Electronic devices based on silicon carbide (SiC) represent a good choice for a variety of new high temperature, high power electronic applications. Moreover, SiC ceramics have great potentials for use in harsh environments. Nevertheless, many technical challenges still need to be addressed, including high temperature stability. Results obtained on several levels in the development of a SiC-based package are presented.; The sealing of ceramic packages is generally accomplished using specialty glasses. Several commercial glasses were tested in view of their application as glass sealants. The reactions between SiC and certain oxides present in the glasses were responsible for the formation of CO gas. Selection criteria were developed based on thermodynamic calculations. This approach provides valuable information in tailoring suitable glasses.; The oxidation of SiC in air results in the formation of silica that does not prove to be protective above about 1800 K because of interfacial reactions with its SiC substrate. The oxidation of both single crystal and polycrystalline SiC, between 973 and 2053 K, resulted in the formation of quartz, cristobalite or tridymite, which are the stable crystalline polymorphs of silica at ambient pressure. The polymorphs were pure SiO2, and contamination of the oxide scales from the oxidizing environment did not occur. The only variable affecting the occurrence of a specific polymorph was the oxidation temperature. Cristobalite was formed at temperatures ≥ 1673 K, tridymite between 1073 and 1573 K, while quartz formed at 973 K. Cristobalite was observed to grow in a spherulitic fashion from amorphous silica. This was not the case for tridymite and quartz, which appeared to grow as oriented crystalline films. The presence of a thin layer of silicon oxycarbide was detected at the SiC/SiO 2 interface.; Formation of reliable and homogeneous interconnects can be a critical issue for demanding applications. The approach that was undertaken to interconnect nickel leads to the device is that of the transient liquid phase bonding, where a bond is formed at the tungsten metal interface through isothermal solidification of a copper interlayer. The refractory metal and nickel contact wire alloy with the interlayer to produce a strong, electrically conductive bond.
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