancement of 60% in the integral absorption over ZnO-based PD. The obtained results make the proposed multilayer design efficient for providing high performance PDs for communication applications.