Under normal circumstances, the electronic products we use are designed by PCB plus various capacitors, resistors and other electronic components according to the designed circuit diagram, so all kinds of electrical appliances need various SMT chip processing technology to process. SMT is Surface Mount Technology (Surface Mount Technology) (abbreviation of Surface Mounted Technology), which is currently the most popular technology and process in the electronics assembly industry.
To put it simply, the components of the basic SMT process are as follows: Solder paste printing --> parts mounting --> reflow soldering --> AOI optical inspection --> maintenance --> sub-board.
The following are the details: The basic elements of the SMT process include: silk screen (or dispensing), placement (curing), reflow soldering, cleaning, testing, and repair
1. Silk screen printing: Its function is to leak solder paste or patch glue onto the pads of the PCB to prepare for the soldering of components. The equipment used is a screen printing machine (screen printing machine), which is located at the forefront of the SMT production line.
2. Glue dispensing: It is to drop glue onto the fixed position of the PCB board, and its main function is to fix the components to the PCB board. The equipment used is a glue dispenser, which is located at the forefront of the SMT production line or behind the testing equipment.
3. Mounting: Its function is to accurately install the surface mount components to the fixed position of the PCB. The equipment used is a placement machine, which is located behind the screen printing machine in the SMT production line.
4. Curing: Its function is to melt the adhesive, so that the surface mount components and the PCB board are firmly bonded together. The equipment used is a curing oven, which is located behind the placement machine in the SMT production line.
5. Reflow soldering: Its function is to melt the solder paste, so that the surface mount components and the PCB board are firmly bonded together. The equipment used is a reflow oven, which is located behind the placement machine in the SMT production line.
6. Cleaning: Its function is to remove the welding residues harmful to human body on the assembled PCB board, such as flux. The equipment used is a washing machine, and the location may not be fixed, online or offline.
7. Inspection: Its function is to inspect the welding quality and assembly quality of the assembled PCB board. The equipment used includes magnifying glass, microscope, online tester (ICT), flying probe tester, automatic optical inspection (AOI), X-RAY inspection system, functional tester, etc. The location can be configured in a suitable place on the production line according to the needs of detection.
8. Rework: Its function is to rework the PCB board that has failed. The tools used are soldering iron, rework station, etc. Configured anywhere in the production line.
It is precisely because of the complexity of the process flow of SMT chip processing that there have been many factories specializing in SMT chip processing. Thanks to the vigorous development of the electronics industry in Dongguan, SMT chip processing has achieved great success. The prosperity of an industry.