Proceedings of the 43rd International Field Emission Symposium
J. Phys. IV France 06 (1996) C5-159-C5-164
High Temperature Field Evaporation of the Metals and its Correlation with Surface IonizationO.L. Golubev
A.F.Ioffe Physical-Technical Institute, Russian Academy of Science, Polytekhnicheskaya 26, St. Petersburg 194021, Russia
High temperature field evaporation of Ir and Pt was investigated at the T = 1400 - 1700 K and electric fields F - 1 V/Å by field electron, ion and evaporation microscopy. The Arrenius plot was obtained for the process of field evaporation of Pt in these conditions. This plot gives the activation energy of the evaporation Qn=3.05 +/- 0.1 eV and preexponential factor Vo=3x1015 1/s. The value of the heat of evaporation at the presence of high electric field λF for the Pt-ions was obtained by means of image forces mode1 and value of Qn. The value of λF eV is less in comparison with sublimation energy of Pt - λo eV. The reasons of the difference between λF and λo and the mechanism of the evaporation process at these conditions are discussed.
© EDP Sciences 1996