Alternative solutions to caesium in negative-ion sources - a study of negative-ion surface production on diamond in H2/D2 plasmas
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2017-02-23 |
| Journal | New Journal of Physics |
| Authors | Gilles Cartry, D. Kogut, K. Achkasov, Jean-Marc Layet, Thomas A. Farley |
| Institutions | CEA Cadarache, University of Liverpool |
| Citations | 43 |
Abstract
Section titled āAbstractāThis paper deals with a study of H-/D-negative ion surface production on\ndiamond in low pressure H2/D2 plasmas. A sample placed in the plasma is\nnegatively biased with respect to plasma potential. Upon positive ion impacts\non the sample, some negative ions are formed and detected according to their\nmass and energy by a mass spectrometer placed in front of the sample. The\nexperimental methods developed to study negative ion surface production and\nobtain negative ion energy and angle distribution functions are first\npresented. Different diamond materials ranging from nanocrystalline to single\ncrystal layers, either doped with boron or intrinsic, are then investigated and\ncompared with graphite. The negative ion yields obtained are presented as a\nfunction of different experimental parameters such as the exposure time, the\nsample bias which determines the positive ion impact energy and the sample\nsurface temperature. It is concluded from these experiments that the electronic\nproperties of diamond materials, among them the negative electron affinity,\nseem to be favourable for negative-ion surface production. However, the\nnegative ion yield decreases with the plasma induced defect density.\n