Morphological evolution of the porous silicon surface for different etching time and current density in hf-ethanol solution

Abstract

Porous silicon samples were obtained by the anodization etching process of a n-type silicon wafer. The pores formation was investigated taking into account the anodization time. Scanning Electron Microscopy and Optical Profilometry were used to characterize the morphology, pore size, pore depth, thickness, roughness, surface area and also the morphological evolution of porous silicon layer. The formed porous silicon layer showed a tendency to increase the pore size, pore depth, roughness and surface area as a function of the etching time. The porous silicon was obtained at different etching times and at a fixed current density. The experimental results showed that the porosity of the porous silicon prepared under different anodization times can be controlled.