Electronics Forum | Mon Nov 25 09:06:15 EST 2002 | jax
You might want to check the tin thickness. I believe you have a minimum of .65 microns in order to achieve a good solder joint through 3 thermal passes. In an immersion tin process, the ability to solder is time and temperature dependant. As the int
Electronics Forum | Tue Mar 09 22:26:17 EST 2004 | davef
You should to be soldering to the nickel. The intermetallic is Ni3Sn4. "At relatively low temperatures, the tin-nickel layers form about as rapidly as the tin-copper layers do, but at higher temperatures their growth rate is distinctly lower. At 10
Electronics Forum | Mon Apr 12 22:49:09 EDT 2004 | Ken
I will assume the balls of the device are tin-silver or tin-silver-copper??? There is no reason why you can not run 63-37 solder paste on this device. You will form an intermetallic at the interface structure, however, you will NOT form the 2/3 col
Electronics Forum | Thu Mar 24 07:06:06 EST 2005 | davef
There's a lot of comparison tables on the web. Here's one: Properties - Summary [A Winlow Circatex] Attribute||Hasl||Immersion Silver||Immersion Tin||Electroless Pd||OSP||Eless Ni / Imm Au Shelf Life (months)||12||12||12||12||12||6 Multiple Reflows
Electronics Forum | Tue May 24 19:35:36 EDT 2005 | davef
Certainly, most often, the focus of pot analysis is directed at controlling impurities. Maintaining proper level of tin is important, also. When the portion of tin decreases: * Liquidous temperature increases. * Ability to wet decreases. * Solder c
Electronics Forum | Tue Oct 03 22:48:21 EDT 2006 | C.K. the Flip
It sounds as if this Sn100c HASL process is still in its infancy requiring further process development and characterization..weather its a better more active flux or a different profile... Given your situation of the Sn100c coating actually "repellin
Electronics Forum | Thu Mar 01 22:21:06 EST 2007 | davef
From our notes ... An intense evaluation was completed in 1992 that involved testing of three board types [6 layer FR4, 6 layer ceramic copper thick film, and a 4 layer copper-invar-copper board] by the Navy Surface Warfare Center, Crane, IN. [Obvio
Electronics Forum | Tue Sep 14 14:07:45 EDT 2010 | grahamcooper22
Hi Gani, HASL is normally very good for solderability providing there is a good consistent coating of HASL on the pcb pad. But it is not unusual to have a very thin coating of HASL on the pad and this is poor for solderability. You then have tin/copp
Electronics Forum | Fri Mar 26 15:48:31 EDT 2021 | grahamcooper22
Leaded HASL on small pads can be quite difficult to print on...the HASL tends to be domed rather than flat..and that can affect print quality...you really need a perfectly flat pcb pad to print paste on when you are assembling 0.5mm QFPs. If the pcb
Electronics Forum | Thu Aug 24 16:44:27 EDT 2000 | Dr. Ning-Cheng Lee
There is no IMC composition can be identified in phase diagram of In/Sn. There are some compositions such as In3Sn or InSn4 cited in earlier literature. Those composition should be regarded as approximate representation of solid solution of In/Sn. I
