Porous silicon: fabrication, characterization and photoelectronic applications

In this paper, the nanocrystalline porous silicon (PS) films are prepared by electrochemical etching of p-type silicon wafer with current density (15 mA/cm2) and etching times on the formation nanosized pore array with a dimension of around different etching time. The films were characterized by the measurement of XRD, FTIR spectroscopy and atomic force microscopy properties (AFM). We have estimated crystallites size from X-Ray diffraction about nano scale for porous silicon and Atomic Force microscopy confirms the nanometric size Chemical fictionalization during the electrochemical etching show on the surface chemical composition of PS. The etching possesses inhomogeneous microstructures that contain a -Si clusters (Si3–Si–H) dispersed in amorphous silica matrix. From the FTIR analyses showed that the Si dangling bonds of the as-prepared PS layer have large amount of Hydrogen to form weak Si–H bonds. The atomic force microscopy investigation shows the rough silicon surface, with increasing etching process (current density and etching time) porous structure nucleates which leads to an increase in the depth and width (diameter) of surface pits. Consequently, the surface roughness also increase.