| AVS 62nd International Symposium & Exhibition | |
| Applied Surface Science | Thursday Sessions |
| Session AS-ThP |
| Session: | Applied Surface Science Poster Session |
| Presenter: | James Ohlhausen, Sandia National Laboratories |
| Authors: | J.A. Ohlhausen, Sandia National Laboratories B. Clark, Sandia National Laboratories R. Tang, Sandia National Laboratories D. Lamppa, Sandia National Laboratories D. Susan, Sandia National Laboratories R. Sorensen, Sandia National Laboratories |
| Correspondent: | Click to Email |
The Z machine at Sandia National Laboratories is the world's most powerful and efficient laboratory X-ray radiation source. It generates 3-MV, 100-ns, 20-MA current pulses to compress target loads and produce high temperatures, high pressures, and 300-TW X-ray pulses for research in high energy density science. The Z machine target is fed by four parallel Magnetically-Insulated Transmission Lines (MITLs). The MITLs and target load hardware must be located in a high-vacuum chamber because of the exceptionally high electric- and magnetic-field stresses. The MITL electrode surfaces must be as clean as possible to maximize current delivery to the load. Residue from hardware handling, post-shot debris, and other environmental contaminants may generate electrode plasmas that contribute to current losses exceeding 6 MA for certain types of loads. Decreases in current delivery negatively affect all aspects of Z shot performance.
This analysis is part of a larger experiment to evaluate the efficacy of in-situ plasma cleaning within the Z machine’s load region. Witness samples taken from different steps during hardware preparation and installation are used to characterize surface contaminants. ToF-SIMS is uniquely suited to perform analysis of these surfaces owing to its ability to image large areas while measuring elemental and chemical information. Both organic and inorganic species were detected in the form of particles and films. Contaminants found during the Z machine load hardware lifecycle were characterized before and after plasma cleaning to determine the effectiveness of plasma processing on the specific contaminants found. Methods of acquisition, analysis and quantification will be shown. Preliminary findings from the ToF-SIMS analysis will be presented.
**Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.