A gold-tin alloy that can be used to bond electronic components, such as ceramic packages and lead pins, without the need for a washing process. The alloy’s low-temperature annealing process also minimizes the generation of residue, a source of corrosion on the bonding surface.

The first gold-tin alloy that can be bonded to materials such as ceramics, metalized substrates and conductive surfaces. It is an alternative to traditional soldering and bonding products that contain lead, such as gold-lead eutectic, a high-temperature reflow solder, and lead-free tin.

Until recently, a variety of alloys containing copper, tin and zinc were the most common. These are called “tumbaga.” The alloy was used by pre-Columbian cultures in South and Central America for religious objects and is made of about 97% copper and 7% gold, although the proportions of each can vary widely. Tumbaga can be cast, drawn, hammered, forged, soldered, welded, plated and polished. It can also be carved, engraved, embossed and inlaid.

For many years it was believed that gold dissolved in other metals, both liquid and solid, forming a complete series of homogeneous alloys. This belief was based on freezing point curves and microscopic examination, which show that the alloys at the lowest and highest freezing points closely resemble the silver-copper series. The alloys with lower freezing points also exhibit marked segregation on solidification. However, this segregation has been ascribed to the formation of eutectic alloys separating crystals of gold from one another.