Fermi level movement at the Cs/GaAsthinsp;(110) interfaces

摘要

Fermi level (Efthinsp;) movement and overlayer metallization at room temperature (RT) and 110 K lowhyphen;temperature (LT) Cs/GaAsthinsp;(110) interfaces are studied using photoemission. Initialphyphen;type GaAs band bending is attributed to the surface donor states that originate from Cs atom chemisorption. TheEfstabilization at RT and LT is interpreted in terms of defects and the metalhyphen;induced gap states and the interplay between them. For the latter to dominate, fewer defects and establishment of overlayer metallicity are necessary.