Unraveling the Influence of Hydrofluoric Concentration on the Morphology of Porous Silicon Surfaces Fabricated through Photochemical Etching using Sunlight

May 1, 2024

Journal Iraqi Journal of Applied Physics

Publisher iraqi society for alternative and renewable energy sources and techniques

Issue 3

Volume 20

Samples of n-type porous silicon samples with negative conductivity, low resistivity (4.3x10-4 Ω.cm) and crystalline orientation (100) were prepared by photochemical etching method using sunlight as a light source. The intensity of the incident sunlight was collected and focused on the surface of the sample through a telephoto lens with a diameter of 7.5 cm and a focal length of 30 cm. The effect of changing concentrations of hydrofluoric acid (20%, 30%, and 40%) when using etching time of 30 min and illumination intensity of 6181 mW/cm2 was studied. The results of surface morphology showed forming porous layers with thicknesses 527.7, 594.7, and 663.4nm and mean grain diameters of 104.9, 121.1, and 99.80 nm, respectively.