Internal oxidation of Mo–Ru coatings

The current experiment deposits Mo–Ru coatings with a Ti interlayer on silicon wafers by sputtering at 400 °C. The annealing treatments were conducted at 600 °C under atmospheres consisting of controlled oxygen contents with balanced nitrogen. After annealing in a 10 ppm O2–N2 atmosphere, surface roughness increased, apparently due to the formation of external island oxides. While annealing in a 220 ppm O2–N2 atmosphere, the relatively smooth surface was accompanied by the internal oxidation zone consisting of alternated oxygen rich and deficient layers.