Effect of substrate temperature variation on nanostructured WC films prepared using HFCVD technique

Nanocrystalline tungsten carbide thin films are deposited on quartz substrates using hot-filament chemical vapor deposition technique. The influence of the substrate temperature on the nanostructured WC films is studied. The scanning electron microscopy indicates that the size of nanoparticles increases from 50 to 150 nm with an increase of substrate temperature from 400 °C to 800 °C. The crystalline structures, chemical bonds, and nanocomposition of WC films are characterized using X-ray diffraction, X-ray photoelectron spectroscopy, Raman scattering, and energy dispersion spectroscopy. The evolution of crystalline structures from α-WC to α-W₂C following variation of substrate temperature is observed.