Precise thickness determination of ultra thin films with X-ray reflectometry : Data evaluation and refinement

摘要

For the measurement of film thicknesses below 100 nm several experimental methods are available, e.g., ellipsometry, TEM and AFM. In this context X-ray reflectometry (XRR) is one of the best suited methodes to provide results with low uncertainties and traceability to the SI units. To evolve the prospects of XRR, the data evaluation by simulation programs has to be done very mindful. The route to a proper data evaluation is shown in this paper on the example of different thickness standards. The obstacles in the way to a correct refinement are depicted.