CAPP for Electronics Manufacturing Case Study: Fine Pitch SMT Laser Soldering

Abstract

The trend to high-density packaging in surface mount assembly has highlighted inherent difficulties in the assembly line of these very fine pitch devices. A variety of defects is still common in printed circuit board assembly (PCBA) technology despite all the improvements made, and rework of PCBA is inevitable and performed manually in PCBA manufacturing floors since the cost of each component and PCB itself may be hundreds of dollars. In the last few years, the number of rework stations available on the market has grown considerably including the automated ones, but there has still been no significant reduction in the number of the defects. In electronics manufacturing, rework is defined as the activity that replaces defective components with those that are acceptable such that the populated board performs to the specifications. Increasing product complexity, decreasing component size, and using double sided boards have made rework more difficult and the economic reworking of PCBAs is one of the main problems facing PCB manufacturers. PCBA manufacturing has been relatively improved with fully automated, accurate assembly machines and the use of robots. Although significant improvement in automated rework has also been made by the author, it has been shown that the outcomes of the automated rework line have not produced a high enough level of the reliable yield percentage. The objective of this research project is to make a contribution towards this surface mount rework by creating a Computer Aided Process Planning (CAPP) system of circuit board defects so that the defects that necessitate rework operation can be detected through the electronics manufacturing assembly line. With the development of CAPP tool, the rework will be removed from the PCBA line and PCBA process parameters which cause joint level reliability problems will be troubleshot with the help of the developed system.