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Light-emitting diode (LED) is a solid-state semiconductor device that can directly convert electricity into light. The heart of an LED is a semiconductor chip with one end attached to an LED bracket as negative electrode, and the other end connected to the positive electrode of the power supply, the entire chip is encapsulated in epoxy resin.

LED bracket is a base for LED beads before encapsulation. Based on the LED bracket, the chip is fixed in, the positive and negative electrodes are soldered, and then encapsulated into an LED bracket with encapsulant and packaging glue, usually made of copper, also iron, aluminum, and ceramics, etc. LED brackets generally include through-hole LED brackets, piranha LED brackets, SMD LED brackets, and high-power LED brackets. Specialty chemicals for LED electronics refer to fine chemical materials supporting LED bracket plating.