Printed in Great Britain. 0038-1098/91 $3.00 +.00 Pergamon Press plc ADSORPTION OF ATOMIC AND MOLECULAR OXYGEN ON Si(00 1)2 x 1:

By means of Auger electron spectroscopy (AES) we have monitored the room temperature adsorption of 02 and N20 on the clean Si(0 0 1)2 x I surface. We have found, for the first time, a significant variation in the intensity ratio of the K Lt L ~ and K L23 L23 O Auger lines in the submonolayer range. This variation can be related to a change in bonding configuration of the oxygen atom/molecule in the initial adsorption stage in which the influence of inter-atomic matrix elements of the Auger process cannot be neglected. THE INITIAL stage of the oxidation of silicon sur-faces has been the subject of numerous experimental and theoretical studies. Auger electron spectroscopy (AES) has proven to be a valuable surface analysis technique inthese studies. The chemical element speci-ficity combined with low surface destruction makes AES highly suitable to check the surface cleanlines