Secondary Emission from Films of Silver on Platinum

Abstract

Total secondary emission and energy distribution of secondary electrons have been measured for films of known thickness of silver on platinum. The depth of origin of the total secondary emission in silver as a function of primary energy, and the depth of origin of secondaries having a given energy were determined. Practically all the secondaries from primaries of 20 ev energy originate at a depth of less than 15 atomic layers, and those from primaries of 50 ev energy originate at a depth of less than 30 atomic layers. For higher primary energies, it was found that an appreciable amount of emission comes from a depth greater than 150 atomic layers. Secondaries with energies close to that of the primaries originate at a depth small compared to that of the low energy secondaries.