Surface-Barrier Formation for A1 Chemisorbed on GaAs(110)

Using a localized orbital theory, we have studied the electronic and electrical properties of A1 chemisorbed on GaAs(110). We find that both the microscopic data and the macroscopic induced barrier are fully explained by the electronic structure of a new Al-As-Ga complex on the surface. This complex results from an exchange reaction in which Al replaces the surface Ga and an unexpected structural relaxation induced by the chemisorption of the metal.