Volume 11 Issue 3 ( September 2024)

The photoelectrochemical method using a green laser has been employed in forming PSi on n-type Si (100) surfaces. The volume ratio of HF and ethanol was varied at 1:1, 1:3, and 3:1 to obtain PSi that coincide as an anti-reflective material while current density and etching time were maintained constant. Based on the SEM images, ethanol is dominant in controlling the pore size and distribution. The quantum confinement effect occurs in PSi so that the optical bandgap energy (Eg) of PSi increases with increasing the porosity and decreasing the thickness of PSi. Also, the absorbance of PSi is high for large pore sizes. Due to PSi at a ratio of 1:3 having high porosity and high absorbance, these samples are better materials as anti-reflection layers in Si solar cells application than at ratios of 3:1 and 1:1. In addition, for all ratios, PSi formed a polycrystalline where Si and SiO2 structures co- exist.

Keywords: Porous silicon; N-type Si(100); Photoelectrochemical; Reflectance; Absorbance