Electronics Forum | Mon Jan 03 16:34:10 EST 2005 | davef
The main advantage if ENIG over HASL is that ENIG is flat and HASL generally is not. The main disadvanages to ENIG over HASL are: * Cost of ENIG is 1.5 - 2X higher than HASL * Selflife is less than HASL * You solder to nickel, rather than copper * E
Electronics Forum | Tue Oct 07 08:38:05 EDT 2003 | davef
J-STD-001C requires removal of gold from (through-hole) component leads when the thickness of the gold layer is above 2.5 microns to prevent problems with embrittlement. The thickness of gold on an ENIG board typically is around 0.05 micron, resultin
Electronics Forum | Tue Aug 17 13:24:47 EDT 2004 | blnorman
We have parts that have electroplated tin over nickel. The mfg. assures us the minimum thickness of the tin is 5 microns. Cross sections have shown many instances of 1 micron and pits that go down to the nickel barrier layer. A request for thicker
Electronics Forum | Thu Jul 10 09:16:41 EDT 2008 | aj
Hi all, What should the typical gold thickness be on ENIG boards ? aj...
Electronics Forum | Mon Oct 06 12:37:18 EDT 2003 | ramanandkini
It was a nice discussion. What I did here was a thermal shock test 1 hour@ +90 deg.c and immediately 1 hour @ -40 deg.c. The second test I did was a high humudity test for a week. After each test, I carried out a peel test with scotch tape. Those bo
Electronics Forum | Wed Oct 01 21:22:37 EDT 2003 | ramanandkini
We have a 1.6 mm thick automotive PCB board of size 35x70mm. One of our vendor has given us a batch with lesser soldermask thickness 5~8 microns. Will this affect the circuit board on a long term. What should be standard for the soldermask thickness?
Electronics Forum | Tue Jul 15 16:30:57 EDT 2008 | boardhouse
Hi Aj, Recommended Immersion gold thickness would be 3-5 Micro inches over 140 -200 micro inches of Nickel. Thicker Immersion gold than 5 micro inches can cause solder joint embrittlement. Gold readily dissolves in molten solder and will be present
Electronics Forum | Wed Aug 09 08:06:07 EDT 2006 | davef
See "IPC-4554 Specification for Immersion Tin Plating for Printed Circuit Boards" 3.2.1 Immersion Tin Thickness. The most common reason for solderability issues with the white tin surface coating during multiple thermal excursions is a thin white ti
Electronics Forum | Wed Sep 17 10:49:48 EDT 2003 | davef
We agree. Colin Lea showed that HASL less than 2 microns [80 uin] thick has limited shelf life and that shelf life gets worse as the HASL gets thinner. Unless you do not need shelf life, consider sticking with 100 to 500 uin. There is nothing wrong
Electronics Forum | Tue Oct 07 02:18:13 EDT 2003 | iman
Hi Experts, Pls help advise what is the expected range of PCB gold thickness over Ni (for ENIG/Electrolytic fabrication processes)? any referrence standards set by the IPC?