Surface morphology of annealed titanium /silicon bilayer in the presence of oxygen

The evolution of surface morphology and chemical composition of vacuum-annealed titanium films deposited on Si(111) substrate with native oxide is investigated. We show that changes in topography and chemical composition of the surface are related to the simultaneous transport of Si and oxygen. The elucidation of this process is done through a combined use of atomic force microscopy, scanning spreading resistance imaging, x-ray photoelectron spectroscopy, and secondary ion mass spectrometry depth profiling. Coalescence of TiO2 columnar grains formed on the silicide surface results in the coarsening of the surface. Variations in root-mean-square roughness of the surface oxide in the presence of the silicide is compared with that of pure titanium oxide for similar heat-treatment conditions.