Have you ever found yourself knowing where you want to go, but not sure how to get there? This can be frustrating and time consuming if not impossible without a map. It can be the same when introducing a solder preform into your process. You know what you hope to achieve by adding a preform, but where do you start to design it? Whether you’re thinking of designing a solder preform into your build or using one to replace paste, the approach is generally the same.
· The solder volume should be sufficient to meet the desired reliability and performance criteria.
· The geometric constraint is normally derived by the component being soldered and desired bond line thickness
· The soldering temperature of the alloy should not be high enough to damage components, but robust enough to withstand the max operating temperature.
· If step soldering, then the melting temperature of the alloy needs to fall into the reflow hierarchy you have designed for your process.
· Surface metallization should be compatible with the solder used to make the joint.
Although this is a simplified list, it does offer a starting point. For more information follow this link, Practical suggestions for solder preform design
If this doesn’t get you there, feel free to contact me directly 315-853-4900 ext. 2106