الفهرس 
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Abstract
Abstract
Porous silicon has exhibited lower reflectance and higher surface area than the pristine silicon. The porous silicon structure can effectively trap light by virtue of the large number of pores on its surface. This property of porous silicon can be applied to photovoltaic (PV) applications for more efficient silicon solar cells.
The porous silicon layers (PSLs) acting as an anti-reflection coating (ARC) formed with different surface porosities are prepared on n+ p textured crystalline CZ- silicon by electrochemical etching (ECE) in HF-based electrolyte using different current densities. The formed porosity was determined gravimetrically with in a good range of 79% - 83%, The morphological properties of the PSLs are investigated by Scanning Electron Microscopy (SEM).
The results showed that the porous silicon structure had a smaller pore size range. The optical properties of the textured surfaces are studied using photoluminescence “PL” and reflectivity measurements. The band gap energy of the prepared PSLs increases to 1.98 eV. The reflectivity of the PSLs decreases to 0.75% in a wavelength range (350–750) nm. The current-voltage (I-V) characteristics of Ag/ PS/n+p/Ag junction are investigated which reveal an increment in the resulting short-circuit current density and the open-circuit voltage up to 5.40 mA/cm2 and 0.62 V. These results show an improvement in the fill factor by 57%. The photosensitivity of PSLs solar cells showed a noticeable enhancement in quantum efficiency of the PS cells by increasing the porosity