| abstract |
A semiconductor device has a leadframe with a structure made of a base metal ( 105 ), wherein the structure consists of a chip mount pad ( 302 ) and a plurality of lead segments ( 303 ). Covering the base metal are, consecutively, a continuous nickel layer ( 201 ) on the base metal, a layer of palladium on the nickel, wherein the palladium layer ( 203 ) on the chip side of the structure is thicker than the palladium layer ( 202 ) opposite the chip, and a gold layer ( 204 ) on the palladium layer ( 202 ) opposite the chip. A semiconductor chip ( 310 ) is attached to the chip mount pad and conductive connections ( 312 ) span from the chip to the lead segments. Polymeric encapsulation compound ( 320 ) covers the chip, the connections, and portions of the lead segments, but leaves other segment portions available for solder reflow attachment to external parts. |