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LED board chip (COB) packaging process

From: Data:28/08/2016

LED board chip on board (chip, COB) packaging process first is basal surface with a conductive epoxy resin (usually silver doped particles of epoxy resin) overlay wafer placed points, then the silicon indirect placed under the surface of the substrate, the heat treatment to the wafer firmly fixed is basal line, then use wire welding method is between the wafer and the substrate indirect establish electrical connections. The seal and open process is as follows:

the first step: expanded crystal by expanding Chi machine manufacturers to provide zero Chi LED wafer thin films with uniform expansion, pull open the attached to destroy is thin film surface close to the display of the LED grain, easy thorn crystal. The second step:

gum will expand good crystal crystal expansion ring is not blowing a good gum machine silver paste layer on the surface of the back of silver paste. Silver paste. Suitable for loose LED chip. By dispensing the appropriate amount of silver points are on the printed circuit board PCB.

third step: into the thorn frame will be prepared to prepare the silver paste of the expansion ring into the thorn frame outside, by the operator under the microscope will be LED chip with thorn PCB printing on the printed circuit board. the fifth step: the microchips dispenser is the printed circuit board PCB IC who put the right amount of red gum (or vinyl), then anti electrostatic equipment (vacuum suction pen or female) to IC bare chip placed exactly on the red plastic or vinyl.

sixth step: the drying will stick to the naked piece into the heat circulation oven outside the large flat heating plate on the thermostatic static for some time, but also to the natural curing (a longer time).

seventh step: bonding (line) using aluminum wire bonding machine will chip (LED grain or IC chip) to take the PCB board on the bonding pad of aluminum wire to bridge, that is, the COB of the internal wire welding. Step 9: dispensing by dispensing AB glue will prepare the appropriate locations to the state set of grain on the LED IC is used black rubber seal and open, and according to customer requirements for the appearance of seal and open.

tenth step: curing will seal the PCB printed circuit board into the thermal cycle oven outside the constant temperature, according to the requirements can be set different drying time.

eleventh step: after the test will seal a good PCB printed circuit board and then use the common testing tools for electrical performance testing, the distinction between good or bad. With the progress of science and technology, the package has aluminum substrate COB package, COB ceramic COB package, aluminum substrate MCOB package, etc..