1. The production process of packaging enterprises is not complete, and the inspection methods of incoming materials are backward. The direct cause of LED dead lights is generally LEDs packaged in bracket rows. The bracket rows are made of copper or iron metal materials and stamped by precision molds. Expensive, the cost is naturally high. Affected by the fierce competition in the market, in order to reduce the manufacturing cost, most of the market uses cold-rolled low-carbon steel to bring stamping LED brackets, and the iron brackets must be silver-plated, and there are two silver-plated The first is to prevent oxidation and rust, and the second is to facilitate welding. The plating quality of the bracket row is very critical, which is related to the life of the LED. The disposal before electroplating should be carried out in strict accordance with the operating procedures. Be meticulous, control the current during electroplating, and control the thickness of the silver-plated layer. If the coating is too thick, the cost will be high, and if the coating is too thin, the quality will be affected. Because the general LED packaging companies do not have the ability to inspect the plating quality of the bracket row, this gives some electroplating companies an opportunity to thin the silver plating layer of the plated bracket row and reduce the cost. There is a lack of inspection methods, and there is no instrument to detect the thickness and fastness of the plating layer of the bracket row, so it is easier to get away with it.

  Some bracket drains rust after a few months in the warehouse not to mention the poor quality of the visible plating used. Products made with such a bracket row are definitely not used for a long time, let alone 30,000-50,000 hours, 10,000 hours are a problem. The reason is very simple. Every year there is a period of southerly wind. In such weather, the humidity in the air is high, and it is easy to cause embroidery of metal parts with poor electroplating, which makes LED components fail. Even if the LED is encapsulated, the silver-plated layer will be too thin and the adhesion will not be strong, and the solder joint will be separated from the bracket, resulting in a dead lamp phenomenon. This is when the well-used light does not light up. In fact, the internal solder joints are separated from the bracket.

2. Each process in the packaging process must be carefully operated. Any negligence in any link is the cause of the dead light. The point and solid crystal process, the silver glue (for single solder joint chips) is too much or too little. Too much glue It will return to the gold pad of the chip, causing a short circuit, and the chip will not stick firmly. The same is true for the double-soldered chip insulation glue. If there is too much insulation glue, it will return to the gold pad of the chip, resulting in virtual welding during soldering and a dead light. A few chips will not stick well, so the glue must be just right, neither too much nor too little. The welding process is also very critical. The four parameters of the gold wire ball welding machine, pressure, time, temperature, and power, must be properly coordinated. In addition to the fixed time, the other three parameters are adjustable. The adjustment of the pressure should be moderate, and the pressure is easy to Crush the chip, if it is too small, it is easy to solder. The welding temperature is generally adjusted at 280 ℃. The adjustment of power refers to the adjustment of ultrasonic power. Too large or too small is not good. The degree is moderate. In short, the adjustment of various parameters of the gold wire ball welding machine is based on the welding Data, with a spring torque tester to detect ≥ 6 grams, is qualified.

  Every year, the parameters of the gold wire ball bonding machine are inspected and calibrated to ensure that the welding parameters are in the best state. In addition, there are also requirements for the arc of the welding wire. The arc height of a single-solder chip is 1.5-2 chip thicknesses, and the arc height of a double-solder chip is 2-3 chip thicknesses. The arc height will also cause LED quality problems, and the arc height is too high. If the arc height is too low, it is easy to cause the dead lamp phenomenon during welding. If the arc height is too large, the resistance to current impact is poor.