Nano-structured WO_3 Thin Films Deposited by Glancing Angle Magnetron Sputtering
WANG Mei-Han;WEN Jia-Xing;CHEN Yun;LEI Hao;School of Mechanical Engineering, Shenyang University;Surface Engineering of Materials Division, Institute of Metal Research, Chinese Academy of Sciences;
Nano-structured tungsten oxide(WO3) thin films were deposited at room temperature by glancing angle reactive magnetron sputtering and then annealed at 450℃ in air. The films were characterized by field-emission scanning electron microscope(FE-SEM) and X-ray diffraction(XRD). The WO3 thin film deposited by DC magnetron sputtering at 80° glancing angle exhibited oblique nano-column structure, while deposited by pulsed DC magnetron sputtering at the same angle exhibits nano-pore structure. After annealing at 450℃ for 3 h, the oblique nanocolums are conjunct with each other but the nano-pore structured remains with bigger pore size. XRD analysis reveals that WO3 thin films deposited at room temperature demonstrate amorphous structure. The amorphous structure will transfers to monoclinic phase after annealing at 450℃ for 1 h. Transmittance difference between colorization and bleaching of nano-structured WO3 thin film reaches 60% at wavelength of 600 nm. Electrochromic properties of nano-structured WO3 thin films are highly reversible.