Oxygen interaction with Cu(100) studied by AES, ELS, Leed and work function changes
Abstract
The interaction of oxygen with Cu(100) surfaces was investigated from 85 to 800 K by AES, ELS, LEED and work function change. At T⩾300 K three different states of oxygen bonding are observed:
1. Chemisorption of oxygen (dosages up to ∼102L), indicated by an increase of the work function change Δφ and O(KLL) signal height.
2. Incorporation of oxygen into the Cu sublayer with further oxygen uptake accompanied by a decrease of Δφ, and a shift of the O(KLL) Auger transition to lower energy (∼102−106L).
3. Growing of Cu(I) oxide, characterized by an increase of Δφ, shifts of the oxygen and copper Auger transitions and significant changes in ELS and AES line shapes (⩾3×106L, 10−3−5×10−1torr). At low temperature (85 K) a second adsorbed oxygen species is detected.
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