Improving Solder Paste Printing with Squircle Aperture Designs

This document is a technical report that discusses the benefits of squircle aperture designs in solder paste printing. It defines the squircle shape as a combination of square and circle features, which enhances both solder paste volume and transfer efficiency in surface mount technology (SMT) stencil design. The report outlines the properties of circle and square apertures, highlighting their respective advantages and limitations. It presents experimental comparisons conducted at AIM's applications laboratory, which tested various aperture shapes for transfer efficiency and deposit volumes. The findings indicate that squircle apertures consistently achieve the highest transfer rates while maintaining low variation, outperforming both circle and square designs. The report concludes by noting the need for further research to explore the squircle's applications in different assembly conditions and materials, while also suggesting the potential benefits of using nanocoatings on stencils. Overall, the report provides a comprehensive examination of squircle designs as a promising enhancement to solder paste printing processes.