Conversion algorithm for ERDA multielement spectra and its application to thin-film problems

A computer program was designed for the conversion of element-resolved energy spectra obtained from elastic recoil detection analysis into composition depth profiles. The algorithm is described in detail. An important feature of the program is that the contribution of the analyzed elements to the stopping power is accounted for self-consistently. Extensions of the algorithm address the problem of the simultaneous analysis of recoil and forward scattering events, respectively, and of distortions in the recoil spectra due to the presence of target constituents with isotopic distributions that cannot be resolved when using standard ionization chambers for recoil detection. Two examples are given to demonstrate how one may benefit from the capabilities of the conversion program in the context of specific thin film problems. The first example addresses compositional changes in Si3N4/C bilayers due to N-ion implantation, while the second one is dealing with the problem of impurity accumulation at the hexagonal-to-cubic phase boundary in BN films. (C) 1998 Elsevier Science B.V.