With the development of SMT chip processing technology (circuit board) and the continuous improvement of SMT assembly density, as well as the thinning of circuit patterns, the finer pitch of SMD, and the enhancement of features such as non-visualization of device pins, SMT chip The quality control of processed products and the corresponding inspection work have brought many new technical difficulties. At the same time, it is also crucial to adopt appropriate testability design methods and detection methods in the SMT process.

　　It is very important to prevent various defects and unqualified hidden dangers from flowing into the next process through effective detection methods in each step of SMT chip processing (circuit board). Therefore, "detection" is also an indispensable and important means in process control. The inspection content of the SMT chip processing factory includes incoming inspection, process inspection and surface assembly board inspection. Wear anti-static gloves and PU coated gloves.

　　Quality problems found during process inspection can be corrected by rework. The rework cost of defective products found in incoming inspection, solder paste printing, and pre-soldering inspection is relatively low, and the impact on the reliability of electronic products is relatively small. However, the rework of defective products after soldering is very different, because rework after soldering requires re-soldering after desoldering, which may damage components and printed circuit boards in addition to man-hours and materials.

　　Since some components are irreversible, such as Flip chip that needs to be underfilled, and BGA and CSP need to be re-balled after repairing, it is more difficult to repair products such as embedded technology and multi-chip stacking, so the rework loss after soldering is large. Anti-static gloves and PU coated gloves are required. It can be seen that process inspection, especially the inspection of the first few processes, can reduce the defect rate and scrap rate, reduce the cost of rework/rework, and at the same time, it can also prevent the occurrence of hidden quality risks from the source as soon as possible through defect analysis.

　　Final inspection of surface mount boards is equally important. How to ensure that qualified and reliable products are delivered to users is the key to winning in the market competition. There are many final inspection items, including appearance inspection, component position, model, polarity inspection, solder joint inspection, electrical performance and reliability inspection, etc.

　　Detection is an important link to ensure the reliability of SMT. The content of SMT inspection technology is very rich, and the basic content includes: testability design; raw material incoming inspection; process inspection and component inspection after assembly.

　　The testability design is mainly the testability design of the PCB circuit in the PCB patch processing circuit design stage, which includes the test circuit, the test pad, the test point distribution, and the testability design of the test instrument.

　　The inspection of incoming raw materials includes the inspection of PCB patch processing and components, as well as the inspection of all SMT assembly process materials such as solder paste and flux.

　　Process inspection includes process quality inspection of printing, patch, welding, cleaning and other processes. Component testing includes component appearance testing, solder joint testing, component performance testing, and functional testing.

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