Solder paste in SMT: a training perspective

This paper is written for the trainer or supervisor responsible for training operators of an inhouse printing process. It provides a general outline introducing each of the printing-related topics in a logical sequence. The trainer can use this outline to customize a "local" training program, adapting each topic to in-house equipment and operations, and enhancing each topic with his/her expertise. It begins with an introduction to solder paste, its contents and types, and solder paste quality tests. Screen printing topics address the stencil, its fabrication, and application of solder paste in the screen printer. Key stencil-related terms are discussed, as are key elements ofthe screen printer, printer adjustments, and their impact on the print results. It concludes with discussion of the paste inspection process, key inspection criteria, and SPC data collection