Formation of porous silicon on N-type Si (100) and Si (111) substrates by electrochemical anodization method

Porous silicon (PSi) was formed on n-type Si (100) and Si (111) substrates via the electrochemical anodization method. The samples were anodized in HF: ethanol solution (1:1) and flowed with a varied current density of 10, 20, 30, 40, and 50 mA/cm(2) for 30 min. The reflectance, the pores size, and the pores depth of PSi were characterized by UV-Vis spectroscopy, SEM instrument, and Dektak Profilometer, respectively. The higher current density results in lower reflectance of PSi on both Si (100) and Si (111) substrates, while SEM images and Dektak tests confirmed that the pore depth and the pore size of PSi increased. It is concluded that PSi could be applied to solar cell devices as an anti-reflective surface. PSi reflectance on Si (100) is lower than on the Si (111) substrate. It suggested that in DSSC, PSi on Si (100) could be considered to have better anti-reflective properties. (C) 2020 Elsevier Ltd. All rights reserved.