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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


WLCSP Assembly options

Views: 1461

#86423

WLCSP Assembly options | 16 March, 2021

I am wondering, I have an application for assembling a 0.4mm WLCSP to a pcb....the solder sphere size is 0.26mm...would you print paste in the normal printing process and then place the device and reflow...or would you use a fluxing station on the pick and place machine to dip flux it and reflow using just gel flux (just using the solder sphere to make the joint...no paste).....anyone any preference to either process ?

reply »

#86424

WLCSP Assembly options | 17 March, 2021

I would recommend flux approach. I have placed tons of these packages. They have plenty of paste on the balls, and tend to short easy when you screen paste. Even if you get the print right, you would still see more voiding compared to using just flux.

reply »

#86426

WLCSP Assembly options | 17 March, 2021

Hello Evtimov, thank you for your reply. I agree with you, using gel flux should be best. Did you use flux dipping station on a pick and place machine, or do it manually ?

reply »

Industry 4.0 Reflow Oven

Non-heated dispensing system