What is the process of wire bonding?
Wire bonding is a solid phase welding process, where the two metallic materials (wire and pad surface) are brought into intimate contact. Once the surfaces are in intimate contact, electron sharing or interdiffusion of atoms takes place, resulting in the formation of wirebond.
What is the purpose of wire bond?
Wire bonding is the process of creating electrical interconnections between semiconductors (or other integrated circuits) and silicon chips using bonding wires, which are fine wires made of materials such as gold and aluminium. The two most common processes are gold ball bonding and aluminium wedge bonding.
What is wire bond package?
Wire bonding forms an interconnection between a chip to a substrate, substrate to a substrate, or substrate to a package. Wire bonding is generally considered the most cost-effective and flexible interconnect technology, and is used to assemble the vast majority of semiconductor packages today.
How do you bond aluminum wire?
Aluminum wire bonding is pure friction welding. Two pure metals are pressed together using a specific amount of pressure and are friction welded with ultrasonic oscillation that is generated by a transducer.
How can we optimize the wire bond process?
Optimizing a wire bond process begins with a clear understanding of the bonding equipment, machine set-up, the response variables involved, and their relationship to one another. Surface cleanliness and bond pad metallurgy is critical.
What do you need to know about wire bonding?
The Wire Bond Process. Wire bonding is an electrical interconnection technique using thin wire and a combination of heat, pressure and/or ultrasonic energy. Wire bonding is a solid phase welding process, where the two metallic materials (wire and pad surface) are brought into intimate contact.
How does wire bonding occur in solid phase?
Wire bonding is a solid phase welding process, where the two metallic materials (wire and pad surface) are brought into intimate contact. Once the surfaces are in intimate contact, electron sharing or interdiffusion of atoms takes place, resulting in the formation of a bond.
What causes a void in a wire bond?
Voiding is generally caused by unequal diffusivities exhibited by the different metals used in the wire bond, a phenomenon known as ‘Kirkendall Effect.’ In gold ball bonding, for example, the rates of diffusion of gold atoms from the gold ball into the aluminum bond pad and the aluminum atoms from the bond pad into the gold ball bond are unequal.
