Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

vacuum reflow

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vacuum reflow | 13 May, 2021

Hi, are there any component types that are not suitable for vacuum reflow ? I've had one customer use his vacuum vapour phase reflow system on a pcb, and on 10% of the hermetically sealed accelerometers devices. the lids have popped off... Thanks Graham

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vacuum reflow | 14 May, 2021

I've only used vacuum reflow on LED boards but I have heard that Vacuum may need to be reduced depending on components. I can't find the source at the moment but it was a study done by Heller I believe.

I would experiment with different levels of vacuum. If using 120 Torr and getting defects try adjusting to 90 Torr and see if results are better.

Vacuum reflow is great but it can take a long time to tune in a good profile.

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vacuum reflow | 14 May, 2021

Agree with WiIIR and also can recommend to play with vaccum pump RPM . Slower vacuum increasing have help me to resolve one problem caused by the vacuum (it was solder splash from BGA balls, but the reason can be similar to your case).

Also check if the vacuum is really necessary for this assembly. If there is no BGA, BTC with strong requirement for thermal pad coverage, or oxidised leads, maybe you can just turn the vacuum off.

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