This course will address advanced problem solving of printed wiring board defects. Some defects, such as interconnect separation, delamination, wedge voids, plating folds, micro-voids, surface pitting, and hole wall pull-away, carry significant costs. Many are difficult to solve because the root cause may not be readily apparent, and multiple factors may contribute. This course will explore the most intricate of these factors and how the interrelationship of up- and downstream processes contribute to scrap product. What effect does drilling have on hole wall quality and the subsequent metallization process? Participants will learn how to recognize problems like this and take corrective action. The course will explore a myriad of electrodeposition defects, such as mouse bites, pitting, and domed or crown plating. Solderability and assembly-related issues such as outgassing, black pad, creep corrosion and blow holes will also be discussed. The course will conclude with a discussion on imaging, including liquid-photoimageable solder masks. Strategies to solve solder mask peeling, poor circuit trace coverage, skips, bubbles, and poor adhesion in nickel gold plating will be discussed. Solder mask equipment and its effect on solder mask quality will also be explored. In addition, over 200 images of defects will be presented.
Attendees will learn how to recognize and solve lamination and other multilayer-related defects; electrodeposition defects: mouse bites, pitting, nodules, crown or dome plating, dog bone defects; copper plating reliability; how to improve plating distribution and throwing power; metallization: microvoids/voiding, interconnect separation, hole wall pull away, and assembly issues; black pad phenomenon: new details on its cause and how to eliminate it; imaging: defects, surface preparation, solder mask issues and defects, process control. Also covered will be other final finish-related defects: creep corrosion, champagne bubble effect, solder mask interfacial attack. Participants should have some knowledge of the PCB fabrication process. This course will directly benefit those involved in printed circuit board fabrication and assembly. In addition, PCB end-users and designers will gain significant knowledge about PCB-related defects.