| Autor: |
Swansiger, W. A., Folk, D. R. |
| Předmět: |
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| Zdroj: |
Review of Scientific Instruments; Jul1987, Vol. 58 Issue 7, p1266, 5p |
| Abstrakt: |
A new ultrahigh-vacuum hydrogen permeation system is described which permits modification and characterization of the sample surface while the permeation experiment is in progress. The sample cell is mounted on a manipulator which allows it to be moved to various stations within the vacuum chamber. The sample can be modified by: (1) argon sputter cleaning; (2) sputter deposition of various materials; (3) chemical vapor deposition; and (4) exposure to various gases using a doser. XPS and AES are used for in situ surface characterization. For most experiments the inside of the sample cell is pressurized with hydrogen or deuterium and the effects of modifying the downstream surface are monitored using a quadrupole mass spectrometer, which measures the permeating flux. It is also possible to measure permeation in the opposite direction by sealing a cell to the UHV face of the sample assembly and pressurizing it with tritium. Results are reported for the permeation of deuterium through polycrystalline iron as a function of the AES oxygen to iron ratio. As the O/Fe ratio increased to 1.5, the deuterium permeability decreased by a factor of 14 at 313 K. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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