Wire bonding is the part of the fabrication that allows an electrical component to communicate with the outside world. A thin electrically conductive wire – typically gold, aluminium, copper or silver – is used to allow electricity to flow from contacts on the component to, or from, its packaging. There are two commonly used types of wire bonding – wedge and ball. Which one is more suitable depends on the substrate, the contact material, the bonding material, and a number of other physical factors. Bonders can be manual or automated, and some can feature pattern recognition software to help speed the bonding process up.

Bonding a wafer to another wafer is a step commonly used when packaging components in an micro or nanoelectrical device. It can help a form new functions in a device, or can ensure mechanical and hermetic encapsulation of devices and electronics. The result is typically irreversible. Common bonding methods include using heat or with an adhesive for thermally sensitive samples.

Annealing is a process that can reduce residual stress in a substrate that has accumulated during prior processes such as deposition.The material is heated to high temperatures and allowed to cool at a controlled rate. This allows the material’s crystal structure to relax into a less intrinsically stressed state, and to settle into a more desirable microstructure as it cools.