Basic properties of anodized porous silicon formed under uniform current density

Abstract

Porous silicon is formed by anodization of single crystalline silicon under various current densities and HF concentrations which are the important parameters for anodization. Anodization is carried out in HF solution at constant temperature under a constant current density distribution. This paper describes the fabrication process dependencies of dissolution valence, porosity, and layer formation efficiency which are related directly to the anodization conditions. In addition, the mechanical strength of porous silicon obtained by the hardness measurement was related to the self‐standing limit of porous silicon obtained by a cylindrical model for pores arranged in the twodimensional lattice.

Methods to Evaluate Spatial Uniformity in Porous Silicon

“…For example, Desplobain et al measured the reflectivity at 17 points in a star pattern across a porous silicon sample using instruments designed for mapping of semiconductor wafers (Desplobain et al 2014). Researchers have also made point measurements in a transect across the sample (Isaji et al 2001;Aoyagi et al 1994), particularly when they have prepared porous silicon with chemical or physical gradients (Bohn and Marso 2005;Hwang et al 2008;Karlsson et al 2004;Park et al 2010). However, this review focuses mainly on approaches that provide a lateral uniformity map by making multiple measurements across the whole surface of an intact porous silicon sample.…”