BONDING WIRE FOR HIGH-SPEED SIGNAL LINE

摘要

An object is to provide a bonding wire for a high-speed signal line, formed by an Ag—Pd—Pt three-element alloy or an Ag—Pd—Pt ternary alloy, that is able to transmit a stable super-high frequency signal in a several GHz band, and that does not have a strong silver sulfide (Ag2S) film even when an unstable silver sulfide layer is formed on the surface of the bonding wire. Provided is the bonding wire for the high-speed signal line formed by a three-element alloy containing 0.8 to 2.5 mass % of palladium (Pd), 0.1 to 0.7 mass % of platinum (Pt), and a balance being silver (Ag) with purity of 99.99 mass % or more, or a ternary alloy obtained by adding a trace element to the three-element alloy, in which cross section of the bonding wire is formed by a skin film and a core, and in which a surface segregation layer containing highly-concentrated silver (Ag) is present in the skin film of the silver alloy.

主权项

1. A bonding wire for a high-speed signal line that is used for connecting a pad electrode of a semiconductor device and a lead electrode on a circuit board, and is formed by an Ag—Pd—Pt ternary alloy containing a trace additive element,
wherein the bonding wire is formed by a three-element alloy containing 0.8 to 2.5 mass % of palladium (Pd), 0.1 to 0.7 mass % of platinum (Pt), and a balance being silver (Ag) with purity of 99.99 mass % or more, and wherein cross section of the bonding wire is formed by a skin film and a core, the skin film being formed by a continuously-cast outer skin layer and a surface segregation layer that is on the outer skin layer and is formed by an alloy having a higher content of silver (Ag) than that of the core.