MRSI’s capabilities in fluxless Au/Sn soldering applications
Fluxless soldering, especially with 80/20 Au/Sn ribbon and preforms, is a critical process in advanced electronic packaging where reliability and cleanliness are paramount. While soldering without flux is widely considered difficult, MRSI has distinguished itself as a leader in enabling efficient, repeatable, and high-quality fluxless Au/Sn soldering through its innovative equipment and process control expertise.
Why fluxless Au/Sn soldering is challenging
Typically, flux is used in soldering to clean metal surfaces by removing oxides and to prevent re-oxidation, thus ensuring strong and reliable joints. Gold is resistant to tarnish and should be ideal for fluxless processing, but in practice, most soldering involves gold-plated surfaces rather than pure gold. The underlying base metal—often nickel—oxidizes readily, complicating the process. Without proper protection and oxide removal, solder joints can fail.
MRSI’s process expertise: controlled atmosphere soldering
MRSI’s systems are engineered to address these challenges head-on. By leveraging precisely controlled atmospheres—most commonly a nitrogen and hydrogen mix—MRSI’s equipment effectively replaces traditional liquid flux with “forming gas.” Nitrogen prevents re-oxidation, while hydrogen rapidly reduces and removes oxides, ensuring reliable wetting and joint formation even on nickel surfaces.
MRSI’s eutectic chambers and reflow tools allow for fine-tuned hydrogen concentrations, typically between 5-10%, to optimize both safety and process speed. This balance is crucial, as too little hydrogen slows oxide removal, while higher concentrations demand robust safety features. MRSI’s automated systems ensure consistent heat transfer and temperature profiles, typically operating between 250-350°C for optimal oxide reduction and joint integrity.
Precision and cleanliness: MRSI’s manufacturing advantage
A fluxless soldering process demands absolute cleanliness and precise handling, as surface contaminants can compromise joint quality. MRSI’s equipment integrates handling solutions and process controls that minimize contamination risk during preform placement and soldering, preserving the integrity of Au/Sn joints. This attention to detail supports customers in fields where reliability cannot be compromised, such as aerospace, defense, and high-end photonics.
MRSI also partners with top-tier suppliers, ensuring that Au/Sn preforms maintain strict thickness tolerances. Their process automation prevents handling-induced contamination and guarantees that every joint meets stringent specifications.
Choosing MRSI: quality, reliability, and application expertise
When it comes to fluxless Au/Sn soldering, MRSI’s strengths lie in its holistic approach: advanced atmosphere control, precision temperature management, contamination prevention, and supplier quality assurance. Customers can trust MRSI to deliver robust, repeatable solder joints that meet the demands of today’s most challenging electronic applications.
For organizations seeking to push the envelope in high-reliability packaging, MRSI’s expertise and technology make it the partner of choice for fluxless Au/Sn soldering solutions. Contact us today.