Laboratory experiments which mimic the acutecyclic thermal loading characteristics of pulsed power deviceswitching operation have been developed. Ni contacts to n-SiCwere the device components selected for cyclic thermal testing.Modifications of the contact-SiC materials properties in responseto cyclic thermal fatigue were quantitatively assessed viaRutherford backscattering spectrometry, nanoindentation testing,and current-voltage measurements. Decreases in nanohardnessand elastic modulus were observed in response to thermal fatigue.No compositional modifications were observed at the metal-semiconductor interface. Our results demonstrated that themajority of the material changes were initiated after the firstthermal pulse and that the effects of the subsequent thermalcycling (up to 10 pulses) were negligible. The stability of themetal-semiconductor interface after exposure to repeated pulsedthermal cycling lends support for the utilization of Ni as acontact metallization for pulsed power switching applications.
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