May 14, 2012 -- Heraeus introduced its high-reliability composite aluminum/copper (CucorAl) semiconductor bonding wire, which offers strong mechanical and electrical bonds to semiconductor pads, with good thermal properties.
During passive temperature cycling and active power cycling tests, the Al-clad Cu bonding wire showed improved long-term reliability over Al bonding wires.
The aluminum coating is soft, structured around the copper core in a way that enables a reliable bonding window with existing chip metallizations and conventional wirebond tools. The thick wire is 60-70% copper by volume. It is available in 200-500µm-diameter wires.
|Figure. Heraeus CucorAl Al-clad copper bonding wire, cross-sections to show composition and bonding.|
This material composition will increase reliability of power semiconductor modules, noted Steffen Koetter, product manager, wedge bonding products from the Bonding Wire Business Unit of Heraeus, adding that power electronics are trending toward higher power density in packages. The wire can be used to assemble diodes and IGBTs, which can have junction temperatures up to 200°C. It works in concert with high-power device assembly technologies like silver sintering and diffusion soldering.
Heraeus is a precious metals and technology company with operations in precious metals, materials, and technologies, sensors, biomaterials, and medical products, as well as dental products, quartz glass, and specialty light sources. Internet: http://heraeus-materials-technology.de