Electronics Forum | Wed Jan 09 17:03:44 EST 2002 | rob_thomas
We follow IPC-2221 recommendations for Au and don't have a problem as long as the Ni is under 150 microinches.This ensures a consistent process for us.Also we do plasma clean after SMt and prior to wirebond.That makes a big difference. Rob
Electronics Forum | Thu Nov 03 02:34:46 EST 2005 | Rosewood
We've recently encountered some problems with wire bond strengths. I'm looking for anybody that has had some experience with different types of substrate contamination and methods for cleaning. There is no visible contamination on the gold pads, bu
Electronics Forum | Thu Nov 03 12:48:14 EST 2005 | Rosewood
We have some no sticks, but that is actually a good thing because we have NSD. During process control audits we found that pull strengths to the board dropped off. We build a military application that requires higher bond strenghts. Low pull streg
Electronics Forum | Wed Jan 09 21:19:49 EST 2002 | davef
When I said "In this area, there is no difference between your experience in ceramic substrates and PTFE substrates." I was referring to the area we were discussing ... gold plating. I am sorry if you thought I ment than the wire bonding process wa
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 Mar 05 04:39:38 EST 1999 | Pan Tian Shun
I need advise on how can bonding of ICs to flex foil be done. The pitch of bonding is between 70 to 100 microns and the foil thickness is from 25 to 35 microns. Anyone, please enlighted what kind of bonding technology (thermo-sonic maybe), and curre
Electronics Forum | Sat Mar 06 08:45:16 EST 1999 | Dave F
| I need advise on how can bonding of ICs to flex foil be done. | The pitch of bonding is between 70 to 100 microns and the foil thickness is from 25 to 35 microns. | | Anyone, please enlighted what kind of bonding technology (thermo-sonic maybe), a
Electronics Forum | Thu Nov 03 21:40:40 EST 2005 | davef
There maybe multiple drivers to your problems. * First, decreasing bond quality with time indicates a plating issue. What's the actual thickness of your gold and nickel on the pads? * Second, the no-sticks indicate contamination. If it's organic, p
Electronics Forum | Wed Jan 09 17:14:48 EST 2002 | mregalia
Do you bond with Al or gold wire? What happens if the Ni is over 150 microinches? Thickness of nickel is one those things that we have not been consistent with. The industry seems to pretty much universally call for 100-200 microinches. Our old board
Electronics Forum | Wed Jan 09 12:20:00 EST 2002 | mregalia
Thanks for cluing me into IPC-2221. Though the numbers they give seem to contradict what I have learned from people working with the materials. At least I now know where the guideline for a max of 30 microinches of gold for soldering comes from. But
