3. PCB Defects

Printed circuit board is one of the most important element in the production of an electronic package. Improper fabrication can result in moisture entrapment leading to conductive anodic filament formation. Also, the PTH barrel integrity can be affected if the process control measures are not strictly followed. Moreover, the solderability of the PCBs can be impaired due to the formation of thick intermetallic compound on improper storage of the finished product. In this chapter, the notion of various quality control methods on procurement, process and acceptance related phases has been introduced. The parameters which need to be inspected for screening of PCBs for high-reliability applications have been tabulated. A checklist of the various defects on microsectioning of coupons of PCBs has been presented. This chapter illustrates the defects in PCBs through high-resolution photographic images. The methods for mitigation/elimination of these defects have also been explained. A total of 55 live cases under 18 groups are presented.