Wire bonding
From ArticleWorld
Wire bonding refers to the interfacing which is established between a microchip and the user. This technique is considered an integral part of semiconductor device fabrication. It is considered a very important interconnect technology, being both economical and feasible.
Types of material used
Wire which is used for wire bonding techniques is usually made up of one of the following materials:
- Gold.
- Aluminium
- Copper
The material is chosen depending upon the type of application involved and the cost factor that is to be incorporated. The diameter used may range from a few micrometers to several hundred micrometers. Larger diameters are usually needed for applications involving large power consumptions.
Main classes
The two main classes of wire-bonding are:
- Ball bonding: This is used in the case of gold and copper and requires heating. This method is more common.
- Wedge bonding: This usually involves gold or aluminium wires.
Both classes of wire bonding require a combination of pressure, heat and ultrasonic energy to force a bond.