| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Thursday Sessions |
| Session PS-ThP |
| Session: | Plasma Science and Technology Division Poster Session |
| Presenter: | Christopher Fields, Coherent Inc |
| Authors: | C. Fields, Coherent Inc M.J. Buie, Coherent Inc |
| Correspondent: | Click to Email |
Plasma treatment is used increasingly in vacuum applications to ensure removal of surface level micro-contamination which may prevent or inhibit bonding or joining applications. [1-4] We have characterized via a designed experiment the changes to the surface after plasma treatment. Stainless steel 304L was chosen as the flange material for the study. One surface was milled to provide at a minimum surface finish of 16 m in. A thorough characterization of the material was performed prior to plating including surface roughness measurements using an optical profilometer. Pre-plating results show a surface with ‘race track’ grooves around the sealing surface. The optical profilometer measured a surface roughness of 12 m in and a total roughness profile height of 105 m in. The flanges were plated with a decorative bright nickel, nickel sulfamate and a combination of the two films. The plating thickness varied from 0.5 mil to 1.5 mil. Samples were treated with either an ultrasonic aqueous clean, a plasma clean or a combination of the two. The flanges were then measured for ionic contamination via ultra-pure water extraction ion chromatography. Elemental analysis was performed using x-ray photoelectron spectroscopy (XPS). The data reveals an effective plasma treatment which removes all traces of carbon and minimizes Na. Additionally, plasma parameters were optimized in order to minimize surface roughening during processing.
References:
[1] D. Korzec, J. Rapp, D. Theirich and J. Engemann, J. Vac. Sci. Technol. A 12, 369 (1994).
[2] P. Ponath, A. B. Posadas, R. C. Hatch and A. A. Demkov, J. Vac. Sci. Technol. B 31, 031201 (2013).
[3] R. A. DiFelice, “An Investigation of Plasma Pretreatments and Plasma Polymerized Thin Films for Titanium / Polymide Adhesion, Ph.D. Thesis, Virgnia Polytechnic Institute and State University, 2001.
[4] T. S. Williams, “Surface Modification by Atmospheric Pressure Plasma for Improved Bonding”, Ph.D. Thesis, University of California at Los Angeles, 2013.