Deposition of Sulfur on a Tungsten Surface Caused by Electron-Beam Bombardment

Abstract

The phenomenon was studied by Auger electron spectroscopy in which the appearance of sulfur on a surface of tungsten is enhanced when it is bombarded by an electron beam in an ultra-high vacuum. An additional tungsten target was provided near a tungsten specimen, and the appearing rates of sulfur on the specimen were compared when the specimen and the target were respectively bombarded by an electron beam. As a result, for the specimen used here, it was confirmed that the sulfur appearance enhanced by electron bombardment was not caused by the segregation from the bulk but was resulted from the deposition from outside of the specimen. The surface distribution of sulfur showed a sharp peak at the point of bombardment; this was elucidated as being the result of the concentration of surface sulfur towards the bombarded area of the surface.