Physical properties characterization ofW03 films grown by hot-filament metal oxide deposition

Abstract

W03 is grown by hot-filament metal oxide deposition (HFMOD) technique under atmospheric pressure and an oxygen atmosphere. By X-ray diffraction obtains that W03 presents mainly monoclinic crystalline phase. The chemical stoichiometry is obtained by X-ray Photoelectron Spectroscopy ( XPS). TheIR spec­ trum of the as-grown W03 presents broad peaks in the range of 1100 to 3600 em - '. A broad band in the 2200 to 3600 cm- 1 region and the peaks sited at 1645 and 1432 em - 1 a re well resolved. which a re originated from moisture and are assigned to v( OI-1 ) and 8(01-I) modes of adsorbed water and the corre­ sponding tungsten oxide vibrations are in infrared region from 400 to 1453 em-' and around 3492 em 1 • which correspond to tungsten-oxygen (W-0) stretching, bending and lattice modes. The Raman spec­ trum shows intense peaks a t 80 I. 710. 262 and 61 em-' that are typical Raman peaks of crystalline W03 (m-phase) that correspond to stretching vibrations of the br i dging oxygen, which are assigned to W-0 stretching (v) and W-0 bending (8) modes. respectively. By transmittance measurements obtains that the W03 band gap can be varied from 2.92 to 3.13 eV in the investigated annealing temperature range.