Abstract
The present disclosure describes reducing solder joint defects, specifically head-in-pillow (HIP) joints, during the assembly of printed circuit boards (PCBs). As electronic components, such as ball grid arrays, increase in size, thermal warpage can cause temporary separations between the component and the circuit board during the reflow process. If the solder surfaces oxidize while separated, they may fail to merge properly when they eventually come back into contact during the cooling phase. By introducing an active nitrogen flow into the cooling zone of a reflow oven, the oxygen concentration can be maintained at very low levels. The controlled environment limits the oxidation of the solder surfaces, increasing the likelihood that the solder materials will successfully coalesce and form a proper electrical and mechanical connection before fully solidifying.
Keywords: Printed Circuit Board, Reflow Oven, Head-in-Pillow, Oxidation, Nitrogen Flow, Cooling Zone, Solder Coalescence.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
N/A and , "Reducing HIP Joints by Limiting O2 ppm in Cooling Zones of SMT Reflow Oven by Adding N2 Flow and Control", Technical Disclosure Commons, ()
https://www.tdcommons.org/dpubs_series/10886