A four-layer metallization Cr-Cu-NiP-Au with amorphous and nonmagnetic NiP as a barrier layer is one of the promising candidates for use in microwave integrated circuits. Multi-section Wilkinson broadband 1:2 power divider circuits are delineated photolithographically on alumina substrates metallized by Cr, TiW, Ni, NiP, copper and gold using different metallization processes. The adhesion and dc resistivity are compared for different metallization scheme. Testing and evaluation have been carried out for multi-section Wilkinson broadband 1:2 power divider in the 10 MHz-6 GHz frequency range for Cr-Cu-Au, TiW-Ni-Au and Cr-Cu-NiP-Au to see the effect of NiP. Insertion loss, return loss and isolation are measured and compared. The microwave properties do not show any appreciable differences due to the various metallizations.
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