A Comparative Study of Visible Photoluminescence from Anodized and from Chemically Stained Silicon Wafers

Abstract
Photoluminescence characteristics of anodized porous layers and chemically stained films are compared. A luminescence and an absorption band observed commonly in both materials suggest existence of similar luminous materials, though anodized samples show additional absorption bands. Consideration of both the properties of porous silicons and anodization conditions suggests that the luminous material contains silicon suboxide. The luminous material, prepared even under pure anodization conditions, is not an anodized product, but a chemical product on the surface of anodized layers, formed simultaneously with anodization.