Resputtering phenomena and determination of composition in codeposited films

The use of standard characterization techniques to determine elemental compositions in composition spread thin films is time intensive. Combinatorial, high-throughput studies of thin film materials demand high-throughput determination of film composition. We discuss the possibility of calculating codeposited film compositions from deposition profiles obtained during single-source sputtering. In the context of dc magnetron sputtering, we find that while this technique is appropriate for the Pd,Pt,Ti system, it yields atomic ratios in a Pt,Pb composition spread thin film that vary significantly from values measured with wavelength-dispersive x-ray spectroscopy. A model for resputtering during codeposition is presented to account for these discrepancies and the model is used to calculate resputter rates during Pt,Pb codeposition. We also employ our model to estimate the resputtering susceptibility of commonly sputtered elements.