作者：Houweling, Z.S.;Geus, J.W.;Schropp, R.E.I.;

作者单位：Nanophotonics - Physics of Devices, Debye Institute of Nanomaterials Science, Utrecht University Princetonlaan 4, 3584 CB Utrecht, Netherlands;Electron Microscopy Utrecht, Utrecht University Padualaan 8, 3584 CH Utrecht, Netherlands;Nanophotonics - Physic

刊名：Chemical vapor deposition

ISSN：0948-1907

出版年：2010-01-05

卷：16

期：41005

起页：179

止页：184

分类号：TQ175

语种：英文

关键词：Amorphous;Crystalline;Rutherford backscattering spectrometry;Thin films;Tungsten oxide;

内容简介

By resistively heating tungsten filaments in a constant air flow under a reduced pressure, nanogranular amorphous WO_3 thin films are deposited on glassy carbon substrates. The substrate surface temperature is monitored by a thermocouple. For deposition times of 15 min and longer, the films show crystallization into a monoclinic nanocrystalline WO_3 phase due to thermal radiation from the filaments. The thin films thus deposited consist of very small grains with sizes of 8-16nm for a film deposited in 5 min, and to sizes of 20-42nm for a film deposited in 60 min. By heating the bottom of the substrate to 950°C, the grains sinter to nanorods with diameters of 146±26nm with lengths of up to 750 nm. The morphology, the film thickness, the grain and the nanorod sizes of the depositions are characterized by high-resolution scanning electron microscopy (HRSEM), and the atomic species present in the films by energy-dispersive X-ray spectroscopy (EDS). The number of atoms in the films is determined by Rutherford backscattering spectrometry (RBS). The results are combined with measurements of the physical thicknesses, and thus the mass densities of the deposited films are obtained. X-ray diffraction (XRD) and Raman spectroscopy are used to characterize the deposited films crystallographically and chemically, respectively.