Spectroscopic investigations of diamond/bydrogen/metal and diamond/metal interfaces

The formation of metal contacts on diamond surfaces is of decisive importance for the material's application in semiconductor devices. We present an investigation of the barrier heights of metals on diamond (111) single crystal surfaces by a combination of spectroscopic and structural methods. Two metals with different work functions and chemical reactivities, aluminium and gold were chosen as model systems for Schottky and ohmic contacts, respectively. Particular attention was paid to the role hydrogen termination of diamond has for the metal film morphology and the barrier heights. To this end diamond/metal contacts on hydrogenated and dehydrogenated diamond were investigated. Core-level spectroscopy was used to monitor chemical reactions between diamond and metal, metal-induced band bending, and the barrier heights. The morphology of the evaporated metal films was investigated by low energy electron diffraction (LEED), atomic force microscopy (AFM), and secondary electron microscopy (SEM). (C) 2001 Elsevier Science B.V. Ah rights reserved.