Silicon, concentration versus depth profiles

Depth profiles are usually presented as atomic concentrations versus sputter time, assuming we know the rate at which the sample sputters. A typical depth profile is shown in Figure 25. It is interesting to see that at the surface there is carbon, silicon dioxide and some molybdenum. As soon as the surface layer is sputtered off (300 A), the oxygen and carbon impurities drop to constant and small values. For this CVD film, the molybdenum silicide came out to be very silicon rich. We can also see that the stoichiometry of the silicide changed with position (depth) in the film. 

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