Formation of nanoporous titanium oxide films on silicon substrates using an anodization process

Abstract

The formation of nanoporous TiO2 by anodization of titanium films deposited on silicon substrates was investigated. Films with homogeneously distributed pores having an average pore diameter of 25 nm and interpore distance of 40 nm were obtained by anodization in an aqueous HF electrolyte solution after a comprehensive investigation of the anodization conditions. It was shown that the magnitude of the anodization current and voltage have significant roles in the formation of different surface morphologies with different pore dimensions, ranging from big pits to nanosize porous structures. The study showed that the nanoporous structure is formed only in 0.5–1.0 wt% HF solution while keeping the anodizing potential at 3–5 V. The porous TiO2 films were characterized using scanning electron microscopy and x-ray diffraction techniques, and their formation conditions are discussed. In addition, a growth mechanism model is presented to explain the formation of different surface structures.

Enhancing Light Extraction of Inorganic Scintillators Using Photonic Crystals

“…The material is kept in an acidic solution while applying an electrical bias, resulting in self-ordered, nanometer-scale pores in the material. The processes of anodization of both aluminum oxide [66,67] and titanium oxide [68,69] are well studied. Since aluminum oxide does not have a high RI, RI = 1.76, for our application, it is useful to deposit a layer of, for instance, a higher RI material on top of the structure [66].…”

A credible role of copper oxide on structure of nanocrystalline mesoporous titanium dioxide

“…The anatase phase has a higher photocatalytic and photoelectrical conversion activity than amorphous, rutile and brookite phases. Therefore, mesoporous TiO 2 containing the high crystallization of anatase has attracted much attention due to its high surface area and a passage wide enough for the ingress of reactants and egress of product, which enhances the surface reactions [1][2][3][4].…”

Preparation and characterization of fouling-resistant photocatalytic metal membrane embedded with self-organized TiO2 nano tube

“…Anodization is generally known as a useful method for modifying the surface structures to obtain nanoporous or doi: 10.2166/wst.2010.066 nanotubular structures (Lee et al 2004;Kim et al 2006;Francioso & Siciliano 2006;Miyauchi et al 2006;Yu et al 2006;Yu et al 2008). The surface of 'valve metals' (Ti, Al, Ta, Nb and so on) is instantaneously covered with a native oxide film when these metals are exposed to aerobic environment and can be used for fabricating ordered pore array (Masuda & Fukuda 1995;Masuda et al 1997).…”