AES Studies of the M/SiC Interface with Metal Carbide Formers

Abstract

ABSTRACTAfter Nichrome, Ni, Cr, and Au/Ta films are deposited onto single crystals of cubic SiC, their reactivities at the metal-semiconductor interface are studied by Auger Electron Spectroscopy. For all metals except Ni, metal carbides are detected at the interfaces. Initially these carbides tend to promote adhesion and limit the reaction with the substrate. Annealing at or above 450°C causes Ni to diffuse into the SiC and the Ta and Cr films to migrate through the capping material and away from the SiC, thereby delaminating. Development of the secondary phases at interface severely complicates the interpretation of the depth profiling data and with the uniformity of the contact film. These phases seem to be initiated at SiC defect sites where the reaction kinetics are considerably different and may be minimized with improved SiC substrates.