Posted in World forum
Electrostatic protection: LED is a semiconductor device, which is sensitive to static electricity. Especially for white, green, blue and purple LED, we should do a good job in preventing static electricity and eliminating static electricity.
1. There are three main ways of generating static electricity:
(1) Friction electrification: In daily life, any two objects of different materials contact and then separate, can produce static electricity. The most common method of generating static electricity is friction electrification. The better the material is, the easier it is to generate electricity by friction. In addition, static electricity can also be generated when any two different substances are separated after contact.
(2) Induction electrification: For conductive materials, because electrons can move freely on their surface, such as in an electric field, because of the same repulsion and the opposite attraction, positive and negative ions will transfer and charge will be generated on their surface.
(3) Conduction: For conductive materials, charge transfer occurs because electrons can move freely on their surfaces, such as contacting charged objects.
2. The harm of static electricity to LED: Particular attention should be paid to the electrostatic hazards to the LED packaging itself.
(1) Because of the heat generated by the instantaneous electric field or current, the LED is partially injured, which shows that the leakage current increases rapidly and can still work, but the brightness decreases (the white light will change color) and the lifetime is damaged.
(2) Because the electric field or current destroys the LED's edge layer, the device can not work (completely destroyed), which is manifested as dead light, which is not on.
3. Elimination measures: In the whole process (production, testing, packaging, etc.), all employees who are in direct contact with LED should take good measures to prevent and eliminate static electricity. The main measures are as follows:
(1) The worktable is anti-static, and the production machine is well grounded.
(2) Static flooring should be installed and grounded in the workshop.
(3) Operators wear anti-static clothes, wear anti-static bracelets, gloves or foot rings.
(4) Antistatic materials are used for packaging.
(5) Grounding measures should be taken by using ion blower and welding electric soldering iron.