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In this work we study and optimize the single solar cell efficiency of GaN x As 1-x-y Sb y and Ga 1-x In x N y As 1-y deposed on GaAs. The solar cells are simulated, in the aim to find the best concentration of nitrogen and antimony for GaN x As 1-x-y Sb y , and indium and nitrogen for Ga 1-x In x N y As 1-y which gives us a band gap energy around 1 eV with a low strain and a maximum absorption, in fact we do not have only one value but a whole interval for both structures. In the second step we simulate the efficiency of both GaNAsSb and GaInNAs solar cells with the find concentration values in order to see which of the two structures will give a higher efficiency. We noticed that the results were obtained under AM1.5 illumination, 300 K and an ambient pressure. The two structures had a thickness of 300 nm. The N and P layers have a doping level of 1.1015 cm-3 and 1.1016 cm-3 respectively. This study gives us the possibility to produce multi-function solar cells. [ABSTRACT FROM AUTHOR]

In this work we study and optimize the single solar cell efficiency of GaN x As 1-x-y Sb y and Ga 1-x In x N y As 1-y deposed on GaAs. The solar cells are simulated, in the aim to find the best concentration of nitrogen and antimony for GaN x As 1-x-y Sb y , and indium and nitrogen for Ga 1-x In x N y As 1-y which gives us a band gap energy around 1 eV with a low strain and a maximum absorption, in fact we do not have only one value but a whole interval for both structures. In the second step we simulate the efficiency of both GaNAsSb and GaInNAs solar cells with the find concentration values in order to see which of the two structures will give a higher efficiency. We noticed that the results were obtained under AM1.5 illumination, 300 K and an ambient pressure. The two structures had a thickness of 300 nm. The N and P layers have a doping level of 1.1015 cm-3 and 1.1016 cm-3 respectively. This study gives us the possibility to produce multi-function solar cells. [ABSTRACT FROM AUTHOR]

The aim of this modeling and simulation is to study the influence of the incorporation of nitrogen (N) and aluminum (Al) on the optoelectronic properties of the structure Al x Ga 1-x As 1-y N y /Ge, and then choose the right combination (N, Al) which gives us a better conversational efficiency of the junction(Al x Ga 1-x As 1-y N y /Ge), in this study, we simulated the effect of N and Al on the strain, the band gap, carrier mobility and structure efficiency where we based on theoretical models experimentally validate, It has been shown that the Al concentration slightly affects the stress and the band gap, but it has a significant influence on the incorporation of nitrogen and in a more homogeneous way introducing a dramatic decrease in the band gap what change considerably the absorption, carrier mobility and final yield of the structure. [ABSTRACT FROM AUTHOR]

This paper reports simulations of gradual bandgap CIGS absorber and its impact on the characteristics of a solar cell. The bandgap of the CIGS absorber varies linearly and drops from E gmax (at the junction limit) to E gmin (in the vicinity of the rear contact).We introduce an effective absorption coefficient based on this variation. We will demonstrate that this gradual profile contributes to an improvement up to 171 mV of the open circuit voltage V oc of the cell that is linked to the modification of the internal electrical field distribution within the absorber. However, a joint reduction of 1.50 mA/cm 2 of short circuit current density, J sc , is observed. Overall, the conversion efficiency increases from 19.2%, for a uniform bandgap absorber structure, to 24.9% in that case of gradual bandgap. Additionally, we investigate the impact of absorber thickness and temperature on cell characteristics. [ABSTRACT FROM AUTHOR]

This paper focuses on the simulation and optimization of electrical and optical properties such as current density-voltage (J-V ) , external quantum efficiency (EQE) and the photoluminescence spectra (PL) of InSb/GaAs quantum dot solar cell (QDSC). The InSb QDs have been inserted in the intrinsic region of p-i-n GaAs solar cell. Our results have been shown that 30 InSb/GaAs QD layers provide a relative enhancement of 22.35% and 29.30% of the short-circuit current and the efficiency, respectively. With the same number of the QD layers, the absorption range edge of low energy photons has been extended from 900 to 1400 nm. The electrical features obtained for InSb/GaAs QDSC have been compared with those obtained for InAs/GaAs QDSC in goal to show the better structure. The PL spectra has been also compared with experimental result for the same structure. Moreover, the QDSC has been optimized with respect to the thickness of QDs. The optimal conversion efficiency of 10 QD layers is improved from 14.85% to 18.30% by increasing the thickness of the QDs from 5 nm to 20 nm. [ABSTRACT FROM AUTHOR]

In this work, the performance of solar cell based on CdS-n/Cu 2 ZnSnS 4 -p hetero-junction is numerically simulated. The aim of the study is to investigate the influence of thickness, defects density and bandgap energy of absorber layer CZTS and the thickness of the buffer layer CdS of the solar cell on electrical parameters J sc , V oc , FF and efficiency η of the cell. The results of our simulation allowed us to optimize the parameters above mentioned in order to get the best efficiency at the optimal band gap which corresponds to the maximum of the solar spectrum with optimal values of the electrical performances of the cell. This results lead to develop CZTS solar cells with high efficiency and low cost and give a help full indication for fabrication process. [ABSTRACT FROM AUTHOR]

This work deals with the modeling and optimization of the CuInGaSe/CdS based structure for photovoltaic applications. We took into consideration the effect of the gallium concentration and the temperature on the strain, band gap energy, absorption and efficiency of the structure. It has been demonstrated that increasing the gallium concentration increases the ban gap energy, while increasing temperature decreases it. These two parameters vary the efficiency significantly. For x = 30% and T = 300 K, the band gap energy is equal to 1.15 eV with a deformation of 0.5% and efficiency around 20%. We have also found that at this value of the band gap energy the structure absorbs most of the incident photons. Then to achieve a reliable cell based on CuInGaSe/CdS it is adequate to find a compromise between the gallium concentration in the alloy, the temperature and the strain. [ABSTRACT FROM AUTHOR]

A combination of a Copper Indium Gallium Selenide (CIGS) and Silicon (Si) layer has been recognized as an excellent choice for producing heterojunction based solar cells with improved efficiency and low cost processing techniques. The quaternary compound CIGS and silicon (Si) regions exhibit a lattice mismatch of about 5%, which induces a strain and impacts the electronic characteristics of the CIGS/Si heterojunction solar cell. A new viewpoint suggests the integration of a silicon germanium (Si 1-y Ge y) layer in the CIGS/Si region to reduce the impact of lattice mismatch. The objective of this study is to investigate how different gallium and germanium concentrations (x Ga and y Ge) affect the following factors: lattice mismatch (ε) , critical thickness (h c) and absorption coefficient (α)of CIGS/SiGe based solar cells. It also aims to analyze how these concentrations impact the primary parameters used to evaluate solar cell performance such as external quantum efficiency, short circuit current density, fill factor, open circuit voltage and conversion efficiency. The simulation results agree well with the existing theoretical and experimental literature data, confirming the suitability of the physical characteristics employed in this numerical study. By tuning the concentrations of Gallium and Germanium, it is feasible to attain an efficiency of 24% owing to the lattice compensation phenomenon in Si 1-y Ge y layers. These findings hold significant implications for the development and advancement of solar cell technology, as well as for enhancing their conversion efficiency and commercialization. • A strain-compensated CIGS/Si structure was achieved by adding SiGe layer. • The incorporation of SiGe improves the absorbance and EQE of the CIGS solar cell. • The improvement of the solar performances of the CIGS is ensured by the SiGe layer. • Optimizing Ga, Ge concentrations makes it possible to achieve an efficiency of 24%. [ABSTRACT FROM AUTHOR]

The electrical properties of InAsP/Si quantum dot solar cell (QDSC) are numerically studied and analyzed in this paper. Many effects like number of quantum dot (QD) layers inserted and Arsenic content of InAs x P 1-x on photovoltaic properties such as current density-voltage J-V and the external quantum efficiency (EQE) are investigated. Our results have been shown that the optimal Arsenic content is 0.6. With 30 InAsP/Si QDs layers, relative enhancements of about 7% and 6.70% of short-circuit current and efficiency are achieved, respectively. Otherwise, the absorption range edge of low energy photons was extended from 1120 to 1200 nm. This reveals that introduction of QDs in the intrinsic region of p -i- n Silicon (Si) solar cell enhances significantly the device characteristics beyond what has been reported for conventional semiconductor-based solar cells. [ABSTRACT FROM AUTHOR]

In recent years, the development of quantum well solar cells QWSCs (Quantum Well Solar Cells) has generated a great deal of interest. These configurations have shown good promise to optimize the low conversion efficiency of conventional solar cells because of the high rate of absorption losses present in them. In this work, we are interested in modeling and simulation of two different structures of solar cells, a simple solar cell based on silicon Si and a quantum well solar cell SiGe/Si. When a solar cell is compared to 80 quantum well layers of Si 0.8 Ge 0.2 with a pin solar cell based on Si. The short circuit current J sc increases from 23.55 to 37.48 mA/cm 2 with a relative increase of 59.15% found. In addition, the limit of the absorption band of the lower energy photons extends from 1100 nm to 2000 nm. [ABSTRACT FROM AUTHOR]

In this aim, we were interested in the optimization and simulation of pin-In 1−x Ga x N structure and InGaN multi quantum well structures for photovoltaic applications. This ternary alloy which is an III–V semiconductor presents important characteristics especially its gap energy, thus, the increase of the photons absorption of wavelengths. It has been shown that the increase in indium concentration increases the current density J sc and the maximum output power. In return, the V oc decreases consequently. For In 0.50 Ga 0.50 N structure we observed that the current density and the maximum power are respectively around 19.50 mA/cm 2 and 27.50 mW/cm 2 with a ratio of 21.65 mA/cm 2 . Also it is shown that the incorporation of the quantum well in the active region results in an increase of J sc and P max but V oc remains unchanged. The incorporation of 50 quantum well structure in the In 0.50 Ga 0.50 N gives 22 mA/cm 2 of the current density and 32 mW/cm 2 of the maximum output power. The use of the structure based on In 0.50 Ga 0.50 N (MQW) induces an efficiency of 32%. We deduced that the relative efficiency is improved by 10.9%. [ABSTRACT FROM AUTHOR]

This paper proposes a method of modeling and simulation of InAs/GaAs-based quantum dots (QDs) for solar cell. The main objective is to find the growth parameters in order to produce an optimal double heterostructure using two semiconductor materials InAs and GaAs. We are interested in particular on the impact of the growth control parameters on the physical properties of the two-dimensional InAs mono-layer. We report here a complete but non-exhaustive analysis of the electronic states of the InAs based QDs layers grown on a GaAs substrate. In this work, the reader will find the modeling and the simulation results for both rectangular and elliptical geometries of InAs QDs. In the first part of this work, we provided the change of the electronic transition energy as a function of quantum dots’ radius whilst the second one concerns the absorption coefficient as a function of the incident photon wavelength. The curves we have obtained indicate clearly that the geometrical shape of the InAs QDs does significantly modify the various parameters above. We could therefore confirm that the more appropriate geometry is the elliptical one because of the higher performances. [ABSTRACT FROM AUTHOR]

In this study, we experimentally elaborated Copper- and Indium-doped Zinc Oxide (Cu: ZnO and In: ZnO) thin films at different temperatures (T 1 = 480 °C and T 2 = 520 °C), the doping ratio were varied between 0% and 8%. Using a low cost solution-based chemical deposition, we have developed a ZnO thin film deposition process that offers fine-control of the surface morphology. It consists in spraying a volatile compound of the material to be deposited on a substrate maintained at high temperature to cause a chemical reaction in order to form at least one solid product. Therefore, the proposed ZnO doped layer is highly promising for applications for the next-generation solar cells. [ABSTRACT FROM AUTHOR]

Pyramidal textures are commonly used to reduce reflections from silicon solar cells and improve light absorption by light trapping. They are generally modelled or characterised under normal incidence. In this work, a monolayer 3D ray tracing program taking into account the polarisation of light have been developed, validated and used to compute the directional-hemispherical reflectance versus the azimuth and incidence angles for both regular upright pyramids and inverted ones, with (1 1 1) facets. Results are given for a wavelength of 0.7 μ m . They show that this reflectance is not minimal at normal incidence but for an incidence angle near 20 ° and that upright pyramids can have a lower hemispherical reflectance than inverted ones for incidence angles in the middle range. The bihemispherical reflectance is 19.6% for regular upright pyramids and 20.7% for inverted ones. The effect of the pyramids aspect ratio on the hemispherical reflectance at normal incidence is also studied. This reflectance decreases with the aspect ratio of both textures. Above an aspect ratio of 0.51, inverted pyramids have a lower hemispherical reflectance. But their bihemispherical reflectance is lower only for aspect ratios below 0.23. [ABSTRACT FROM AUTHOR]

In this work, we have studied solar cells based on AlGaInAs/InP quaternary structure to describe the behavior of electronics components. To this end, we have developed a simulation program to study the gallium Ga and aluminum Al concentrations effect on respectively the lattice mismatch, the band gap energy, the absorption and the power delivered by the solar cell. This study allows us to compare between simulation and experimental results, once the cell parameters are optimized by a judicious choice of concentrations. This work allows us either to use nanotechnologies for solar cells. [ABSTRACT FROM AUTHOR]