A Sneak Peek at Some Research from Zestron

As printed circuit boards evolve, they are becoming more densely populated and increasingly complex. This has resulted in increasing performance pressure on PCB cleaning methods and PCB cleaners.

Zestron’s Senior Engineer, Jigar Patel, M.S.Ch.E. recently completed a study examining the impact of different solder mask options on under component cleanliness. Today we thought we’d give you a sneak peek into his study.

The solder mask is necessary for long term reliability of PCBs. But can its presence also impact the PCB cleaning process effectiveness?

Without further ado, here’s your very own peek behind the curtain…

Copper traces and pads are integral to PCB design. In order to protect these from corrosion and oxidation, the PCB is covered by a solder mask. This prevents performance degradation by providing a barrier between soldered joints and other conductive elements on the PCB. As detailed in IPC SM-840D, solder mask materials applied to the printed board substrate shall prevent and/or minimize the formation and adherence of solder balls, solder bridging, solder build-up and physical damage to the printed board substrate. The solder mask material shall help impede electromigration and other forms of detrimental or conductive growth.

The solder mask is necessary for long term reliability of PCBs, but can its presence also impact cleaning process effectiveness? When incorporating a solder mask, the designer can specify the solder mask as either Solder Mask Defined (SMD), Non-Solder Mask Defined (NSMD) or No Solder Mask (NoSM). Although there are design considerations for using either solder mask approach depending upon component details, in general with SMD and NSMD, the component standoff height is slightly less when compared with NoSM which could impact the cleaning process effectiveness.

For this study, the authors wanted to assess the impact of different solder mask options on under component cleanliness…

 

Are you ready to see how the story ends? Join us on September 17th at 1:30pm EDT for a FREE webinar entitled Solder Mask & Low Stand-Off Component Cleaning – A Connection? This informative and exploratory presentation will cover variety of takeaways and findings from this newly completed study.