Effect of Implantation of Ba+ Ions on the Composition, Electronic and Crystal Structure of W(111) and WO2 Surfaces

• Published in: Surface investigation, x-ray, synchrotron and neutron techniques x-ray, synchrotron and neutron techniques, 2022-12, Vol.16 (6), p.992-996
• Main Authors: Umirzakov, B. E., Tashmukhamedova, D. A., Khudaykulov, F. Ya
• Format: Article
• Language: English
• Subjects: Chemical bonds; Chemistry and Materials Science; Crystal structure; Electron emission; Ion implantation; Materials Science; Photoelectrons; Surface layers; Surfaces and Interfaces; Thickness; Thin Films; Work functions
• ISSN: 1027-4510; 1819-7094
• DOI: 10.1134/S1027451022050202

It is shown that upon the implantation of Ba + ions in W, a mechanical mixture of [Ba + W] atoms is formed in the surface layer. At an ion energy of E 0 = 0.5 keV, the thickness of this layer is ~25–30 Å. Due to a decrease in the work function and an increase in the atomic density of ion-implanted layers, the maximum coefficient of secondary-electron emission σ max and the photoelectron quantum yield Y increase significantly. When the [Ba + W] system is heated to T = 900 K, the formation of a chemical bond between Ba and W atoms is not observed. In the case of the implantation of Ba + ions in WO 2 , compounds of the W–O, Ba–O, and Ba–O–W types are formed in the surface layer. In this case, the growth of σ m and Y is explained only by a decrease in the work function of the surface.