The Behaviour of Secondary Electrons From Nickel (110) Upon Oxygen Adsorption

• Published in: Vacuum Vol. 34; no. 7; pp. 709 - 710
• Main Authors: Hanekamp, L J, Brader, S J H
• Format: Journal Article
• Language: English
• Published: 01.07.1984
• ISSN: 0042-207X

The change in the heights of the temperature dependent peaks (TDP's) in Auger electron spectroscopy measured during the initial oxidation process of a Ni(110) surface is reported. After cleaning the sample to a level below the Auger detection limit (at 740K), the oxygen coverage of the sample was raised in small exposure steps ( approx 10 exp --8 torr oxygen pressure during 10-15 s) till a saturation coverage was reached. In contrast with a contaminated surface where the TDP's are absent, the diffraction peaks, measured during the intial oxidation of a nickel surface, show a total by different behaviour. The recorded peak-heights initially reduce in size after which they increase again. The behaviour of the peaks can be explained, as McDonnell et al . did for the temperature dependence of the peak-heights (Surf. Sci ., 1973, 40, 669) by changes in the surface ordering. The differences in surface ordering can be derived from the two stage model during initial oxidation of nickel, given by Mitchell et al . (Surf. Sci ., 1977, 69, 310).--AA