Photocatalytic Titanium Oxide Film Deposition by Atmospheric TPCVD Using Air as the Working Gas

Abstract

Thermal plasma chemical vapor deposition (TPCVD) is a rapid film deposition process using thermal plasma. Various functional material films, such as silicon carbide and titanium oxide <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$({\rm TiO}_{2})$</tex></formula> , have been successfully deposited so far. In the case of oxide film deposition especially, film deposition can be carried out in the open air. Therefore, TPCVD is hoped to be a low-cost deposition process for functional material films. However, since Ar has been mainly used as the working gas in the case of a conventional TPCVD, the running cost is high in comparison with the conventional CVD processes. In this paper, in order to decrease the running cost, an atmospheric TPCVD equipment using air as the working gas is developed and <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${\rm TiO}_{2}$</tex></formula> film deposition is carried out using this equipment. Consequently, it is proved that photocatalytic <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${\rm TiO}_{2}$</tex></formula> films could be deposited on the condition of a deposition distance of 50 mm, even in the case of using air as the working gas.