A desired property for future Microsystems is the ability to work at elevated temperatures. Silicon Carbide (SiC) is the promising semiconductor for such applications because of its physical properties and its compatibility to the Silicon technology. Unsolved problems are the contact metallization and the connection to the next wiring level. Commonly in Microelectronics used wire bonds with diameters below Φ100μm show often an inadmissible loss in their mechanical stability under the influence of high temperature. To overcome this problem we have investigated the mechanical stability of different monometallic thick wire bonding interconnections. The main focus was given to 250μm thick AlMg0.5 wire using wedge/wedge bonding as well as ball/wedge bonding. By pulltest a 25% loss in the wire strength was found after a thermal treatment at 400°C independent from the time. It is worth mention that the remaining strength is sufficient for reliable connections and far away from a critical value. No change in the strength of the first and second bonds was detectable by sheartests. It was found that a diffusion of the Magnesium (Mg) content of the wire to the padmetallization has occurred. The investigations were completed by Auger Electron Spectroscopy (AES) of the diffusion zone. Both technological versions have been shown the same behaviour without significant differences in their mechanical stability. The advantage of ball/wedge bonding is the better deep-access-capability in such applications. It was resumed, that Aluminium thick wire bonding is an applicable technology for high temperature stable connections (without too much thermal cycling). Investigations are under way to find the maximum operating temperature.
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