Effects of atomic hydrogen on the surface properties of cleaved GaAs(110)

Abstract

The interaction of atomic hydrogen with cleaved n- and p-type GaAs samples has been studied by photon-emission yield spectroscopy, Auger electron spectroscopy, electron energy loss spectroscopy and low-energy electron diffraction. It is shown that the interaction occurs in two steps: first an adsorption which saturates with one H per surface atom, then a dissociation. During the adsorption stage: (i), keeping a 1*1 structure, a change in surface relaxation is very likely; (ii), H binds covalently to the substrate atoms with a sticking coefficient of 1 and (iii), a band of H-induced states about 0.22 eV wide grows at approximately 0.12 eV below the valence band edge.