INVESTIGATION OF THE EFFECT OF ETCHING CURRENT ON TEXTURED SILICON SURFACE FOR FORMING POROUS SILICON LAYERS ACTING AS AN ANTI-REFLECTION COATING.

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-basedelectrolyte using different current densities.The morphological properties of the PSLs are investigated by scanning electron microscopy (SEM). The results show that the porous silicon structure had a smaller pore size range, and 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 1.904 eV. The reflectivity of the PSLs decreases to 0.75% in a wavelength range (350–750) nm. The current-voltage (I-V) characteristics of Al/ PS/n⁺ p/Al junction are investigated which reveal an increment in the resulting short-circuit current density and the open-circuit voltage up to 2.96 mA/cm² and 0.385 V, respectively. These results show an improvement in the fill factor by 48.5%. The photosensitivity of PSLs solar cells showed a noticeable enhancement in quantum efficiency of the PS cells by increasing the porosity.