Epitaxial wafer→cleaning→plating transparent electrode layer→transparent electrode pattern lithography→corrosion→debonding→platform pattern lithography→dry etching→degraction→annealing→SiO2 deposition→window pattern lithography→SiO2 corrosion→degglomerate→ N-pole pattern lithography → pre-cleaning → coating → stripping → annealing → P-pole pattern lithography → coating → stripping → grinding → cutting → chip → finished product testing. In fact, the production process of the epitaxial wafer is very complicated. After the epitaxial wafer is finished, the next step is to make the electrode (P pole, N pole) of the LED epitaxial wafer , and then start cutting the LED epitaxial wafer with a laser machine (previously cutting LED epitaxial wafers are mainly made of diamond knives. After being fabricated into chips, nine points are taken at different positions on the wafer for parameter testing. 　 1. Test the voltage, wavelength and brightness mainly. The wafer that meets the normal shipping standard parameters will continue to do the next step. If the nine-point test does not meet the relevant requirements, the wafer is placed on one side. deal with. 2. After the wafer is cut into chips, 100% of the visual inspection (VI/VC) is performed by the operator using a microscope magnified 30 times. 3. The chip is then fully automated, selected, tested, and classified using a fully automated sorter based on different voltage, wavelength, and brightness prediction parameters. 4. Finally, the LED chip is inspected (VC) and labeled. The chip area should be at the center of the blue film. There are up to 5,000 chips on the blue film, but the number of chips on each blue film must be no less than 1000. The chip type, batch number, quantity and photoelectric measurement statistics are recorded on the label. Attached to the back of the glossy paper. The chip on the blue film will be the same as the first visual inspection standard, ensuring that the chips are neatly arranged and of good quality. This makes LED chips (currently known as square chips on the market). In the LED chip manufacturing process, some defective or electrode-worn chips are separated, these are the latter crystals. At this time, there are some wafers on the blue film that do not meet the normal shipping requirements. Become a side piece or a piece of hair. The chip is then fully automated, selected, tested, and classified using a fully automated sorter based on different voltage, wavelength, and brightness prediction parameters. 1, LED chip test Microscopic examination: Whether there is mechanical damage on the surface of the material and whether the size and electrode size of the lockhill chip can match the process requirements. 2, LED expansion Since the LED chips are still arranged with a tight pitch (about 0.1 mm) after dicing, it is disadvantageous for the operation of the post process. The film of the bonded chip is expanded by a film expander to stretch the pitch of the LED chip to about 0.6 mm. It can also be manually expanded, but it is easy to cause problems such as chip dropping and waste. 3, LED dispensing Silver glue or insulating glue on the corresponding position of the LED bracket. Regarding the GaAs or SiC conductive substrate, a red, yellow, and yellow-green chip having a back electrode is used, and silver paste is used. Regarding the blue and green LED chips of the sapphire insulating substrate, an insulating glue is used to fix the chip. The difficulty of the process lies in the control of the amount of dispensing, and there are specific technical requirements in the height of the colloid and the position of dispensing. Because silver glue and insulating glue have strict requirements in storage and application, the wake-up, mixing and application time of silver glue are all matters that must be paid attention to in the process. 4, LED preparation glue In contrast to dispensing, the glue is applied to the back electrode of the LED with a glue machine, and then the LED with silver glue on the back is mounted on the LED holder. The efficiency of preparing glue is much higher than that of dispensing, but not all products are practically prepared. Road Light,Double Arms Road Light,Off Road Lights,Round Road Light Yangzhou Heli Photoelectric Co., Ltd. , https://www.heli-eee.com