GaAs solar cells have contributed as concentrators and space solar cells and are anticipated to create new markets, such as large-scale electric power systems and PV cell-powered electric vehicles. Therefore, further improvement of higher efficiency and low-cost GaAs solar cells is significant in the PV solar system. However, the GaAs solar module is too expensive as gallium resources are limited. The highest efficiency of GaAs semiconductors was accomplished with a triple-junction, reaching up to 42.3%. Many studies on single-junction GaAs cells achieved 28.8% power efficiency. Double heterojunction GaAs solar cells achieved the highest energy conversion efficiency by. GaAs has a high resistivity to heat and radiation that affect the module performance compared to (c-Si) solar cells. Thus, no transfer of momentum is required to excite an electron from the valence to the conduction band. It has a direct bandgap equal to 1.42 eV at room temperature (300 K) where the lowest conduction band is vertically aligned with the highest valence band. GaAs has a zinc blend crystal structure that consists of four (As) neighbouring atoms with every (Ga) atom and four neighbours (Ga) with every (As) atom, referring to the Figure 8. Therefore, the average valency is four electrons per atom. GaAs (III-V binary semiconductor), a widely used electronic semiconductor in solar cells, is a crystalline PV material based on an element with three valence electrons, gallium (Ga), and an element with five valence electrons, arsenic (As). Another experiment by demonstrated a PV GaAs device based on single junction thin film under the non-concentrated light (1 sun illumination), achieving a high efficiency of 27.6%. The PCE of the fabricated single-junction GaAs thin-film solar cells reached 22.08% under Air Mass (AM) 1.5 global illumination. A metal combination of AuBe/Pt/Au was employed as a new p-type ohmic contact. Highly efficient n-on-p single-junction GaAs thin-film solar cells have been fabricated by. For a single-junction PV cell, GaAs is best suited to achieve the highest efficiency, nearly 30%, due to its bandgap (1.42 eV) being near to the ideal bandgap and high absorption coefficient, which offers substantial benefit in the design and fabrication of highly efficient PV devices. First, a single-junction solar cell, which consists of a highly doped emitter layer and a lightly doped base layer. Solar cells can be fabricated in different designs. The design of a PV cell is defined by the cell structure. All electrons and holes are swept out of the depletion region by a generated electric field, which prevents any additional flow of the charge carriers, as shown Figure 3 below. ![]() The diffusion of electrons and holes will create a current called diffusion current ‘I diff’ and a depleted area of charge carriers, referred to as the depletion region or space charge region. The consequent jumps of the valence electrons can be noted as a motion of the holes. Likewise, a net of negatively charged acceptor atoms is left behind in the p-n junction near the p-zone as holes diffuse from p-region to n-region. When n-region and p-region semiconductors are brought into contact, electrons of the n-section will diffuse into the p-section leaving a region of positively charged donor atoms in the p-n interface near the n-zone. The doping process creates additional mobile carriers called majority carriers in each respective region. A diode is a single crystal semiconductor material such as silicon, having one side doped with pentavalent impurities forming n-type and another side doped with trivalent impurities as p-type. Moreover, the paper explores the role of numerical and mathematical modelling of PV cells by MATLAB/Simulink and COMSOL in evaluating the power conversion efficiency (PCE) of the PV cells and determining the main parameters affecting the power output at various conditions.Ī solar cell in a basic term is a semiconductor diode that has been carefully designed to generate power from the sunlight. ![]() Furthermore, the paper presents the standard model of solar cells with the application of this model to different PV technologies together with the main findings. This paper reviews many basics of photovoltaic (PV) cells, such as the working principle of the PV cell, main physical properties of PV cell materials, the significance of gallium arsenide (GaAs) thin films in solar technology, their prospects, and some mathematical analysis of p-n junction solar cells. The device to convert solar energy to electrical energy, a solar cell, must be reliable and cost-effective to compete with traditional resources. Employing sunlight to produce electrical energy has been demonstrated to be one of the most promising solutions to the world’s energy crisis.
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