Unique source for scandium oxide layer deposition on tungsten for surface study of high electron emissivity

The objective was to prepare scandium oxide layers on tungsten for the surface study of Sc‐O/W(100) emitters using two design types of a compact evaporator for Sc2O3 and for metallic scandium deposition. Both of these evaporators were compatible with ultrahigh vacuum operation in a specimen chamber optimized for surface analytical measurements. The Sc2O3 evaporator allowed Sc2O3 to be deposited on a substrate while maintaining its stoichiometric composition. It was also demonstrated that scandium oxide layers could be prepared effectively on a substrate by deposition of metallic scandium followed by oxygen exposure. Copyright © 1999 John Wiley & Sons, Ltd.