Sputtering of insulators in the electronic stopping region
[摘要] Using track detectors we have measured sputtering yieldsinduced by MeV light ions incident on a uranium containing glass,UO2 and UF4. No deviation from the behavior predicted by theSigmund theory was detected in the glass or the UO2. The samewas true for UF4 bombarded with 4He at 1 MeV and with 16Oand 20Ne at 100 keV. In contrast to this, 4.75 MeV 19F(+2)sputters uranium from UF4 with a yield of 5.6 ± 1.0, which isabout 3 orders of magnitude larger than expected from the Sigmundtheory. The energy dependence of the yield indicates that it isgenerated by electronic rather than nuclear stopping processes.The yield depends on the charge state of the incident fluorine butnot on the target temperature. We have also measured the energyspectrum of the uranium sputtered from the UF4. Ion explosions,thermal spikes, chemical rearrangement and induced desorption areconsidered as possible explanations for the anomalous yields.
[发布日期] [发布机构] University:California Institute of Technology;Department:Physics, Mathematics and Astronomy
[效力级别] [学科分类]
[关键词] Physics [时效性]
