STRUCTURE AND PHOTO- FUNCTIONAL PROPERTIES OF TiO2 THIN FILM PREPARED BY RF HELICON MAGNETRON SPUTTERING

Abstract

Fabrication of titanium dioxide (TiO2) thin film (200nm) has been done by using RF helicon magnetron sputtering from metallic Ti target under changing of O2 flow rate and substrate temperature. Film structure was measured by X-ray diffraction (XRD). The films were examined by an X-ray photoelectron spectroscopy (XPS) to study the structure; atomic force microscopy (AFM) and field-emission scanning electron microscope (FE-SEM) were employed to investigate the surface morphology and the cross section of films, respectively. Optical properties and optical band gap were calculated by using UV-VIS spectrophotometer. Photocatalytic activity was evaluated by light induced degradation of methylene blue (MB) solution using UV and Vis light. TiO2 thin film with a rutile phase at substrate temperature 100 oC and O2 flow rate to 0.5 - 1.0sccm can be obtained, also an anatase phase can be fabricated when set substrate temperature to 300 oC and O2 flow rate to 2.5sccm. Obtained films showed a high dense with smooth surface and high crystalline. Maximum degradation rate (about 85%) of MB has been indicated at anatase phase under UV light irradiation, while under Vis light irradiation rutile and anatase mixture phase showed a maximum degradation rate (about 15%). In this work, the morphological, structural, optical, and photocatalytic properties of TiO2 thin films that were fabricated by RF helicon magnetron sputtering under change of O2 flow rate and substrate temperature have been investigated. It is expected that the change of substrate temperature and/or O2 flow rate will make ability to control the film structure.