Photovoltaic Performance Improvement of Dilute Nitrides GaAs<sub>1-<i>x</i></sub>N<sub><i>x </i></sub>-Based Thin-Film Solar Cell Structur

The recent industrial revolution has increased the demand for the possible use of renewable energy sources to meet the World’s high energy requirements and to minimize the quantity of green-house gases (GHGs) in the atmosphere at once in a sustainable manner. Solar energy is one of the renewable energy sources that has garnered the most attention for sustainable energy production because it is ecologically benign, clean as well as widely available. The main issue with solar cells in comparison to traditional systems, however, continue to be their greater cost and efficiency restriction. It is anticipated that the issues will be resolved as the technology progresses as well as precious fabricating materials are used more. Dilute nitrides compound semiconductors, such as GaAs<sub>1-<i>x</i></sub>N<sub><i>x</i></sub>, GaP<sub>1-<i>x</i></sub>N<sub><i>x</i></sub> and Ga<sub>y</sub>In<sub>1-<i>y</i></sub>As<sub>1-<i>x</i></sub>N<sub><i>x</i></sub> have become promising materials because they have unique properties suitable for novel next generation optoelectronics especially photovoltaic applications. In addition, among dilute nitrides, GaAs<sub>1-<i>x</i></sub>N<sub><i>x</i></sub> attracts much attention to the researchers because of its excellent absorption coefficients and charge-transport properties, which are importantly desirable for high efficiency solar cell. Therefore, in this research work, the thin-film solar cell’s performance metrics with dilute nitrides GaAs<sub>1-<i>x</i></sub>N<sub><i>x </i></sub>as absorber layer were investigated by <I>SCAPS-1D</I>. The impacts of bandgap bowing and absorber layer’s thickness as well as operating temperatures, work functions of back-contact were evaluated to optimize open-circuited voltage (V<sub>oc</sub>), short-circuited current density (J<sub>sc</sub>), fill-factor (FF) and efficiency (η). The absorber layer’s bandgap dependence performances study revealed that efficiency around 46% can be achieved with exceptional feasibilities such as lower density of as-grown defects and reliable lifetime by tuning bandgap to 0.82eV via adjusting nitrogen concentration in GaAs<sub>1-<i>x</i></sub>N<sub><i>x</i></sub>. The assessment of performance for different absorber layer thicknesses showed that thickness around 2000nm is ideal for improving the suggested solar cell efficiency. Furthermore, higher efficiency and optimized other performance parameters obtaining at temperature 300K suggested that it is preferable to run the solar cell at that temperature to ensure steady-state functioning. Finally, it was explored by evaluating dependence of V<sub>oc</sub>, J<sub>sc</sub>, FF and η on back-contact work functions at two bandgap energies of absorber layer that specially J<sub>sc</sub> was dramatically influenced with changing bandgap of absorber layer. The research findings would be helpful for emerging renewable energy-based nanotechnology for reducing the world higher energy crisis and green-house gases at once in a sustainable manner.