The oxidation process of the K/GaAs(110) interface

PASSEGGI (JR.), M.C.G.; FERRÓN, J.

JOURNAL OF PHYSICS CONDENSED MATTER

IOP Publishing Ltd.

Lugar: Bristol, United Kingdom; Año: 1999 vol. 11 p. 6725 - 6735

0953-8984

The K-promoted oxidation of GaAs(110) has been studied using Auger electron spectroscopy and principal component analysis. We found that the oxidation process of the interface is not a properly catalytic mechanism, as the alkali metal reacts forming compounds that become mixed with the substrate oxidation products. The substrate oxidation process starts, as well as that for the adsorbate, from the beginning of the oxygen exposure without showing an adsorption stage like that observed during the oxidation process of the clean GaAs surface. The alkali-promoted oxidation of GaAs involves the simultaneous oxidation of all the elements present, K, As and Ga, and neither induction nor adsorption stages are observed.