Eutectic crystal welding process for LED wafers

Abstract

The invention discloses an eutectic crystal welding process for LED wafers, which comprises the following steps: the step of dot printing of soldering flux, namely dot printing of soldering flux is performed in a welding position on a to-be-welded support; the step of wafer settling, namely wafers to be welded are settled in the welding position on which dot printing of soldering flux is performed; the step of impulse heating, namely an impulse current heating device is used for allowing impulse current to pass through, heating from the top down can be performed on the wafers, meanwhile, a constant temperature heating device positioned inside a welding base is used for constant temperature heating to the support from the bottom up, so as to enable the support and the wafers to be fixed and bonded after eutectic crystal resolution; and the step of nitrogen cooling, namely, a nitrogen cooling device is used for jetting nitrogen to LED wafers after heat welding, so as to enable the LED wafers to be cooled to a normal temperature. The eutectic crystal welding process for LED wafers, provided by the invention, has the advantages that the heating speed is fast, the welding accuracy is high, the LED wafers after being welded by the process have better thermal conductivity, and the effect of lowering the thermal resisting effect can be reached.

Description

technical field [0001] The invention relates to LED chip package manufacturing technology, in particular to an LED chip eutectic welding process. Background technique [0002] Eutectic soldering technology has a wide range of applications in the electronic packaging industry, such as bonding of chips and substrates, bonding of substrates and shells, capping of shells, etc. Compared with traditional epoxy conductive adhesive bonding, eutectic bonding has the advantages of high thermal conductivity, low thermal resistance, fast heat transfer, strong reliability, and high bonding strength. It is suitable for chips and semiconductors in high-frequency and semiconductor devices. Mutual adhesion of substrate, substrate and shell. [0003] With the rapid development of LED technology, LED chip packaging is increasingly developing in the direction of high power and integration, and LED chips require much higher soldering process than low-power LED chips. The traditional silver glue...

AI Technical Summary

Problems solved by technology

[0004] However, since the eutectic melting point of the LED chip is above 300°C, and the eutectic soldering process of the LED chip in the prior art is generally heated by a hot air reflow furnace, the heating speed of this heating method is slow, and the maximum temperature that can be achieved by heating is relatively low.

In addition, there is also a scheme using infrared welding technology in the prior art. Although this scheme has the advantages of convenient control of the heat source and easy control of the heating temperature rise rate, it also has many disadvantages, such as more photosensitive points will be covered, and more Less unified heating, different components and PCB quality will affect the heating effect, large temperature difference, etc.