LED manufacturing process, the main anti-oxidation products for the chip manufacturing process of semiconductor materials. That is, metal circuit frame storage, metal bracket, etc., the main materials to gold, silver, copper, nickel, aluminum and semiconductor materials.
Copper is most likely to oxidize in these materials, so it is generally coated with a layer of protective material on the copper outer layer. Such as gold, silver, nickel and so on. In the LED industry, silver plating materials are more common, Tama Bank in the conventional state of chemical properties stable, with water and air oxygen very little chemical reaction, but encountered hydrogen sulfide, oxygen compounds, ultraviolet radiation, acid, alkali, salt material action is very prone to chemical reactions, the performance of the silver layer surface yellowing and gradually become black-brown.
The factors affecting the anti-oxidation of metal stents are: humidity, storage time, coating quality (thickness) and so on. Common applications in the industry are regular gold and silver plating, humidity stable 30%RH below, time does not exceed 1 months. Metal frame generally to copper, nickel as the main material, it is easier to oxidize, and more afraid of dust, so the industry common storage method is placed in theNitrogen cabinetsInside and in low-humidity cabinets.
LED after opening the packaging should be welded within 12 hours, the remaining non-welded LEDS should be stored in moisture-proof bags, such as sealed with moisture absorption containers. It is recommended that the remaining LEDS be placed back in the original packaging. LED electrode, bracket, heat layer are all copper material and surface electroplating silver. Silver may be affected by contamination in a corrosive physical environment. Therefore, avoid storing in an environment that causes LED corrosion, loss of luster, and discoloration of the bracket, LED corrosion or discoloration may reduce solderability or affect optical properties. LED exposure to high temperatures in corrosive environments is more likely to accelerate LED corrosion. At the same time, avoid the rapid transfer of LEDS from different ambient temperatures, especially note that this may cause shrinkage in high humidity environments. But at present, such a common storage scheme is faced with a variety of problems: low-humidity storage cabinets to lower-end civilian mainly, slow speed, humidity fluctuations and errors, often open and close humidity is difficult to drop down, so prone to subtle oxidation phenomenon.
Nitrogen cabinets are also known as nitrogen drying cabinets, in the LED packaging process, can play a moisture-proof anti-oxidation effect. Provincial energy nitrogen cabinet is the use of nitrogen control system, the use of humidity to control nitrogen energy, automatic control of nitrogen filling, in order to achieve effective protection of goods and energy saving effect. When the humidity in the box reaches the set value, the system will automatically cut off the nitrogen supply, and when the set value is exceeded, the system will intelligently open the nitrogen supply. Therefore, nitrogen drying cabinets in the LED manufacturing process for the production of adverse rates and product quality plays a very important role.