Surface mount LEDs appeared in the early 1980s in response to smaller packages and factory automation. The main factor is that the first problem faced by surface adhesive LEDs is that the solder reflow step under high-temperature infrared cannot be completed. The specific heat of LEDs is lower than that of ICs, and when the temperature rises, not only will the brightness decrease, but it will also accelerate the deterioration of the component when it exceeds 100 degrees Celsius. The resin used in LED encapsulation absorbs moisture, and when these water molecules vaporize rapidly, cracks will occur in the original encapsulation resin, affecting product efficiency.