Investigating thermal treatment of W thin film deposited on 6H-SiC in vacuum, hydrogen and argon

Abstract

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 asdeposited 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