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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 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]

In this paper, we report a theoretical investigation of bandgap properties of GaAsNBi based materials on GaAs substrates. We look at the influence of nitrogen (N) and bismuth (Bi) concentrations on the position of conduction and valence bands; and we show that a split of the conduction band can take place with the incorporation of N at 5% under level, while a split of the valence band of both heavy and light holes sub-bands takes place after the incorporation of Bi at 14% under level. In order to compute the transition energies, we used the VBCA k.p 16×16 model. The N and Bi concentrations effects as well as the lattice mismatch value have also been taken into account. For a couple of N and Bi concentrations of 3% and 6%, we found strained gap energy around 0.68 eV. Furthermore, we have also shown that the absorption coefficient increases significantly when the N and Bi concentrations increase. [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]