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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Bake out CCA

Views: 1135

E.K.

#46517

Bake out CCA | 5 January, 2007

I am using PWB material Rogers 6002 High Frequency Laminate. The PWBs are assembled. They were washed and will require a bake out. Some people say, no bake out is required for the material. I am getting different reads in test if the CCAs are not baked to remove the moisture. Can anyone tell me the approx. temp and time? This is a single sided CCA.

reply »

Mike F

#46550

Bake out CCA | 8 January, 2007

Normally someone would have replied to tell you to do a search of the archives. I've read at least 4 or 5 different threads dealing with baking out PWB's, but none were for this special material.

First, have you contacted the manufacturer of the PWB's and asked them for a profile?

Have you checked the data sheets for the parts to be sure they are all sealed and haven't absorbed any of the cleaning solution? How high a temperature can they be exposed to? Can they go to 80C, or to 105C ?

If you can't get the info above, I would suggest a nice slow ramp up to temperature. If you can use a temp chamber that has an exhaust to get rid of the moisture you would be in better shape. Consider a couple of hours at 50C, then a couple at 70C, then a couple at 80C, and a nice slow cool down. Then see what your test results are. Do one board by itself and see if you get any warping. The Rogers material boards I've used were bonded to an aluminum plate, so do a nice slow ramp up and down and hope to avoid any thermal mismatch and warping. These were a different Rogers material, but I think they were a lot closer to what you have than FR4 is.

I don't recommend going straight up to 100C, a slow ramp with a soak at 80 or 90C in a circulating temp chamber will allow for most of the moisture to come out slowly.

Good luck, Mike

reply »

JTAG Live PCB Debug Software

Heller Industries Mark 5获得了 2015年中国SMT远见奖 - 回焊炉领域