AVS 49th International Symposium
    Applied Surface Science Monday Sessions
       Session AS-MoM

Paper AS-MoM7
Method to Quantify the Comparison of Predicted vs. Experimental Isotopic Clusters in Time of Flight Secondary Ion Mass Spectrometry for High Mass Peak Identification

Monday, November 4, 2002, 10:20 am, Room C-106

Session: SIMS
Presenter: R.W. Nowak, State University of New York at Buffalo
Authors: R.W. Nowak, State University of New York at Buffalo
C.M. Mahoney, State University of New York at Buffalo
A. Hawkridge, University of Arizona at Tucson
J.A. Gardella, State University of New York at Buffalo
Correspondent: Click to Email
Investigation of the high mass range of the ToF-SIMS spectrum (800-4000 Da.) will yield information on long range polymer interactions which affect ion formation and will provide information about the long range forces between polymer chains. Peak assignment in the high mass region is not as straight forward as in the low mass region. Isotopes of the atoms that make up the fragments combine to yield clusters of peaks, not just single peaks as seen in the low mass regions. We are able to assemble predicted isotopic clusters to compare with the collected experimental data for identification. In past reports visual comparisons of the predicted and experimental isotope cluster results were used to judge the goodness of fit between two data sets. We have developed an analytical method to construct correlation plots for comparison with these data sets and to quantify the goodness of fit between the predicted and experimental results. This paper will illustrate a method to create correlation plots of the predicted vs. experimental results. Clusters from atomic constituents in the low mass region are used as a simple model to demonstrate the application. High Mass clusters from several previously published ToF-SIMS of high mass polymers will be utilized to show the effectiveness of this method.