Electronics Forum | Tue Mar 24 22:03:39 EDT 2015 | davef
Here's some notes from IPC APEX 2015: * Black underfill is Heraeus. It needs to be preheated to 180-200*C for rework. Above 200*C it changes state and becomes difficult. * Clear underfill is from an unknown Korean supplier. * People from Heraeus w
Electronics Forum | Wed Dec 06 21:59:37 EST 2006 | SMTrework
Hello, we rework BGA packages that come back from the field. I've seen on occasion a black and or red "epoxy" substance from the manufacturer on the corner of some board's BGA chips that I imagine are applied to increase corner bond of the chip to th
Electronics Forum | Wed Dec 06 22:46:39 EST 2006 | SMTrework
Hi Dave, This is manufacturer applied epoxy / adhesive to minimize package "lifing" from chassis flexing and thius board flexing. I have seen the complete array area covered with this black or red epoxy in some cases (i.e. the underfill that I've
Electronics Forum | Mon Dec 21 14:38:11 EST 2009 | bandjwet
Does anyone know of a vendor of "black top" to fill in voids left by laser "X-out" patterns in the top of an epoxy (plastic) package ? We are demarking an area of a device and would like to fill it in with something other than a colored epoxy. Reg
Electronics Forum | Thu Feb 15 12:34:11 EST 2007 | flipit
Does Ekra or MPM require stencil fiducials be filled with Black Max or some other black epoxy? We still require our stencil supplier to do this. I did not have to do this on any Dek solder printers since 1997. Can the MPM UP2000 HiE fiducial light
Electronics Forum | Tue Nov 05 09:21:18 EST 2002 | stefwitt
After all, you may want to consider a Flip Chip process. The chips are bumped with tiny solder balls while still on the wafer. You may present the bumped chips in Gel Pack, trays or Surftape to your Pick $ Place machine ( if capable for Flip Chip pl
Electronics Forum | Thu Feb 15 13:18:16 EST 2007 | slthomas
The E5s I had just needed the fids to be burned black. Never needed epoxy, although we did have one stencil that we had to touch up with a sharpie now and then because they didn't burn it dark enough (too hot...?).
Electronics Forum | Mon Jul 13 07:25:09 EDT 2009 | hcarrasco
Hi everybody, > We recently start to use an ultrasonic stencil cleaners for our stencils. > It' work well, but after some time, we saw a lot of fiducial that the black > epoxy have been partially or totaly remove. I want to know if someone h
Electronics Forum | Tue Nov 05 06:51:59 EST 2002 | V.RAMANAND KINI
Hi, This is a widely discussed subject and since you have asked a brief explanation, I assume, you are a business man or a top executive in the company venturing in to COB. I waited to see if someone replies to you. May be it is a very old subject
Electronics Forum | Wed Jun 09 15:03:53 EDT 1999 | Earl Moon
| In past PCB designs I have cleared all traces from all layers | (except pwr/gnd) from fiducial area. It has come to my attention that this is only necessary on the side where fud is placed. Which is the correct method of design using a fidicial?
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