Electronics Forum | Tue Dec 01 07:24:44 EST 1998 | Earl Moon
| Hi folks , | Lately we are seeing a lot of rawcards with black spots on the pads - most of them have Au finish(immersion gold) . We did a lot of inspecton after wave solder and found that only (fine pitch) QFP are affected the most. Our inspection
Electronics Forum | Tue Dec 01 07:54:49 EST 1998 | kallol chakraborty
| | Hi folks , | | Lately we are seeing a lot of rawcards with black spots on the pads - most of them have Au finish(immersion gold) . We did a lot of inspecton after wave solder and found that only (fine pitch) QFP are affected the most. Our inspec
Electronics Forum | Wed Oct 10 20:58:30 EDT 2001 | davef
Several points are: * There�s quite a bit of background on IMC in the fine SMTnet Archives. I�ll try not to duplicate it. * If you have a smooth and well-formed solder connection using fairly common materials, you assuredly will have IMC. Any evide
Electronics Forum | Thu May 21 09:54:07 EDT 1998 | Justin Medernach
| I'm reviewing my board fab spec. It calls for a minimum SnPb thickness of 50 microinches on HASL PWB's. I've looked at other specs that call out anything from 30 to 80 microinches, and others that just say the copper pad must be covered and solde
Electronics Forum | Tue May 26 14:50:07 EDT 1998 | Dave F
| | I'm reviewing my board fab spec. It calls for a minimum SnPb thickness of 50 microinches on HASL PWB's. I've looked at other specs that call out anything from 30 to 80 microinches, and others that just say the copper pad must be covered and sol
Electronics Forum | Fri Jul 18 10:46:43 EDT 2003 | davef
If you are saying that you have discolored white tin at in-bound inspection, you have bad boards. The boards are fabricated incorrectly. Your fabricator is deficient. That is the GREAT thing about imm coatings. You can look at them and determine
Electronics Forum | Mon Jan 31 12:24:24 EST 2000 | Dave F
Robert: Several points: 1 Dross is a mixture of various things with no "fixed" composition: � The obvious things are metal oxides mixed with metal and this can vary in color with temperature and composition - remember some intermetallic oxides form
Electronics Forum | Tue Dec 01 09:02:18 EST 1998 | Earl Moon
| | | Hi folks , | | | Lately we are seeing a lot of rawcards with black spots on the pads - most of them have Au finish(immersion gold) . We did a lot of inspecton after wave solder and found that only (fine pitch) QFP are affected the most. Our in
Electronics Forum | Fri Dec 04 20:26:34 EST 1998 | kallol Chakraborty
| | | | Hi folks , | | | | Lately we are seeing a lot of rawcards with black spots on the pads - most of them have Au finish(immersion gold) . We did a lot of inspecton after wave solder and found that only (fine pitch) QFP are affected the most. Ou
Electronics Forum | Fri Dec 04 20:37:45 EST 1998 | kallol chakraborty
| | | | | Hi folks , | | | | | Lately we are seeing a lot of rawcards with black spots on the pads - most of them have Au finish(immersion gold) . We did a lot of inspecton after wave solder and found that only (fine pitch) QFP are affected the most