Leiterrahmen für eine integrierte Schaltungsanordnung

摘要

The composite includes, in succession from the nickel layer, a layer of palladium@ or soft gold@ strike, a layer of palladium-nickel alloy, a layer of palladium@ and a layer of gold@. The palladium@ or soft gold@ strike layer acts primarily as a bonding layer between the Ni and Pd-Ni alloy layers and as a layer that enhances reduction in porosity of subsequent layers, Pd-Ni alloy layer acts as a trap for base metal ions, Pd layer acts as a trap for Ni ions from the Pd-Ni alloy layer, and the outer gold@ layer synergistically enhances the quality to the Pd layer. Pd on soft Au strike layer may be 1-5 microinches thick, Pd-Ni alloy layer from 4 to 100 microinches, Pd layer from 1 to 100 microinches and the outer gold@ layer from 1 to 100 microinches thick.