Electronics Forum | Wed Jan 09 14:52:53 EST 2002 | Chris
Hi, I have read many articles about theromsonically bonding to soft gold. Many of these articles state you can bond to 10uinches of gold. I have worked with both Hughes and Panasonic bonders at two different companies and I have never been able to
Electronics Forum | Mon Jan 07 20:37:15 EST 2002 | davef
For soldered areas, we like to keep gold thickness substantially below the maximum you propose. Search the fine SMTnet Archives for our discussions on the topic of acceptable levels of gold with solder connections. Let�s fix this �no one seems be s
Electronics Forum | Fri Sep 12 13:14:33 EDT 2003 | Mark Kostinovsky
A little adition to Norm's statement: Sn-Pb intermettalic compounds do not accept solder as they are (even without being oxidized).
Electronics Forum | Wed Sep 10 12:56:09 EDT 2003 | davef
Intermetallic compounds [IMC]: * Form during the alloying process of some metals. In soldering these are Sn, Ni, Ag, Cu, Au. * Do not accept solder. * Increase in depth in logarithmic proportion to both time and temperature. [So during the solder
Electronics Forum | Mon Sep 23 18:11:10 EDT 2002 | steveb
On an assembly reflowed in air saw the same thing: 0201's with a grainular solder joint, but 0402's and above with perfectly formed joints. Reflow profile all within acceptable tolerances. Reflowing in nitrogen solves this problem, but increases t
Electronics Forum | Wed May 20 17:18:09 EDT 2009 | daxman
Just out of curiosity, how are you or anyone else determining a defect? Last I checked, IPC had no criteria yet for solder defects for QFN components. Has this changed? Biggest problems we see are voids which our x-ray shows a lot of. Our problems
Electronics Forum | Thu Feb 22 04:00:02 EST 2001 | Scott B
We are increasingly being asked to store components for longer and longer periods which we know through experience leads to reduction or total loss of solderability of the parts. 1) What is the industry accepted shelf life of tin/lead plated compone
Electronics Forum | Tue Nov 11 17:35:08 EST 2008 | davef
SM-840, is a material qualification document only, with all the test requirements applicable only to a defined test coupon, not to production boards. So, it's useless for what you're trying to accomplish. As assemblers use A-610 - Acceptability Of E
Electronics Forum | Mon Sep 17 16:03:13 EDT 2001 | jschake
The results from an experiment comparing 27 different combinations of pad dimensions concluded that the pad design with 15 mil pad length, 12 mil pad width, and 9 mil pad separation produced the best assembly yields. A 5 mil thick laser cut stencil
Electronics Forum | Mon Jul 12 11:35:27 EDT 2004 | Pierre RICHARD
Here are some answers to my questions after a good research. I also added more definitions that could help understand this esoteric language used in assembly, specially surrounding fluxes and their use. In blue italics are comments and extracts from
