Electronics Forum | Fri Sep 28 07:42:07 EDT 2007 | zanolli
We have the need to verify that proper intermetallic layer between a 100% Sn plated contact and the solder joint is being formed. Never having done this before: Is there any specifications, etc. that we can use as acceptability criteria?
Electronics Forum | Fri Sep 28 16:49:48 EDT 2007 | davef
good * No IMC => bad Intermetallic growths are diffusion limited, and therefore the thickness of the intermetallic is given by: z^2 = (Do)(t)exp[-Q/RT] Where Do (m^2 s-1) is the diffusion coefficient, T(�K) is the temperature, Q (J mol-1) is the act
Electronics Forum | Mon Jul 06 20:32:34 EDT 1998 | Chiakl
Hi there, I am looking for some informations concerning the shear or pull strength of a typical TQFP 20 mils leads in relationship with the Copper/Tin intermetalic layer thickness. Could anyone help? Thank in advandce. rgs, chiakl
Electronics Forum | Thu Jul 09 21:04:50 EDT 1998 | Dave F
| Hi there, | I am looking for some informations concerning the shear or pull strength of a typical TQFP 20 mils leads in relationship with the Copper/Tin intermetalic layer thickness. Could anyone help? | | Thank in advandce. | rgs, | chiakl Chiakl
Electronics Forum | Mon Feb 12 13:58:10 EST 2007 | campos
Tks for the answers,, My concern is about the intermetalic layer,,I run SMQ230 LEAD FREE paste.. its liquidous at 217C..the oven have 7 zone, but I run in 5 zones also with a more agressive profile (due to the line rate)..I would like to know if runn
Electronics Forum | Fri Dec 03 18:01:39 EST 1999 | Dave F
Chris, Two points of perspective are: 1 Solderability: The shelf life of components has elapsed when they are no longer solderable. There's tons of variables that affect this, but keys are: * Intermetalics grow as a function of temperature. * Th
Electronics Forum | Thu Sep 17 04:48:51 EDT 2009 | grahamcooper22
The colour you see on the pads is tin/copper intermetallic layer. In your reflow the immersion tin coating and the copper pad underneath react to form in intermetalic layer. The effect is worse the hotter the pcb or area of the pcb gets. In IR reflow
Electronics Forum | Fri Oct 10 13:35:56 EDT 2003 | swagner
Does anyone have any data about the dangers of reflowing BGA's twice? I have a customer that is concearned about cracking in the intermetallic layer after the second pass. Thanks in advance.
Electronics Forum | Thu Jan 15 09:04:36 EST 2004 | rkevin
Does anyone have any information about eliminating voids on BGA using SN62 as opposed to the normal Sn63, something which explains the inter-metallic layers which form during the soldering process and the leaching out of silver ?
Electronics Forum | Tue Aug 03 17:13:41 EDT 2010 | bradlanger
Craig, If it is LF Hasl it sounds like it applied too thin exposing the intermetallic layer wich is not solderable. We call out a minimum thickness of 80 microinches and have good results. We have had shops in the past that did not control the Hasl
