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Opening and short circuit of PCB lines are problems that every PCB manufacturer will encounter almost every day. It has been plagued by production and quality management personnel. The problems caused by the lack of quantity of shipments, such as replenishment, delivery delay and customer complaints, are relatively difficult to solve. I have accumulated some experience in improving the open and short circuit of PCB. Now I have written a summary for the peers'comments on PCB manufacturing. I hope the peers who handle the production and quality of PCB can serve as a reference.

　　Let's first summarize the main reasons for the formation of PCB open circuit as follows:

　　Opening-up for the formation of exposed substrates:
　　1. There are scratches before the copper clad laminate is put into storage.

　　2. Copper clad sheet is scratched in the course of material preparation.

　　3. Copper clad plate was scratched by drill bit while drilling.

　　4. Copper clad laminate was scratched during transshipment.

　　5. The copper foil on the surface was damaged due to improper operation when stacking the plate after sinking.

　　6. The copper foil on the surface of the production plate is scratched when it passes the level machine.

The article originated from Jiangmen single-sided and double-sided circuit boards. http://m.jzfwq.com/