GENERAL-METHOD FOR THICKNESS DETERMINATION OF THIN BACKED FILMS - NEWFORMULATION OF BACKSCATTERING SPECTROMETRY

On the basis of the global energy change of particles going through a film, which are backscattered from the surface of the film backing, a general method is described to determine the thickness of thin films d eposited on thick substrates. Using a range formulation of the process , three analytic approximations and a quite fast computer program. to calculate the exact value are developed. Supporting measurements are p erformed on 14 targets using carbon beams. For the particular situatio n of a substrate with a heavier atomic mass than the film, precisions on the order of 1% can be obtained if uncertainties in the range data are disregarded. Comparison with other methods which are either much m ore complex, or of more limited applicability, gives consistent result s.