| Numéro |
J. Phys. Colloques
Volume 47, Numéro C7, Novembre 1986
33rd International Field Emission Symposium / 33ème Symposium International d'Emission de Champ
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| Page(s) | C7-515 - C7-520 | |
| DOI | https://doi.org/10.1051/jphyscol:1986786 | |
33rd International Field Emission Symposium / 33ème Symposium International d'Emission de Champ
J. Phys. Colloques 47 (1986) C7-515-C7-520
DOI: 10.1051/jphyscol:1986786
Department of Materials Science and Engineering, The Graduate School at Nagatsuta, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku. Yokohama 227, Japan
J. Phys. Colloques 47 (1986) C7-515-C7-520
DOI: 10.1051/jphyscol:1986786
ATOM-PROBE MASS ANALYSIS WITH A SIGNAL HEIGHT DISCRIMINATING TIMER
O. NISHIKAWA, K. OIDA et M. TOMITORIDepartment of Materials Science and Engineering, The Graduate School at Nagatsuta, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku. Yokohama 227, Japan
Abstract
At a high evaporation rate the probability of simultaneous incoming of plural ions with the same mass-to-charge ratio becomes appreciable. Thus a timer which can discriminate the height of a signal voltage generated by simultaneously incoming ions was introduced to find their correct number. The timer counted a larger number of high voltage signals for the major isotopes of W and Ni, 184W and 58Ni, than that expected from the natural abundance of these isotopes, indicating the high probability of simultaneous incomings. The number of the detected ions was corrected by weighing the number of the high voltage signals. The corrected abundance of W and Ni isotopes were found to be nearly equivalent to the natural abundances.