How To Eliminate Voiding On SMT Devices

What about your solder paste application?

If, by "voids" you mean that the solder doesn't cover the entire area it should, it may be either too little solder, insufficient flux - or contaminated surfaces that don't allow the solder to flow, or excessive solder mask, or inadequate temperatures. Have you perhaps changed to a RoHS solder but not changed your other processes (cleaning, fluxing, temp profiles) to match? Or have you perhaps changed top RoHS components but not changed your solder?

thanks for the reply, we tried adding paste and flux but still it doesnt work. Currently, we are now working on contamination, excessive solder mask and also profile.

another is that, sometimes voids are minimal and sometimes its too high. we are now setting up a new profiler and i hope this will help.

Also, is your paste consistency appropriate for you reflow profile?

nikko

Have you worked through any of the suggestions? bhankii's reply covered quite a bit, any luck?

Do you have some pictures, the tinning could have wetting issues, paste, flux, temp, contamination, etc.

Once had a bridging issue, turned out the board manufacture was leaving a fine copper dust from trace cutting that wicked out the solder off the pad. Found it by microscope looking for something else.

Could also have your paste distributor trouble shoot it for you.

2 cents from

Brad