Bonding wire for semiconductor devices

Abstract

A high-function bonding wire enabling mitigation of damage to a neck portion, excellent in the linearity of a loop, the stability of the loop height, and the stability of the bonded shape of the bonding wire, and adapted to semiconductor mounting techniques such as lowering of the loop, thinning of the wires, narrowing of pitches, and three-dimensional mounting. The bonding wire for semiconductor devices comprises a core made of a conductive metal and a skin layer whose main component is a metal having a face-centered cubic crystal structure and different from the metal of the core and which is formed on the core. The bonding wire is characterized in that the proportion of the orientation to all the crystal orientations in the length direction in the surface of the skin layer is 50% or more.

Description

technical field [0001] The present invention relates to a bonding wire for a semiconductor device used to connect electrodes on a semiconductor element to wiring on a wiring board (lead frame, substrate, tape, etc.). Background technique [0002] Currently, thin wires (bonding wires) having a wire diameter of about 20 to 50 μm are mainly used as bonding wires for bonding electrodes on semiconductor elements to external terminals. Bonding of bonding wires is generally performed by ultrasonic and thermocompression bonding, and a general-purpose bonding device, a capillary jig in which a bonding wire is passed through for connection, or the like can be used. After the wire end of the bonding wire is heated and melted by the arc heat input, and formed into a ball by means of surface tension, the ball is crimped and bonded to the electrode of the semiconductor element heated in the range of 150-300°C, Then, bonding wires were directly bonded to the outer lead side by ultrasonic ...

AI Technical Summary

Problems solved by technology

However, copper bonding wires have problems such as reduced bonding strength due to oxidation of the wire surface of the bonding wire, and corrosion of the wire surface when resin-encapsulated.

[0014] Such a bonding wire with a multilayer structure used in semiconductors is highly expected to be put into practical use, but it has not been put into practical use so far.

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