Investigating Thermal Treatment of W Thin Film Deposited on 6H-SiC in Vacuum, Hydrogen and Argon

Tungsten thin film was sputter deposited on a single crystalline 6H-SiC substrate and annealed in vacuum, hydrogen and argon atmospheres at a temperature of 800 °C for 1 hour (h). The resulting atomic distribution and surface morphology were investigated by Rutherford backscattering spectrometry together with RUMP simulation and atomic force microscopy analysis techniques. The as-deposited was composed of W, O, Si and C atoms. The surface roughness of the As-deposited was about 0.4 nm with the kurtosis of about 2.44 nm indicated that the surface was relatively flat. The RUMP simulation results showed that after annealing at 800 °C, the vacuum and H2 annealed samples had two layers, while the Ar annealed samples had four layers. The formation of new layer(s) was a result of intermixing between W and SiC. AFM results indicated that Ar annealed samples had high surface roughness with large crystals than the vacuum and H2 annealed samples.