| Autor: |
D. L. Tang, Shihao Pu, Paul K. Chu, Xirong Cui, Honghui Tong, Qi Huang |
| Rok vydání: |
2007 |
| Předmět: |
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| Zdroj: |
City University of Hong Kong |
| ISSN: |
0168-583X |
| DOI: |
10.1016/j.nimb.2007.01.258 |
| Popis: |
A broad beam gas ion source based on low-pressure hollow cathode glow discharge is described. An axial magnetic filed produced by AlNiCo permanent magnets enhances the glow discharge in the ion source as a result of the magnetizing electrons between the hollow cathode and rod anode. The gas plasma is produced by magnetron hollow cathode glow discharge in the hollow cathode and a collimated broad ion beam is extracted by a four-grid accelerator system. A weak magnetic field of several millitesla is enough to ignite the magnetron glow discharge at pressure lower than 0.1 Pa, thereby enabling stable and continuous high-current discharge to form the homogeneous plasma. A four-grid accelerator, which separates the extraction and acceleration of the ion beam, is used in this design to generate the high-energy ion beam from 10 keV to 60 keV at a working pressure of 10−4 Torr. Although a higher gas pressure is necessary to maintain the low-pressure glow discharge when compared to hot filament discharge, the hollow cathode ion source is operational with reactive gases such as oxygen in the high-voltage continuous mode. A laterally uniform ion beam can be achieved by using the four-grid accelerator system. The effects of the rod anode length on the characteristics of the plasma discharge as well as ion beam extraction from the ion source are discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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