In general, the LED epitaxial production after completion of her main performance has already set, chip manufacturing does not produce the 甞 nuclear nature to change, but in the process of coating, alloying inappropriate bad conditions can cause some electrical parameters. For example, low or high alloying temperature will cause poor ohmic contact, which is the main cause of high positive pressure drop VF in chip manufacturing. After cutting, if some corrosion process is carried out on the edge of the chip, it will be helpful to improve the reverse leakage of the chip. This is because after cutting with a diamond grinding wheel blade, there will be more debris powder left on the edge of the chip. If these particles stick to the PN junction of LED chip, it will cause electricity leakage and even breakdown phenomenon. In addition, if the chip surface photoresist stripping is not clean, it will cause the front welding line difficult and virtual welding, etc. If it is a reverse side, it will also cause a high pressure drop. In the process of chip production, the light intensity can be improved by surface coarsening and trapezoidal structure.