Wedge Bonding

Wedge Bonding

Wedge Bonding works by using a Wedge Bonder – in descriptive terms this is how it works: a wire is passed through the wedge tool over the microchip, the capillary then settles over the area that needs to be wired up (usually called the die or substrate). The tool descends to the surface so that the wire is pressed between the substrate and the tip of the capillary (the surface is usually gold, but could also be palladium or silver). Ultrasonic energy is applied and the result is a wedge bond.

Palomar has developed a method called "Chain Bonding", which is a cost effective alternative to wedge bonding and uses a modern Wire Bonder / Ball Bonder.

Wedge Bonding process example

Wedge Bonding Applications

Wedge bonding can be a great solution for performing low profile or fine pitch interconnects and is also well suited for running stitch interconnects (also known as die-to-die bonding and chain bonding), reverse bonding, and ribbon bonding. Designs that require interconnecting from die to die or from a substrate to a die, also called reverse bonding, could benefit from the use of a wedge bonder.

Wedge Emulation with a Ball Bonder using Chain Bonding can be an excellent alternative to using a wedge bonder to perform the interconnect (see article “The Great Debate: Ball vs. Wedge”).

A Brief History in Wedge Bonding

The first wedge bonder was a thermocompression wedge bonder designed in 1957. It wasn’t until the 1960’s that ultrasonic wedge bonding was introduced. Beginning in the 1970’s thermosonic wedge bonding was being performed. By the time the 1980’s rolled around, automated wedge bonders and automated wire bonders were being produced and sold all over the world. Among the top designers and manufacturers for wedge and wire bond technology, was Hughes Aircraft.

Palomar Technologies’, formerly Hughes Aircraft, has continued this legacy of wedge and wire bonder technology, being deeply rooted and established in power, precision, performance and success.