Steve,

You can get ceramic scribed (I think we had a CO2 laser in a past life) in
very finely spaced holes (every 0.005" I think it was) that would make
singulation very easily done, using nothing but 4 fingers. I would recommend
using 62/36/2 alloy paste to help avoid any leaching and make sure the
components that have been spec'd are compatible with ceramics reflow, i.e.
coefficient of expansion.

Hope this helps,

Mike Di Giacomo, P.Eng.
Process Development Engineer
WorldHeart Corp.


-----Original Message-----
From: Stephen R. Gregory [mailto:[log in to unmask]]
Sent: Friday, August 17, 2001 7:57 PM
To: [log in to unmask]
Subject: [TN] Assemblies using ceramic substrates...



Hey all,

This message is going out Friday night, so I know I won't hear much until
next week. But anyways, we may be getting some work for an assembly that is
on a 2" X  2" ceramic substrate...double sided SMT by the way...

I know that things are going to be different than the standard fiberglass
substrate assemblies, IE: more heat for reflow, ect....but is there anything

else that I should watch out for?

Did some ceramic substrate stuff a while back at a past employer, but it was

single side stuff and didn't really present too much of a problem..

I was asked if we could put them in a panel, and as far as I know, you don't

want to do that unless you have some very specialized singulation equipment
to singulate each assembly. I thought I would get some workpiece fixturing
and leave them in their 2" X  2"  size...

Sorry if I'm asking dumb questions, but as once said; "The only dumb
question
is the one that's not asked..."

Thanks, and I hope ya'll had a good weekend...

-Steve Gregory-