Metallic thin film thickness determination using electron probe microanalysis

An experimental procedure to determine metallic thin film thicknesses by us ing electron probe microanalysis (EPMA) is presented. Several mortoelementa l films of Al, Ti, Cr, Cu, Nb, Mo and Au with different thicknesses, deposi ted on an Si substrate, were characterized by Rutherford backscattering spe ctrometry for thickness measurement. Characteristic x-ray intensities were measured for films, substrate and bulk standards. The ratios of these inten sities (k-ratio), were compared with those obtained from Monte Carlo simula tions based on the subroutine package PENELOPE, and good agreement was foun d. The results from simulation and experiments were added to build calibrat ion curves of k-ratio vs thickness for the monoelemental films investigated . A simple analytical function was fitted to these curves and the behavior of its parameters with atomic number was studied. Copyright (C) 2001 John W iley & Sons, Ltd.