Hi Steve -Yes ceramic is an excellent conductor of heat so your profiling will be different, delta T is less of a concern for example, but you already deduced that.. So far as panels and individual circuits are concerned you should be able to get your panels scribed (analogous to scoring) so they will snap apart after soldering. Alternatively irregular shaped parts can be profiled leaving only retaining ligaments so they can be popped out. Maybe a combination can be done. If you have a decent laser house they will help you with an optimum design for this, its standard stuff for them. Profiling is expensive so if you can get scribed parts its much cheaper, Contact me off-line if you like on this. Things that people tend to forget - Ceramic is extremely abrasive and can be sharp edged so if you are handling any significant volumes you will get fixtures wear, need a little care when handling - Ceramic does not flex or bounce too well when dropped. - Solder joints may be duller so your inspection criteria needs to be adjusted - Depending on the dielectrics and so forth you may have some problems if you use machine vision, ceramic is pure white when not coated. - Depending on the complexity of the circuitry you may be registering to edges rather than fixture holes or fiducials. Mike Fenner Indium Corporation of Europe T: + 44 1908 580 400 F: + 44 1908 580 411 M: + 44 7810 526 317 -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Stephen R. Gregory Sent: Saturday, August 18, 2001 12:57 AM 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-