Measurement of thin film thickness by means of a simple non-destructive radioisotopic technique

A simple quick and cheap technique for the measurement of thin metallic film thicknesses is described. The intrinsic resolution of the method is not as high as those of other techniques but its simplicity is very appreciable. Several samples, which were obtained by the vacuum deposition of nickel, chromium and zinc and which were accurately measured using a quartz microbalance system, were used to test the method. The films were successively examined with a radioisotopic gas detector Xray fluorescence apparatus, producing several calibration curves. The results so far obtained show that with the aid of such a calibration the rough estimation of an unknown coating thickness is a very quick and easy task