Electronics Forum | Tue Apr 13 09:46:39 EDT 2004 | davef
Now, that's different. We misunderstood the problem from your original descrtiption. We thought the voids were showing at the via in the pad. Now, we understand the voids appear to be in the solder balls. Suggestions are: * Search the SMTnet Arch
Electronics Forum | Tue Apr 13 15:44:41 EDT 2004 | Dreamsniper
Hi Guys, Thanks for all your informative replies. I do know that Motorola is using a No Clean Eutectic Solder for their BGA's. We are in Aerospace and is using a Water Soluble Paste Flux. Now, a) Can anyone explain to me about the effect of thei
Electronics Forum | Fri Apr 16 11:03:35 EDT 2004 | davef
Your copper corrosion is not good. It indicates that you have not done a good job in cleaning. [We assume this is a medium green color, not unlike the color of the solder mask on your board, that is almost like a translucent lacquer; rather than th
Electronics Forum | Wed Apr 21 11:33:20 EDT 2004 | tigerlordgm
As one of our small batch processes, we place BGAs on PCB without using solder paste. We apply tacky flux to a predetermined height on a pallet, "dip" the BGA into the tacky flux to wet the solder balls to the set height, and then use a BGA rework st
Electronics Forum | Wed Apr 21 18:24:13 EDT 2004 | pjohnson@volterra.com
Simple process - we use similar Kester solder brands of "no clean" low residue solder wick to clean our pads, then brush with isopropyl, and apply Kesters brand of tacky flux under a Leica 6x microscope. We do this on 7x7mm and 9x9mm packages. This w
Electronics Forum | Wed Apr 21 17:08:32 EDT 2004 | dave
Congratulations on your new customer. This could be a keeper. Here's what you're familiar with: Electroless Nickel - per MIL-C-26074 and ASTM-B733. Electroless nickel describes the plating of nickel deposits, which may contain phosphorus and boro
Electronics Forum | Fri Jul 23 14:41:41 EDT 2004 | Steve Stach
Dear JSK, It sounds like the root causes of your problem are two fold. First, excessive heat will polymerize the abietic acid found in rosin forming neo-abietic diamers and polymers which are much less soluble than the parent monomer. There are
Electronics Forum | Tue Aug 31 13:23:37 EDT 2004 | frankracine
Thanks Ken for your reply. Concerning OSP, there are a few negative points that I must considered for our application. I've read all the following points in an Entek document. Never test it. - If you have a miss print and you clean the PCB, the co
Electronics Forum | Fri Sep 24 11:08:13 EDT 2004 | davef
We're not sure what you mean by temperature sensitive components. From an assembly process stand-point, every component we use is temperature sensitive to one level or another. More specifically, some of our products use polyphenylene sulfide (PPS)
Electronics Forum | Tue Nov 09 13:36:03 EST 2004 | russ
If I remember correctly since I cannot find my copy of IPC 600, I believe that the 20% reduction applies to "defects" and not the total etch process. By the way what is being used to measure down to .0005"? For this measurement to be correct it wou