Authored By:
Jay Soma, Jeffrey Dunlap, Robert Sell
Bill Breault, Christine Fouts
Petroferm Inc., Gurnee, IL USA
Transcript
Batch cleaning of electronic assemblies is popular in all regions of the world and continues to grow due to its flexibility, ease-of-use and economic considerations.
Batch spray-in-air processes tend to dominate the new systems being installed in North America while batch immersion with and without ultrasonics are popular in Asia. In Europe, batch vapor degreasing and co-solvent processes remain quite popular.
Regional preferences, local environmental regulations, economics and availability are some of the factors influencing process choice.
This study was undertaken to compare the relative performance of each of these processes in cleaning flux residues from underneath low stand-off components. Pros and cons of each of these processes are highlighted.
Summary
Batch cleaning of electronic assemblies is popular in all regions of the world and continues to grow due to its flexibility, ease-of-use and economic considerations. Batch spray-in-air processes tend to dominate the new systems being installed in North America while batch immersion with and without ultrasonics are popular in Asia. In Europe, batch vapor degreasing and co-solvent processes remain quite popular. Regional preferences, local environmental regulations, economics and availability are some of the factors influencing process choice. This study was undertaken to compare the relative performance of each of these processes in cleaning flux residues from underneath low stand-off components. Pros and cons
of each of these processes are highlighted.
Conclusions
Batch systems can be utilized to clean a majority of the flux residues, both Sn/Pb and Pb-free from underneath low-stand off components. By adjusting the operating parameters within each batch process ty
pe to optimize conditions for agitation, temperature, wash time and cleaning chemistry, results comparable to inline cleaning can be achieved. As expected, the batch monosolvent is the least aggressive cleaner with fewer operating parameters that can be varied. The batch co-solvent process adds the ability to adjust wash temperatures to some extent. The use of ultrasonics in these systems should improve performance significantly as seen in the monosolvent results. For batch spray-in-air and batch ultrasonics, the greater number of operating parameters to adjust gives these processes greater flexibility.
Initially Published in the IPC Proceedings
|
