David,
IMO, Polyimide is the most stable (Tg = 220 or so) for high temperature
applications.  Risholite came up with a comparable product, but I am not
sure if they were able to sell it or not.  I agree with Dario somewhat.  I
would avoid the Sn93 though.  We've had instances where the BI temperature
in the oven was 150+ and the temperatures under the devices was 20-30
degrees more.  We have an instance when the socket fell off the board
during Burnin.  Verify both and stick to Sn96.  As for the soldermask,
we've experimented with SR1000, SR1020, and SR2020, SR1000 proved to be the
most tolerant (maybe due to the adhesion to tin nickel plating!)
As for vibration issue, someone else needs to tackle that one.  Is this a
burnin board?  What kind of "hole failures" are you experiencing?  Loss of
connection!!


bilal khalaf




>This is similar to a BURN-IN BOARD.
>For burning in devices for up to 150 C we use Polyemide  with Tin Nickel
>plating and SR1020 solder mask. To attach wires use regular Sn63 solder or a
>higher temp solder like Sn96.



>I currently have a customer with an application requiring a 6 layer PCB
>that must exist in a 120 degrees C environment. They are currently using
>silver solder to attach wires to the PCB, and the holes are failing. Did I
>mention there is also a lot of vibration?
>
>Does anyone know of a successful fab stategy, i.e. PCB laminate, plating
>and soldercoat combination that can successfully survive these conditions?
>
>We have been considering using rivets in the holes as a parallel solution.
>
>All comments are welcome.
>
>djr