Complete metallization schemes for SiC based high temperature applications were investigated with regard to their physical and chemical stability, and their electrical behaviour under the influence of a high temperature air ambient. Two metal silicides, MoSi/sub 2/ and WSi/sub 2/, were used as contacts to the 6H-SiC substrate. MoSi/sub 2/ and WSi/sub 2/ show ohmic behaviour after thermal contact formation. The specific contact resistances obtained are in the range from 10/sup -4/ to 10/sup -5/ /spl Omega/ cm/sup 2/. To keep the system design simple for these investigations, both silicides were used for on-chip interconnects. The connection to the next wiring level was realized by an 3 /spl mu/m Al cover layer and Al thick wire bonding. All systems show electrically stable behaviour during thermal storage at 400/spl deg/C for more than 1000 hours. No intermixing or degradation within the systems was found by Auger electron spectroscopy depth profile analysis and electrical measurements.
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