Investigation of interface states and fermi level pinning mechanisms with metals on InP(110) surfaces - Cao, R.; Miyano, K.; Lindau, I.; Spicer, W.E. (Elsevier)
Metal/InP(110) interfaces have been systematically studied using photoelectron Spectroscopy. This work aims at understanding the physical nature of interface states and Fermi level pinning mechanisms. Clear-cut experimental evidence shows that two types of interface states are responsible for Fermi level pinning. At the disrupted interfaces which occur at room temperature, a large amount of defects are generated during various interfacial processes and pin the surface Fermi levels around 0.95 eV above the valence band maximum (VBM). On the contrary, much fewer defects are present at the nearly perfect interfaces which are obtainable at reduced temperature. In these cases, the metal induced gap states play an overwhelming role, and the Fermi level is pinned around 0.75 eV above the VBM. It is also concluded that interplay between the two mechanisms should be taken into account in order to understand the process of Schottky barrier formation.
http://linkinghub.elsevier.com/retrieve/pii/0368-2048(90)80182-A
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