Stencil Process Solutions

Our stencil engineers are committed to solving process issues for our customers. This is done through either a design solution or a change in the stencil technology; sometimes both. Combining an understanding of your PCB layout coupled with our knowledge of the printing process and materials used yields the best solutions. See below videos on the aperture filling with solder paste and the release of the stencil.

Courtesy of https://smt.asmpt.com/en/

Methodology & Design

QFN Aperture Design Solution.pdf

Aperture design is where we spend the most time solving printing problems. See the link above for QFN thermal pads aperture case study. We have an abundant amount of experience on implementing aperture designs which will lead to a perfect print process. Aperture designs combined with step technology, fine grain or nickel metal, and other post cutting processes to make sure each stencil delivers the best quality. For example, the design below of a 4 ball micro-BGA, we were able to eliminate insufficients by adding a tear drop design edit to give the ball more paste without bridging.

Oxygen Cutting

Years ago we underwent a study of what cover gases produce the best cut quality. When we started the study, it was assumed that inert gases like Nitrogen or others would give us cleaner smoother walls. As we went through the testing, we found that Pure Oxygen, produced significantly smoother cuts, with out any slag or needs to polish. Upon further investigation using an Electron microscope, or a SEM, Nextek Inc, was able to see the differences. So were our customers’. We would provide blind tests, stencil cut in Air, and then randomly ship an Oxygen cut stencil. Every time, our customers could see the differences in the print quality. Since around 2014 AGI made the investment to outfit our facilities with Oxygen. All of our stencils are cut using this cover gas. See the results for yourself!

SEM image courtesy of Nextek Inc, www.NextekInc.com