CRATERS PRODUCED ON Al
نویسنده
چکیده
Transmission electron microscopy has been used to observe craters produced 7 on Al, Cu and Au at room temperature by the impact of Ar clusters. Irradiations were made at normal incidence with Ar clusters of either 100 or 1000 atoms having an energy of 100 keV. The probability of a cluster to make a crater decreases with increasing target atomic mass or density, At a given total energy, the probability of a cluster to make a crater increases with increasing cluster size. This increase in cratering rate with decreasing energy per atom in the cluster occurs because of greater energy deposition near the specimen surface due to increased rate of energy loss by individual atoms in the cluster. PACS: 61.35.BS, 68.55, 61.72.Ff
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