Ask LED engineers, what is the difference between COB packaging technology and traditional packaging?

There are two main forms of bare chip technology: one is COB technology, and the other is flip chip technology.

COB technology

COB is to bond bare chips to the interconnection substrate with conductive or non-conductive adhesive, and then wire bond them to realize their electrical connection. If the bare chip is directly exposed to the air, it is easy to be polluted or artificially damaged, which will affect or destroy the function of the chip, so the chip and the bonding wire are encapsulated with glue. People also call this form of packaging soft packaging.

The bare chip encapsulated by COB technology is the chip body and I/O end on the crystal. During soldering, the bare chip is bonded to the PCB by conductive/thermal adhesive. After solidification, metal wires (al or Au) are connected to the I/O bonding area of the chip and the corresponding pads of the PCB by bonding machine under the action of ultrasonic wave and hot pressing. After passing the test, seal the resin adhesive.

Compared with traditional packaging technology, COB technology has the following advantages: low price; Save space; Mature technology. COB technology also has shortcomings, that is, it needs to be equipped with welding machines and packaging machines, and sometimes the speed can't keep up; PCB patches have stricter requirements on the environment; Irreparable, etc.

Cob, a traditional packaging technology, will play an important role in the packaging of portable products.