Adsorption of potassium on GaAs(110)

The adsorption of potassium on the GaAs(110) surface has been studied by ion scattering and recoiling spectroscopy (SARS) and Auger electron spectroscopy (AES). The SARS measurements indicate that a major part of the potassium atoms adsorb along the [001] gallium rows, in a region close to the sites of a new arsenic layer, and that only a minor part of the potassium atoms adsorb along the [001] arsenic rows. In agreement with this suggestion, the energy shifts in the substrate Auger peaks indicate that, at the beginning of the adsorption, the potassium atoms react preferentially with gallium atoms.