Photoemission Studies of Room-Temperature Oxidized Gallium Surfaces

• Published in: Surface science 1982-06, Vol.118 (1-2), p.248-256
• Main Authors: Su, C Y, Skeath, P R, Lindau, I, Spicer, W E
• Format: Article
• Language: English
• ISSN: 0039-6028

Cf. ibid. , p 257. The oxidation of sub in situ prepared Ga films at room temperature has been studied with photoemission. Direct formation of Ga sub 2 O sub 3 has been observed. An interpretation of the valence band spectrum of Ga sub 2 O sub 3 in terms of the electronic structure of Ga sub 2 O sub 3 is offered. Correspondence between a donor-like bonding band, due to the interaction between a doubly occupied oxygen lone pair and an empty Ga orbital, an oxygen non-bonding band, and a Ga--O--Ga bonding band and three features in the valence band spectrum of oxidized Ga has been found. Interpretation of the photoemission spectrum of the recently reported chemisorbed-oxygen on Ga metal at 70K is suggested based on the understanding of the spectrum of Ga sub 2 O sub 3 . The possible existence of an intermediate oxidation state formed by the room temperature oxidation of Ga films is also discussed based on the presence of intermediate chemical shifts ( Delta E < = 2.0 eV) in the Ga-3d level. 11 ref.--AA