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

The formation of metal contacts on diamond surfaces is of decisive importan ce for the material's application in semiconductor devices. We present an i nvestigation of the barrier heights of metals on diamond (111) single cryst al surfaces by a combination of spectroscopic and structural methods. Two m etals with different work functions and chemical reactivities, aluminium an d gold were chosen as model systems for Schottky and ohmic contacts, respec tively. Particular attention was paid to the role hydrogen termination of d iamond has for the metal film morphology and the barrier heights. To this e nd diamond/metal contacts on hydrogenated and dehydrogenated diamond were i nvestigated. Core-level spectroscopy was used to monitor chemical reactions between diamond and metal, metal-induced band bending, and the barrier hei ghts. The morphology of the evaporated metal films was investigated by low energy electron diffraction (LEED), atomic force microscopy (AFM), and seco ndary electron microscopy (SEM). (C) 2001 Elsevier Science B.V. Ah rights r eserved.