Thickness determination of thin polycrystalline film by grazing incidence X-ray diffraction

Thickness measurement based on the absorption of X-rays in thin films has b een tested on polycrystalline titanium nitride film deposited on a tungsten carbide substrate. The intensity of three reflections from each material w as measured for incidence angles of the primary beam ranging from 0.5 to 35 degrees. After experimental correction for texture effects, data from the TiN film and the WC substrate were fitted by known functions using least-sq uares routines. The substrate reflection intensity was found to be more sui table for determining the thickness of the overlaying thin film. The averag e thickness of TiN film (2.00 +/- 0.17 mum) determined from the substrate r eflections was in fair agreement with the average value obtained from optic al microscopy (2.2 +/- 0.8 mum). The thickness values determined from the T iN thin film reflections are very unreliable, due to high sensitivity of th e measurements to disturbing instrumental and sample effects at small angle s. (C) 2001 Elsevier Science BN. All rights reserved.