| AVS 55th International Symposium & Exhibition | |
| Applied Surface Science | Wednesday Sessions |
| Session AS-WeM |
| Session: | Advanced Data Analysis for Surface Characterization |
| Presenter: | A.S. Lea, Pacific Northwest National Laboratory |
| Authors: | A.S. Lea, Pacific Northwest National Laboratory D.R. Sisk, Pacific Northwest National Laboratory M.H. Engelhard, Pacific Northwest National Laboratory J.E. Castle, University of Surrey, UK D.R. Baer, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
The application of x-ray photoelectron spectroscopy (XPS) to analyze different types of materials appears to be growing rapidly around the world. In our Department of Energy National User Facility the Environmental Molecular Sciences Laboratory (EMSL) we currently have user requests for thousands of hours per year of XPS based experiments and more routine sample analysis. The real-time (or near real-time) analysis of the XPS data as it is collected has significant potential advantages to scientists and instrument operators in that it has the potential to qualitatively alter the way experiments are done. Such endeavors have the potential, not only to improve the turn-around time for data analysis and the sophistication of data analysis reportable to the User, but also to reduce the labor involved in data analysis, resulting in significant time (and cost) savings. We are developing a prototypical real–time data analysis capability to analyze x-ray photoelectron spectroscopy (XPS) data generated in EMSL. Our goals are to provide atomic composition, carbon contamination layer thickness and component segregation (layer) information as soon as adequate data is collected on a specimen. Because of the high user need and previous efforts to design an XPS expert system, XPS is a good candidate for development of a near real time data analysis capability. Our real-time data analysis package follows many elements of the expert system approach proposed by Castle.1 A set of rules and algorithms are used to address a well defined series of analysis objectives (based on the needs of the XPS analysis) to characterize the surface in terms of atomic concentration, layer sequences, and enrichment/depletion of elements as a function of depth. For each goal, rules have been developed to determine whether the stated goals are met. The real-time analysis package evaluates the rules by automated interpretation of the wide-scan (survey) spectra. Once the goals have been met, the real-time analysis package generates a report that includes, in addition to the above stated goals: a first level approximation of surface composition and metadata associated with this analysis, which will be stored with the datafile produced by the data analysis package.
1 Castle, J.E., J. Vac. Sci. Technol. A (2007) 25, 1-27.