The manufacturing process of the LED chip can be roughly divided into several steps such as a wafer processing process (Wafer Fabrication), a wafer needle testing process (Wafer Probe), a packaging process (Initial Test and Final Test), and the like. The wafer processing step and the wafer needle measurement step are the front end steps, and the assembly process and the test process are the back end processes. 1, wafer processing process The main work of this process is to make circuits and electronic components (such as transistors, capacitors, logic switches, etc.) on the wafer. The processing procedure is usually related to the product type and the technology used, but the general basic procedure is to first properly apply the wafer. After cleaning, oxidation and chemical vapor deposition are performed on the surface, and then repeated steps such as coating, exposure, development, etching, ion implantation, and metal sputtering are performed, and finally, several layers of circuits and components are processed and fabricated on the wafer. 2, wafer needle testing process After the previous process, a small grid, ie, a die, is formed on the wafer. Generally, in order to facilitate testing and improve efficiency, the same type and specification of products are produced on the same wafer; Need to make several products of different varieties and specifications. After measuring the electrical characteristics of each die with a probe, and marking the unqualified die, the wafer is cut into individual grains and then electrically characterized. Classification, loading into different trays, and rejecting unqualified grains. 3, the assembly process That is, a single die is fixed on a plastic or ceramic chip base, and some lead terminals etched on the die are connected with the pins protruding from the bottom of the base to be connected to the external circuit board. Finally, cover the plastic cover and seal it with glue. Its purpose is to protect the crystal grains from mechanical scratches or high temperature damage. At this point, we have made an integrated circuit chip (that is, those black or brown that we can see in the computer, rectangular blocks with many pins or leads on both sides or four sides). 4. Test procedure The last process of chip manufacturing is testing. It can be divided into general test and special test. The former is to test the electrical characteristics of the packaged chip under various environments, such as power consumption, running speed and pressure resistance. The tested chips are classified into different grades according to their electrical characteristics. The special test is based on the technical parameters of the customer's special needs, take some chips from the similar parameter specifications and varieties, and do specific tests to see if they can meet the special needs of customers to decide whether they need to design special for customers. chip. Products that have passed the general test are affixed with labels of specifications, models, and date of manufacture, and are packaged and shipped. Chips that fail the test are classified as downgrades or scraps depending on the parameters they reach. 21-75Kva Diesel Generator,Portable Type Diesel Generator,Home Use Diesel Generator,Shanghai Power Generator Set Shanghai Kosta Electric Co., Ltd. , https://www.shkostagenerator.com