Effect of Plasma Process on the WO₃ Thin Films

Abstract:

O₂ plasma treatment induces a transformation in the structure of WO₃ thin films, converting them into a crystalline structure. Amorphous WO₃ thin films were deposited on silicon produced by pulsed DC reactive magnetron sputtering at room temperature. The as-deposited films were treated with oxygen plasma powered by an RF generator. During the plasma treatment, the pressures were set at 1 x 10^-1 to 1x 10^-2 mbar, while the RF supplied powers at 100 W and 200 W. The effects of plasma treatment induced modifications of structure and physical properties of WO₃ thin films. Several techniques were used to characterize microstructure, phase composition and surface morphology of the films including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM). An RF generator powered the O₂ plasma treatment on the as-deposited films. During the plasma treatment, the pressures were set at 1.0x10^-1and 1.0x10^-2 while the RF powers was supplied at 100 and 200 watt, respectively. The film's crystal structure changed at 200W plasma power and 1 x 10^-2 mbar operating pressure. The O₂ plasma treatment significantly changed the thickness of the films, probably as a result of changes in the packing density and surface etching. The experimental results suggest that the plasma treatment excitation process after crystallization can transform the films' amorphous structure into a crystalline structure.

• Periodical: Solid State Phenomena (Volume 372)
• Pages: 87-92
• DOI: https://doi.org/10.4028/p-WuDU05
• Online since: July 2025
• Authors: Nujira Kothanamn, Amarin Tongkratoke, Porawit Jiandon, Chatpawee Hom On*
• Keywords: Crystallization, O₂ Plasma Treatment, Thin Films, Tungsten Oxide

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