SCHOTTKY-BARRIER FORMATION FOR NONIDEAL INTERFACES - AS-RICH GAAS(110) METAL JUNCTIONS

Schottky barriers have been analyzed theoretically for clean and passi vated GaAs(110)-surfaces. Passivation is obtained by the deposition of an As-monolayer on the semiconductor surface. The Schottky-barrier fo rmation is studied for a K-monolayer on the clean and passivated semic onductor surfaces. Our results show that passivation changes dramatica lly the mechanism of Schottky-barrier formation. These differences are explained by the different states found for the ideal and passivated surfaces. In particular we find that the As-passivation decreases the n-type Schottky barrier for K by 0.6 eV.