Hi CP,
From a PCB manufacturing side, all of our product is Lead free / RoHs compliant if it has a surface finish other than Hot Air.
To be ROHS compliant and Able to with stand Lead Free Assembly, this is where the board house would need to switch to a Material with a Higher Td. or De-comp.
Standard Material in USA for Lead Free Assembly is Isola IS410 180 Tg. / 350 Td.
This material has a different Resin content that is able to with stand the higher Assembly Temps needed to flow lead free paste.
IS410 Material Looks like ceramic material and has similar draw backs, its fragile, Hole quality after drilling is not as good as standard material, Shelf life on its Pre-Pregs is 3 mos versus 6 mos for std FR406 Material and availability is a Pain.
Manufacturing time is also increased due to longer Desmear time after drill to clean the holes out and press time at Lamination to cure the material. Total add between the two is about 3 1/2 hours.
Material pricing from FR406 to IS410 is higher but not by much and this will change as more shops convert to it.
The typical pricing increase from Lead free to Assembly Capable Lead Free Material is around 10%. And this is to cover the increased cost of the material and the increased Manufacturing time.
When to switch to this new material type is an assembly issue, We have deal with some CM's that feel that Standard FR406 material will work just fine with there lead free assembly and they are not worried about De-lam. Others will tell us that FR406 material will de-lam. Allot depends on the CM's Paste selection and profiling.
As a board shop, we explain to our CM's that we will not Warrantee FR406 product that goes through Lead free assembly.
Hope this Helps,
Regards,
Board House
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