Hot Air Level: An Endangered Species

摘要

The topic of hot air solder leveling (HASL) has come up a handful of times recently and so the motivation for this column. An OEM currently using HASL but with advances in board designs had observed last month that the ball grid array patterns were not covering properly. They also experienced instances when component placement was off due to the uneven nature of the HASL deposit. They requested some information on "alternate finishes." The call came about 10 to 15 years later than I expected. A few days later, I visited a North American plating shop that finishes the majority of its products with various electrolytic and electroless nickel/gold plating. A "good percentage" of its product remains HASL, and they asked when HASL would go away. The process is not a favorite among the operators.