Electronics Forum | Thu Jul 19 18:25:42 EDT 2012 | boriskilk
We have picked up a new customer who is insisting on Ionic cleanliness less than 6.45u grams/cm2 when measured in accordance with OPC-TM-650 Method 3.26.1 with measurements made immediately prior to solder mask application. This is the first request
Electronics Forum | Tue Oct 09 22:42:38 EDT 2012 | davef
You're correct. It hinges on who's talking about a "production printed board." * You think a "production printed board" is the board that you're trying to produce and ship. * Your fab thinks a "production printed board" is a 30-up panel. It would be
Electronics Forum | Wed Feb 13 14:01:37 EST 2013 | davef
Things that come mind are: * Not sure why you want to do this, since probing solder gives a longer probe life than probing copper. * I've never tried it, but I see no reason why you couldn't probe Kapt0n or blue painters tape. * Fabs [or you] can pri
Electronics Forum | Tue Feb 19 18:51:45 EST 2013 | tombstonesmt
We've had great success with acrylic based cut with xylene. Very accurate with little to no masking necessary for keepout areas, very rarely have to make adjustments on our Asymtek. On the other hand we have an Asymtek dedicated for silicone coatin
Electronics Forum | Fri Mar 15 18:44:34 EDT 2013 | anvil1021
We will try both the solder mask and the .001" Kapton and see where we end up with each. This is a fine pitch dual row QFN and we cannot afford too much paste on the .004" stencil we are using. We have experienced shorting in the past with .005" sten
Electronics Forum | Mon Jul 08 14:52:40 EDT 2013 | hegemon
The smaller ball "missing" from the lower left is from solder migrating down into the adjacent via. The solder mask may have been damaged or missing prior to mounting the BGA device. The larger balls at the top right are due to uneven heating during
Electronics Forum | Tue Aug 13 11:20:41 EDT 2013 | horchak
Is this a new issue? You could run a wide piece of masking or duct tape along the oven seal on the outside just to see what happens. What is the heating plate configuration. Are they solid from front to back or split. My thought here is if there is a
Electronics Forum | Wed Jan 22 10:24:23 EST 2014 | cyber_wolf
No matter how good your process is, you will get solder on the gold fingers/lands unless they are protected. We have proven that solder will get on the gold fingers in the reflow oven. How that happens....we arent't 100% sure...there are a lot of the
Electronics Forum | Wed Jul 15 18:04:43 EDT 2015 | mikekeens
If it is important to have vias within thermal pads to help dissipate heat i would recommend using solder mask to stop the solder from wicking down the holes and resulting in insufficient solder. Some further info can be found here:- http://www.surf
Electronics Forum | Wed Mar 11 18:28:03 EDT 2015 | gregoryyork
Hi its undercured solder resist which leaves a clear waxy/oily residue and can be seen as brown tar/oil in the molten solder wave. This also causes MicroSolder Balling and some snail trails of solder pick up and worst case bridging and peeling resist
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