DEHIMI LAKHDAR - Academia.edu (original) (raw)
Papers by DEHIMI LAKHDAR
In this work, an analytical model is used to describe the elctrical characteristics of a dual-jun... more In this work, an analytical model is used to describe the elctrical characteristics of a dual-junction tandem solar cell performing a conversion efficiency of 32.56% under air mass 1.5 global (AM1.5G) spectrum. The tandem structure consists of a thin heterojunction top cell made of indium gallium phosphide (InGaP) on gallium arsenide (GaAs), mechanically stacked on a relatively thick germanium (Ge) substrate which acts as bottom cell. In order to obtain the best performance of such a structure, we simulate for both the upper and lower sub-cell the current density-voltage, power density-voltage, and spectral response behaviours taking into account the doping-dependent transport parameters and a wide range of minority carrier surface recombination velocities.For the proposed tandem cell, our calculations predict that optimal photovoltaic (PV) parameters, namely the short-circuit current density (Jsc), open-circuit voltage (Voc), maximum power density (Pmax), and fill factor (FF) are J...
La resistivite (ρ) d’une structure p + nn + au silicium, utilisee comme detecteur de particules t... more La resistivite (ρ) d’une structure p + nn + au silicium, utilisee comme detecteur de particules travaillant dans un environnement hostile et soumis a de fortes fluences, est simule numeriquement en utilisant la methode des differences finies. Lorsque cette jonction est soumise a des fortes radiations, des defauts structuraux sont crees qui ont des effets indesirables et peuvent degrader les performances des detecteurs. Ces defauts se manifestent comme des pieges accepteurs et des centres de generation-recombinaison (g-r). La resistivite augmente avec l’augmentation de la densite du piege accepteur pour atteindre la resistivite intrinseque (maximale).
In this work,theforward current-voltagecharacteristics of n-type Al implanted 4H-SiC pin diodesha... more In this work,theforward current-voltagecharacteristics of n-type Al implanted 4H-SiC pin diodeshave been investigated experimentally and by mean of numerical simulations in the 298-378K temperature range. Our simulations were performed using proprietary simulations software. The model parameters to be calibrated in the simulation are the electron and hole minority carriers lifetimes.The measured forward I-V characteristics showed two differentbehaviour, the leaky behaved and well behaved diode. The later diodes were considered for simulation comparison.Employing temperature-dependent carrier lifetimes as a fitting parameter, the simulation indicates that drift layer and bulk carrier lifetime ranging from 10ns to 50ns. We achieved a good agreement between simulations and measured data. The measured and the simulated forward characteristics indicate an ideality factor of about1.3for the region 2.5V-2.78Vand 2.14 in the low injection region. Activation energies of about 1.61eV and 2.51...
Journal of Electronic Materials, 2019
The current–voltage (I–V) characteristics of inhomogeneous Au/n-InP Schottky barrier (SB) diodes ... more The current–voltage (I–V) characteristics of inhomogeneous Au/n-InP Schottky barrier (SB) diodes have been investigated in the temperature range of 100 K to 300 K, and detailed numerical simulation study carried out using a physical device simulator. The experimental I–V curves for the diode in both forward- and reverse-bias conditions were fit to explain the current transport mechanisms at low temperature. Tunneling current flows through the native oxide and nanometer-sized patches embedded at the Au/n-InP interface. These patches result in a lower (local) barrier height which is temperature dependent and responsible for the diode current behaviors in the low-bias regime. The patch area is on the order of one-millionth of the total diode area, and the SB is between 0.01 eV and 0.3 eV in the patch region. The simulation results are in good agreement with the measurements in the whole explored current range extending over six orders of magnitude.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004
2018 International Conference on Communications and Electrical Engineering (ICCEE), 2018
In this paper, an analytical investigation regarding the use of double-layer antireflection coati... more In this paper, an analytical investigation regarding the use of double-layer antireflection coatings (ARC) on heterojunction solar cell (HSC), with the aim of suppressing broadband reflection is presented. In this context, we used a general characteristic-matrix to evaluate the system reflection spectra. HSC Solar cell with optimized double-layer antireflection coatings (ARC) shows an efficiency improvement of 35% over experimental single antireflection coating layer cells. This investigation highlights the impact of top multi-layer antireflection coatings (ARC) parameters. Therefore, it can be stated that these parameters are mandatory factors for improving the HSC cells photovoltaic performance.
Journal of Electronic Materials, 2017
Silicon carbide (SiC) is an important semiconductor material used in power electronics. Due to it... more Silicon carbide (SiC) is an important semiconductor material used in power electronics. Due to its high hardness and brittleness. The SILVACO-TCAD numerical simulator is used to calculate the I-V characteristic of the Schottky diode (W/4H-SiC) in the temperature range of 303–448 K. This is to study the effect of temperature on the I-V curves and assess the main parameters that characterize the Schottky diode such as the ideality factor, the height of the barrier and the series resistance. The I-V characteristics are analyzed on the basis of standard thermionic emission (TE) theory and the inhomogeneous barrier heights (BHs) assuming a Gaussian distribution. It is shown that the ideality factor decreases while the barrier height increases with increasing temperature, on the basis of TE theory. Furthermore, the homogeneous BH value of approximately 1.48 eV for the device has been obtained from the linear relationship between the temperature-dependent experimentally effective BHs and i...
Solid-State Electronics, 2006
Full modelling is reported of the capacitance of a long PIN semiconductor diode with a high conce... more Full modelling is reported of the capacitance of a long PIN semiconductor diode with a high concentration of generation-recombination (g-r) centres and different concentrations of deep traps. There are considerable differences from the textbook results given for normal lifetime diodes which have low concentrations of g-r centres. For a low density of g-r centres, the capacitance is the usual value. That is it decreases as V À1/2 with increasing reverse bias while it increases rapidly with increasing forward bias. For high density of g-r centres and in reverse bias a departure from this voltage dependence is observed, while in forward bias a negative capacitance appears. This agrees with experiment. From these results we present a physical understanding of the processes involved. There are specific applications of these results to radiation damaged devices, lifetime killed diodes and devices made from high resistance and semi-insulating materials, especially in the interpretation of the C-V curves to evaluate the fixed space charge density.
Journal of Electronic Materials, 2016
The Capacitance-Voltage characteristics (C-V) and the resistivity (ρ) of a p+nn+ silicon diode us... more The Capacitance-Voltage characteristics (C-V) and the resistivity (ρ) of a p+nn+ silicon diode used as a particle detector is numerically simulated using the finite difference method. These characteristics permit to extract the important and useful parameters for the design of a detector diode used in a harsh environment and subjected to strong fluencies, such as the depletion voltage (Vdep), the effective concentration and the maximum resistivity, the reduction rate of the donors (c) and the introduction rate of defects (g). When this junction is subjected to strong radiations, physical defects which are created in the semiconductor lattice have undesirable effects and can degrade the performance of the detectors. These defects behave like deep levels and/or generation recombination (g-r) centres. The depletion voltage and the effective concentration were calculated by using C-V characteristic. The evolution of the effective density in function with the density of traps acceptor le...
Diodes containing a high concentration of generation-recombination centres can behave in a way, w... more Diodes containing a high concentration of generation-recombination centres can behave in a way, which is not predicted by standard diode theory. Full one-dimensional modelling is reported of the current through a long PIN semiconductor diode with different concentrations of shallow donors and acceptors, deep donors and acceptors, and generation-recombination centres. From these results we present a physical understanding of the processes involved. The effect on the observed properties for short diodes is also described. An approximate analytical approach is given for a diode with a high defect concentration to complement the standard equations for a diode with a low defect concentration. The results should aid the understanding of the properties of experimental diodes, give an indication of the types of traps in the material and also suggest how their properties may be modified by additional doping. There are specific applications of these results to radiation damaged devices, lifetime killed diodes and devices made from high resistance and semi-insulating materials.
La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium... more La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium, utilisée comme détecteur de particules travaillant dans un environnement hostile et soumis à de fortes fluences, est simulé numériquement en utilisant la méthode des différences finies. Ces caractéristiques permettent d'extraire les paramètres importants et utiles pour la conception d'une diode utilisée comme détecteur, tels que la tension de déplétion (Vdep), la concentration effective, la résistivité maximale, le taux de réduction des donneurs (c) et le taux d'introduction de défauts (g). Lorsque cette jonction est soumise à des fortes radiations, des défauts structuraux sont créés qui ont des effets indésirables et peuvent dégrader les performances des détecteurs. Ces défauts se manifestent comme des pièges profonds et/ou des centres de génération-recombinaison (g-r). La tension de déplétion et la concentration effective ont été calculées en utilisant la caractéristique ...
La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium... more La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium, utilisée comme détecteur de particules travaillant dans un environnement hostile et soumis à de fortes fluences, est simulé numériquement en utilisant la méthode des différences finies. Ces caractéristiques permettent d'extraire les paramètres importants et utiles pour la conception d'une diode utilisée comme détecteur, tels que la tension de déplétion (Vdep), la concentration effective, la résistivité maximale, le taux de réduction des donneurs (c) et le taux d'introduction de défauts (g). Lorsque cette jonction est soumise à des fortes radiations, des défauts structuraux sont créés qui ont des effets indésirables et peuvent dégrader les performances des détecteurs. Ces défauts se manifestent comme des pièges profonds et/ou des centres de génération-recombinaison (g-r). La tension de déplétion et la concentration effective ont été calculées en utilisant la caractéristique ...
In this work, an analytical model is used to describe the elctrical characteristics of a dual-jun... more In this work, an analytical model is used to describe the elctrical characteristics of a dual-junction tandem solar cell performing a conversion efficiency of 32.56% under air mass 1.5 global (AM1.5G) spectrum. The tandem structure consists of a thin heterojunction top cell made of indium gallium phosphide (InGaP) on gallium arsenide (GaAs), mechanically stacked on a relatively thick germanium (Ge) substrate which acts as bottom cell. In order to obtain the best performance of such a structure, we simulate for both the upper and lower sub-cell the current density-voltage, power density-voltage, and spectral response behaviours taking into account the doping-dependent transport parameters and a wide range of minority carrier surface recombination velocities.For the proposed tandem cell, our calculations predict that optimal photovoltaic (PV) parameters, namely the short-circuit current density (Jsc), open-circuit voltage (Voc), maximum power density (Pmax), and fill factor (FF) are J...
La resistivite (ρ) d’une structure p + nn + au silicium, utilisee comme detecteur de particules t... more La resistivite (ρ) d’une structure p + nn + au silicium, utilisee comme detecteur de particules travaillant dans un environnement hostile et soumis a de fortes fluences, est simule numeriquement en utilisant la methode des differences finies. Lorsque cette jonction est soumise a des fortes radiations, des defauts structuraux sont crees qui ont des effets indesirables et peuvent degrader les performances des detecteurs. Ces defauts se manifestent comme des pieges accepteurs et des centres de generation-recombinaison (g-r). La resistivite augmente avec l’augmentation de la densite du piege accepteur pour atteindre la resistivite intrinseque (maximale).
In this work,theforward current-voltagecharacteristics of n-type Al implanted 4H-SiC pin diodesha... more In this work,theforward current-voltagecharacteristics of n-type Al implanted 4H-SiC pin diodeshave been investigated experimentally and by mean of numerical simulations in the 298-378K temperature range. Our simulations were performed using proprietary simulations software. The model parameters to be calibrated in the simulation are the electron and hole minority carriers lifetimes.The measured forward I-V characteristics showed two differentbehaviour, the leaky behaved and well behaved diode. The later diodes were considered for simulation comparison.Employing temperature-dependent carrier lifetimes as a fitting parameter, the simulation indicates that drift layer and bulk carrier lifetime ranging from 10ns to 50ns. We achieved a good agreement between simulations and measured data. The measured and the simulated forward characteristics indicate an ideality factor of about1.3for the region 2.5V-2.78Vand 2.14 in the low injection region. Activation energies of about 1.61eV and 2.51...
Journal of Electronic Materials, 2019
The current–voltage (I–V) characteristics of inhomogeneous Au/n-InP Schottky barrier (SB) diodes ... more The current–voltage (I–V) characteristics of inhomogeneous Au/n-InP Schottky barrier (SB) diodes have been investigated in the temperature range of 100 K to 300 K, and detailed numerical simulation study carried out using a physical device simulator. The experimental I–V curves for the diode in both forward- and reverse-bias conditions were fit to explain the current transport mechanisms at low temperature. Tunneling current flows through the native oxide and nanometer-sized patches embedded at the Au/n-InP interface. These patches result in a lower (local) barrier height which is temperature dependent and responsible for the diode current behaviors in the low-bias regime. The patch area is on the order of one-millionth of the total diode area, and the SB is between 0.01 eV and 0.3 eV in the patch region. The simulation results are in good agreement with the measurements in the whole explored current range extending over six orders of magnitude.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004
2018 International Conference on Communications and Electrical Engineering (ICCEE), 2018
In this paper, an analytical investigation regarding the use of double-layer antireflection coati... more In this paper, an analytical investigation regarding the use of double-layer antireflection coatings (ARC) on heterojunction solar cell (HSC), with the aim of suppressing broadband reflection is presented. In this context, we used a general characteristic-matrix to evaluate the system reflection spectra. HSC Solar cell with optimized double-layer antireflection coatings (ARC) shows an efficiency improvement of 35% over experimental single antireflection coating layer cells. This investigation highlights the impact of top multi-layer antireflection coatings (ARC) parameters. Therefore, it can be stated that these parameters are mandatory factors for improving the HSC cells photovoltaic performance.
Journal of Electronic Materials, 2017
Silicon carbide (SiC) is an important semiconductor material used in power electronics. Due to it... more Silicon carbide (SiC) is an important semiconductor material used in power electronics. Due to its high hardness and brittleness. The SILVACO-TCAD numerical simulator is used to calculate the I-V characteristic of the Schottky diode (W/4H-SiC) in the temperature range of 303–448 K. This is to study the effect of temperature on the I-V curves and assess the main parameters that characterize the Schottky diode such as the ideality factor, the height of the barrier and the series resistance. The I-V characteristics are analyzed on the basis of standard thermionic emission (TE) theory and the inhomogeneous barrier heights (BHs) assuming a Gaussian distribution. It is shown that the ideality factor decreases while the barrier height increases with increasing temperature, on the basis of TE theory. Furthermore, the homogeneous BH value of approximately 1.48 eV for the device has been obtained from the linear relationship between the temperature-dependent experimentally effective BHs and i...
Solid-State Electronics, 2006
Full modelling is reported of the capacitance of a long PIN semiconductor diode with a high conce... more Full modelling is reported of the capacitance of a long PIN semiconductor diode with a high concentration of generation-recombination (g-r) centres and different concentrations of deep traps. There are considerable differences from the textbook results given for normal lifetime diodes which have low concentrations of g-r centres. For a low density of g-r centres, the capacitance is the usual value. That is it decreases as V À1/2 with increasing reverse bias while it increases rapidly with increasing forward bias. For high density of g-r centres and in reverse bias a departure from this voltage dependence is observed, while in forward bias a negative capacitance appears. This agrees with experiment. From these results we present a physical understanding of the processes involved. There are specific applications of these results to radiation damaged devices, lifetime killed diodes and devices made from high resistance and semi-insulating materials, especially in the interpretation of the C-V curves to evaluate the fixed space charge density.
Journal of Electronic Materials, 2016
The Capacitance-Voltage characteristics (C-V) and the resistivity (ρ) of a p+nn+ silicon diode us... more The Capacitance-Voltage characteristics (C-V) and the resistivity (ρ) of a p+nn+ silicon diode used as a particle detector is numerically simulated using the finite difference method. These characteristics permit to extract the important and useful parameters for the design of a detector diode used in a harsh environment and subjected to strong fluencies, such as the depletion voltage (Vdep), the effective concentration and the maximum resistivity, the reduction rate of the donors (c) and the introduction rate of defects (g). When this junction is subjected to strong radiations, physical defects which are created in the semiconductor lattice have undesirable effects and can degrade the performance of the detectors. These defects behave like deep levels and/or generation recombination (g-r) centres. The depletion voltage and the effective concentration were calculated by using C-V characteristic. The evolution of the effective density in function with the density of traps acceptor le...
Diodes containing a high concentration of generation-recombination centres can behave in a way, w... more Diodes containing a high concentration of generation-recombination centres can behave in a way, which is not predicted by standard diode theory. Full one-dimensional modelling is reported of the current through a long PIN semiconductor diode with different concentrations of shallow donors and acceptors, deep donors and acceptors, and generation-recombination centres. From these results we present a physical understanding of the processes involved. The effect on the observed properties for short diodes is also described. An approximate analytical approach is given for a diode with a high defect concentration to complement the standard equations for a diode with a low defect concentration. The results should aid the understanding of the properties of experimental diodes, give an indication of the types of traps in the material and also suggest how their properties may be modified by additional doping. There are specific applications of these results to radiation damaged devices, lifetime killed diodes and devices made from high resistance and semi-insulating materials.
La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium... more La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium, utilisée comme détecteur de particules travaillant dans un environnement hostile et soumis à de fortes fluences, est simulé numériquement en utilisant la méthode des différences finies. Ces caractéristiques permettent d'extraire les paramètres importants et utiles pour la conception d'une diode utilisée comme détecteur, tels que la tension de déplétion (Vdep), la concentration effective, la résistivité maximale, le taux de réduction des donneurs (c) et le taux d'introduction de défauts (g). Lorsque cette jonction est soumise à des fortes radiations, des défauts structuraux sont créés qui ont des effets indésirables et peuvent dégrader les performances des détecteurs. Ces défauts se manifestent comme des pièges profonds et/ou des centres de génération-recombinaison (g-r). La tension de déplétion et la concentration effective ont été calculées en utilisant la caractéristique ...
La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium... more La caractéristique capacité-tension (C-V) et la résistivité (ρ) d’une structure p+nn+ au silicium, utilisée comme détecteur de particules travaillant dans un environnement hostile et soumis à de fortes fluences, est simulé numériquement en utilisant la méthode des différences finies. Ces caractéristiques permettent d'extraire les paramètres importants et utiles pour la conception d'une diode utilisée comme détecteur, tels que la tension de déplétion (Vdep), la concentration effective, la résistivité maximale, le taux de réduction des donneurs (c) et le taux d'introduction de défauts (g). Lorsque cette jonction est soumise à des fortes radiations, des défauts structuraux sont créés qui ont des effets indésirables et peuvent dégrader les performances des détecteurs. Ces défauts se manifestent comme des pièges profonds et/ou des centres de génération-recombinaison (g-r). La tension de déplétion et la concentration effective ont été calculées en utilisant la caractéristique ...