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US 2020/0090829 A1Published application
Printed circuit surface finish, method of use, and assemblies made therefrom
AssigneeLilotree, L.L.C.
InventorsKunal Shah, Purvi Shah
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AssigneeLilotree, L.L.C.
InventorsKunal Shah, Purvi Shah
Estimating the term…
A surface finish for a printed circuit board (PCB) and semiconductor wafer includes a nickel disposed over an aluminum or copper conductive metal surface. A barrier layer including all or fractions of a nitrogen-containing molecule is deposited on the surface of the nickel layer to make a barrier layer/electroless nickel (BLEN) surface finish. The barrier layer allows solder to be reflowed over the surface finish. Optionally, gold (e.g., immersion gold) may be coated over the barrier layer to create a nickel/barrier layer/gold (NBG) surface treatment. Presence of the barrier layer causes the surface treatment to be smoother than a conventional electroless nickel/immersion gold (ENIG) surface finish. Presence of the barrier layer causes a subsequently applied solder joint to be stronger and less subject to brittle failure than conventional ENIG.
A method for making an electrical circuit assembly, comprising:
A method of plating one or more metallic regions of a substrate, the method comprising:
A method of plating one or more terminals of a substrate, the method comprising:
Dependencies are inferred from the claim text.