International Journal of

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In this paper, a thin film silicon solar cell with anti-reflection coatings on front surface and the combination of periodic grating and photonic crystal on its back surface has been considered. The thickness and number of anti-reflection coatings, as well as the geometric and physical parameters of photonic crystal and grating are optimized to increase the optical absorption of solar cell. The simulations have been performed using the finite difference time domain method with Lumercial software. The results show that the optical absorption of solar cell has been increased significantly by utilizing the anti-reflection coatings, photonic crystal and grating.

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In this work, the effect of changing the dimensions of the layer structure on the collection of electrical charge carriers which been produced in the thin film composed of P3HT[1] and PCBM[2] that is between two electrodes, using the Monte Carlo numerical simulation with Bortez, Callus and Lebowitz algorithms, with checkered structure and different dimensions 60×15×5 sites, 60×30×5 sites, have been the conditions of the layers. At first, the average number of electrons and holes produced on the cathode and anode electrodes in two stages (simultaneous injection of excitons, without and with the presence of deep traps) was calculated and it was concluded that, by increasing layer width, the average number of electrical charge carriers collected on the electrodes has decreased, which has a direct impact on production of layer circuits and solar cell performance. Finally, the amount of external quantum efficiency of the layers was also calculated. In 60×15×5 sites layer, in two stages – without and with the presence of traps – the average value of external quantum efficiency 52.3% and 42.43% was obtained and in 60×30×5 sites layer, the value of 42.43% and 37.9% was calculated.