Wire bonding

Gold wire ball-bonded on a silicon die
Aluminium wires wedge-bonded to a BC160 transistor die
The interconnections in a power package are made using thick (250 to 400 μm), wedge-bonded, aluminium wires.
Inside a wire-bonded BGA package. This package has an Nvidia GeForce 256 GPU.

Wire bonding is a method of making interconnections between an integrated circuit (IC) or other semiconductor device and its packaging during semiconductor device fabrication. Wire bonding can also be used to connect an IC to other electronics or to connect from one printed circuit board (PCB) to another, although these are less common. Wire bonding is generally considered the most cost-effective and flexible interconnect technology and is used to assemble the vast majority of semiconductor packages. Wire bonding can be used at frequencies above 100 GHz.[1]

  1. ^ V. Valenta et al., "Design and experimental evaluation of compensated bondwire interconnects above 100 GHz", International Journal of Microwave and Wireless Technologies, 2015.