Papers by Nadia Benseddik
Experimental and Theoretical NANOTECHNOLOGY
The GaAsN alloy has a great potential in the manufacture of the photovoltaic devices. A simple op... more The GaAsN alloy has a great potential in the manufacture of the photovoltaic devices. A simple optimized GaAsN junction can reach conversion efficiency from > 20%, comparable with that reached by the best cells of die CISGS. Because the band gap of GaAsN can be modified from 1.4 eV to 3.4 eV by increasing the nitrogen content with multi-junction cells, it is theoretically possible to achieve the record performance 70% with this only material system, whereas the theoretical record in technology GaAs multi-junctions is less than 50%. The work presented in this paper concerns the study of photovoltaic cells based on GaAsN nitrided materials. The main objective is to optimize the front and base with their thickness and doping, on the electrical characteristic of the photovoltaic cell and subsequently its output parameters under solar illumination of AM1.5G. 54.1 % efficiency is predicted for this new GaAs1-xNx based on a simple single solar cell. This structure can also provide a fu...
Advances in Materials and Processing Technologies, 2020
The ternary (ABX2) semiconductors have wide optical band gaps range and motilities of carrier, ha... more The ternary (ABX2) semiconductors have wide optical band gaps range and motilities of carrier, has led to their appearance importance device materials, including solar cells of photovoltaic and light-emitting diodes. In accordance with this, AgInTe 2 solar cells have proved to be the next big advancement in the field of solar energy. In this work, different numerical simulations were performed using SCAPS. The doping density and layer thickness are investigated under solar illumination of AM1.5 for optimised performance of solar cell. Thus, starting from J-V curves, we have calculated the short-circuit current density J sc , the open-circuit voltage V oc , the fill factor and the efficiency conversion. This structure can also provide a fundamental solar cell unit for developing very high efficiency solar cell.
physica status solidi (a), 2021
The advantage of the high versatility of the nanocomposite (Nc) materials in modeling photonic st... more The advantage of the high versatility of the nanocomposite (Nc) materials in modeling photonic structure devices is exploited to design an optical biosensor based on Bloch surface waves (BSWs) to probe different biomolecular species. The suggested biosensor is constituted by two periods of low and high refractive indices (RIs) of alternate dielectric materials SiO2 and TiO2 capped by Ag−TiO2 Nc layer operating under the Kretschmann configuration and using p‐polarized incident light. Herein, the biosensor performances are theoretically investigated in a wide range of the sensing medium RI [1.33, 1.61] using selected operating wavelengths 455, 465, 480, 500, and 600 nm to deviate a large dielectric loss of the Ag−TiO2 Nc layer. The results show that the structure sustains BSW for each wavelength in separate domains of the sensing medium RI conferring to the proposed biosensor a potential for the high‐sensitive multiwavelength detection of different biomolecular entities.
Journal of Optoelectronics and Advanced Materials
ABSTRACT
International Journal of Metals, 2014
The structural and electronic properties of the ternaryCd1-xBexSealloys have been calculated usin... more The structural and electronic properties of the ternaryCd1-xBexSealloys have been calculated using the full-potential linear muffin-tin-orbital (FP-LMTO) method based on density functional theory within local density approximation (LDA). The calculated equilibrium lattice constants and bulk moduli are compared with previous results. The concentration dependence of the electronic band structure and the direct and indirect band gaps are investigated. Moreover, the refractive index and the optical dielectric constant forCd1-xBexSeare studied. The thermodynamic stability of the alloys of interest is investigated by means of the miscibility. This is the first quantitative theoretical prediction to investigate the effective masses, optical and thermodynamic properties forCd1-xBexSealloy, and still awaits experimental.
International Journal of Materials Engineering Innovation, 2014
We present in this article current-voltage I(V) and capacitance-voltage C(V) characteristics of S... more We present in this article current-voltage I(V) and capacitance-voltage C(V) characteristics of Schottky diodes based on SiC. These diodes have different surfaces of Schottky contact. The effect of the surface on the behaviour of the diode is studied. Different current transport mechanisms are revealed from measurements. In addition to thermionic current, other currents are added like the recombination current, tunnelling current and leakage current. Different parameters are extracted from I(V) and C(V) characteristics, such as ideality factor, barrier height, series resistance, doping and the density of interface states.
Sensor Letters, 2009
ABSTRACT In this report we talk about the electrical conduction of 4H-SiC Schottky diodes. The co... more ABSTRACT In this report we talk about the electrical conduction of 4H-SiC Schottky diodes. The contribution of thermionic-emission current and various other current transport mechanisms were assumed when evaluating the Schottky barrier height. Thus the generation-recombination, tunneling and leak currents caused by inhomogeneities and defects at metal–semiconductor interface were taken into account. Schottky barrier height determined from the I(V) measurement is close to 1.17 eV, ideality factor 1.4 and series resistance 1.5 Ω at 300 K.
Sensor Letters, 2009
ABSTRACT In the present paper, the influence of thermal processing in forming gas on the MOSP str... more ABSTRACT In the present paper, the influence of thermal processing in forming gas on the MOSP structure is investigated by the high frequency capacitance-voltage technique. We have characterised two MOSP structures. The characteristics are obtained forward and after annealing. Annealing of the MOSP structures results in an increase of the slope of the C(V) curve in the depletion region and in a shift of the curve along the voltage axis towards positive voltage values. The interface states have a very significant role in the components containing MOS structures. In this paper, we study the interface states densities effect on Metal/oxide/polysilicon capacitance. The effective density of interface charges (QT has been calculated by evaluating the flat band voltage (VFB of the C(V) curves. The |QT| and |VFB| values decrease when the samples are annealed at 400 °C. The quality of structure MOSP will be improved.
Sensor Letters, 2011
ABSTRACT Metal-organic chemical vapour deposition-grown fieldplated 0.25 μm gate-length AlGaN/GaN... more ABSTRACT Metal-organic chemical vapour deposition-grown fieldplated 0.25 μm gate-length AlGaN/GaN high-electron mobility transistors (HEMTs) with field-plate lengths of 0.5 μm over dielectric passivation layers have been fabricated on SiC substrates and characterized. These 0.25 μm gate-length devices exhibited maximum drain current density of more than 1.18 A/mm, peak extrinsic transconductance of 245 mS/mm, a lower gate leakage current density, and a higher breakdown voltage.
Sensor Letters, 2011
ABSTRACT This work presents the study of the effect of a thin gallium nitride (GaN) layer, deposi... more ABSTRACT This work presents the study of the effect of a thin gallium nitride (GaN) layer, deposited on GaAs substrate. Then, the electrical characterisations are realized using the I–V and C–V measurements. The plotted curves of Hg/δ-GaN/n-GaAs heterostructures, with various thicknesses δ of GaN films, are compared with the Hg/GaAs ones. The thickness of GaN (2.8 nm) deposited on GaAs followed by an annealing operation improves the conduction current. In fact, the (I–V) characteristics reveal a low series resistance (49 Ω) for the annealed sample compared with a value of 117 Ω obtained in the not annealed ones. Comparing the annealed samples, the significant value of the ideality factor (n > 2.5) is obtained in the nitrided samples with large thickness of the GaN layer. This effect is probably due to the existence of a tunnel current. However, in the sample with a lower thickness (1.8 nm) presents an interessant ideality factor (1.3). The (C–V) characteristics show that the annealing operation decreases the barrier height φbn (0.69–0.77 eV) for the annealed samples compared with (1.77–1.88 eV) obtained for the not annealed samples. The concentration doping of the samples which have a sufficiently thickness of GaN layer is higher than concentration of GaAs substrate. This effect is probably due to the presence of nitrogen vacancies which are known to act as levels donors in the GaN layer. The value of the interface state density N ss at mid-gap is about 3 × 1011 eV−1 cm−2 for the nitridated samples showed in Figure 3.
The current-voltage (I-V) and capacitance voltage (C-V) characteristics of Al/n- GaAs and Al/p-Ga... more The current-voltage (I-V) and capacitance voltage (C-V) characteristics of Al/n- GaAs and Al/p-GaAs diodes on GaAs substrate treated by Ru 3+ ions are investigated and compared with characteristics of GaAs diodes on GaAs untreated substrates. The diodes does not have to show an ideal behaviour of I-V characteristic with an ideality factor of 1.13 and barrier height of 0.85 eV and 0.6 eV for Al/n-GaAs and Al/p-GaAs diodes respectively. The forward bias saturation current found with a big value (10 -10 A, 10 -12 A) in the Al/n-GaAs (untreated) Schottky diodes compared with Al/n-GaAs (treated) diodes. Contrary the forward bias saturation current found with a small value (10 -7 A, 10 -6 A) in the Al/p-GaAs (untreated) Schottky diodes compared with Al/p-GaAs (treated) diodes. The energy distribution of interface states was determined from the forward bias I(V) characteristics. The interface states density found large in the Al/GaAs (treated by Ru 3+
Optical and Quantum Electronics, 2013
In this paper, we have studied the Schottky contact of two structures AlInN/GaN and AlGaN/GaN in ... more In this paper, we have studied the Schottky contact of two structures AlInN/GaN and AlGaN/GaN in transistors HEMTs. The current-voltage Igs(Vgs) of AlInN/GaN and AlGaN/GaN structures were investigated at room temperature. The electrical parameters such as ideality factor (2.3 and 1.96), barrier height (0.72 and 0.71 eV) and series resistance (33 and 153) were evaluated from I-V data. The comparison of the performance of the two structures AlInN/GaN and AlGaN/GaN in transistors HEMTs have been analyzed and discussed.
Computational Condensed Matter
International Journal of Materials Engineering Innovation, 2014
In this paper, electrical characterisation and analytical modelling of current-voltage (I-V) and ... more In this paper, electrical characterisation and analytical modelling of current-voltage (I-V) and capacitance-voltage (C-V) for Hg/InN/n-InP Schottky structures are investigated. We have studied electrically thin InN films realised by the nitridation of InP(100) substrates using a glow discharge source (GDS) in ultra high vacuum. So, we have calculated, using I-V and C-V measurements, the ideality factor n, the saturation current I s , the barrier height , bn φ the series resistance R s , the doping concentration N d and the diffusion voltage V d. We have also established analytical calculation programmes of I-V and C-V curves in order to show the effect of the interface layer InN and series resistance R s on the calculated parameters.
Optical and Quantum Electronics, 2013
In this paper, we developed a numerical calculation program, using Turbo Pascal, to determine the... more In this paper, we developed a numerical calculation program, using Turbo Pascal, to determine the current-voltage characteristics of a N + P solar cells in order to find the main parameters influencing the conversion efficiency. We adopted a one-dimensional numerical model for the resolution of the three semiconductor equations, which are: the Poisson's equation and the two continuity equations of electrons and holes. Our system of equations is written in term of ϕ, ϕ n , and ϕ p , and it's resolved using the finite difference method. This code enables us to draw the current density versus the voltage for different layer thicknesses, the conversion efficiency versus the minority carrier life time and the spectral response versus the wavelength. In order to compare the conversion efficiency of two different solar cells, we simulated a solar cell based on III-V nitride compounds (In x Ga 1−x N) and a monocrystalline silicon solar cell.
Materials Science and Engineering: B, 2005
A silver contact with polysilicon fabricated on glass substrates was investigated both experiment... more A silver contact with polysilicon fabricated on glass substrates was investigated both experimentally and theoretically by means of measured and 2D-simulated C-V characteristics. The in situ phosphorus-doped polysilicon layer is grown by a low-pressure chemical vapor deposition (LPCVD) technique and crystallized in a vacuum by thermal annealing. The measured C −2-V characteristics of the Schottky contact at two frequencies reveals a linear behaviour at the 10 kHz curve and a distinct non-linear behaviour at the 300 kHz one. Extraction of the frequency independent capacitance by the Kevin method allows the determination of the values of doping concentration (N D = 5 × 10 18 cm −3) and Schottky barrier height (φ b = 0.65 eV). The 2D-numerical simulation code of the Schottky contact C-V characteristics is also developed by considering that the inter-granular traps density N T is localized in the grain boundaries. The effects of the film doping concentration and the trap states density are investigated.
Materials Chemistry and Physics, 2009
... According to Heller, the basic solution of Se 2− /Se 2 2− after chemical and electrochemical ... more ... According to Heller, the basic solution of Se 2− /Se 2 2− after chemical and electrochemical reactions with the arsenic leads to the formation of complex (AsSe 3 3+ ), passes in solution, and adsorption of selenide on the surface of GaAs, which can explain the decrease in height ...
International …, 2009
Int. J. Nanoelectronics and Materials 2 No. 1 (2009) 75-89 ... 2D-Modelling for the simulation of... more Int. J. Nanoelectronics and Materials 2 No. 1 (2009) 75-89 ... 2D-Modelling for the simulation of current-voltage characteristics in polysilicon schottky diode deposited by LPCVD and SAPCVD methods. ... Nadia Benseddik1,*, Mohammed Amrani1, Zineb Benamara1, Tayeb ...
Experimental and Theoretical NANOTECHNOLOGY
The current–voltage (I–V) characteristics of Schottky diodes on free-standing GaN substrate are i... more The current–voltage (I–V) characteristics of Schottky diodes on free-standing GaN substrate are investigated by using electrical characterization and analytical modelling calculation. We have calculated the electrical parameters from experimental current-voltage curve by two methods: ln(I) and Cheung. So, we calculated different electrical parameters using experimental I-V curve such as saturation current, ideality factor, series resistance and barrier height. We have found from the first method, the ideality factor n (1.02), the barrier height fb (0.65 eV) and a series resistance Rs (84 Ω). From the second method, we have found, n (1.09), fb (0.79 eV) and Rs (79.58 Ω - 79.73 Ω). Using analytical approach, we plotted the theoretical curves for comparison with the experimental characteristic and also to determine the dominant current transport mechanism. The results found support an assumption that the dominant current mechanism in Au/n-GaN (free-standing substrate) Schottky diode is...
Journal of Alloys and Compounds, 2010
The structural, electronic and optical properties of InxGa1−xAs, GaAs1−yPy ternary and InxGa1−xAs... more The structural, electronic and optical properties of InxGa1−xAs, GaAs1−yPy ternary and InxGa1−xAs1−yPy quaternary semiconductor alloys are investigated using firstprinciples plane-wave pseudo-potential method within the LDA approximations. For these alloys lattice parameters, bulk modulus, band gap energy and density of states are calculated. Besides, we have calculated the optical parameters (dielectric functions, energy loss function, reflectivity, absorption and refractive index) of these semiconductor alloys. Our results agree well with the available theoretical and experimental data in the literature.
Uploads
Papers by Nadia Benseddik