The Role of Current Density and Applied Voltage During Anodization for Porous Silicon

Porous silicon is usually formed by means of the anodization under constant current density. In order to study the role of the applied voltage during the anodization, we formed porous silicon on condition that the applied voltage was constant. The current density was not always large when the applied voltage was large. We have found that the thickness of the formed porous layer correlated with the current density while photoluminescent intensity depended on the applied voltage. When the anodization was performed with a comparatively large current density, the constant-voltage condition caused unstable current density accompanied by partial peeling of the surface.