1, hot pressure welding
The wire and the welding area are pressure welded together by heating and pressure. The principle is that by heating and adding pressure, the welding zone (such as AI) will undergo plastic deformation and destroy the oxide layer on the pressure welding interface, so as to generate the attraction between atoms to achieve the purpose of "bonding". In addition, the two metal interface is not flat heating pressure can make the upper and lower metal Mosaic each other. This technology is generally used for chip COG on glass plates, such as China RGB COB Strip.
2. Ultrasonic welding
Ultrasonic welding is the energy generated by ultrasonic generator through transducer under the ultra high frequency magnetic field induction, the elastic vibration of the rapid expansion of the cleaver corresponding vibration, at the same time, a certain amount of pressure on the cleaver, so cleaver in under the joint action of these two kinds of force, drive the AI silk metallized layer in the welding area, such as membrane (AI) surface friction quickly, This deformation also destroys the oxide layer at the interface of AI layer, so that the two pure metal surfaces are in close contact with each other to achieve interatomic bonding, thus forming welding. The main welding material is aluminum wire welding head, generally wedge.
3, gold wire welding
Ball welding in lead bonding is the most representative welding technology, because the current semiconductor packaging two, three transistor packaging are using AU wire ball welding. And it is easy to operate, flexible, solid solder joint (diameter of 25UM AU wire welding strength is generally 0.07~0.09N/ point), and no direction, welding speed can be as high as 15 points/second above. Gold wire welding is also called hot (pressure)(super) acoustic welding. The main bonding material for gold (AU) wire welding head is spherical, so it is ball welding.