PCB (FR4 epoxy printed circuit board) open/short defect is problem encountered almost every day to each PCB (printed circuit board) manufacturer. Major PCB manufacturers have been plagued by it in production, quality management. It causes insufficient quantity of shipments and re-making, delivery delays, customer complaints, difficult to solve the problem even by PCB professionals.
Over a long period of accumulation of manufacturing experience, China PCB manufacturer-SYS Tech summed up several reasons and proposed solutions.
Cause analysis of above defect is the cooper substrate is scratched when still exposed, our engineers’ improvement methods category are listed below:
Cause analysis
1.PCB CCL had scratched before imported into ware house.
2.PCB CCL is scratched in CCL cutting process
3.PCB CCL is scratched in mechanical drill process by drilling bit
4.PCB CCL was scratched in process transit in factory
5.After PTH process, improper stacking of plate caused copper foil surface scratched
6. Production plate is scratched by horizontal wash and plating machine/machine.
Improve its methods are:
1. before CCL entering the ware house, IQC inspecting must be carried out to check whether the CCL was scratch, if any was found, IQC should promptly contact the vendor, then make the appropriate handling according to the actual situation.
2. CCL was scratched in the board cutting process, mainly due to hard objects on the feeder table, Thus before operating, must carefully clean the feeder table to ensure smooth table without the presence of any hard objects.
