Electronics Forum | Mon May 10 11:24:33 EDT 2004 | Charly
Encounter solder ball crack after reflow, found the solder ball is out of shape after reflow, cross section view found that the solder mask opening is not good ( when we do comparason with diff. supplier substrate.) Does the solder mask shape will af
Electronics Forum | Mon May 10 16:37:01 EDT 2004 | davef
First some definitions, the two main types for solder masking near BGA pads are: 1 Pad, Non-Solder Mask Defined. In circuit board design, pads with spacing that does not allow solder (usually bumps) on the pads to contact the adjacent solder mask. [
Electronics Forum | Fri Feb 22 08:26:51 EST 2002 | davef
You are correct. The gold dissolves in the solder. The gold is meant to protect the nickel from oxidizing, so that you can solder to the nickel. Obviously that didn�t work as planned. Your background information is very sparse. Two things come
Electronics Forum | Thu Feb 21 13:08:06 EST 2002 | vincent_f
Hello, I had recently a problem of crack between the solder ball (SnPb) and the Ni layer of the PCB pad. We use Electroless Ni/Au technology for PCB. This phenomena is amazing because the crack is very clean (straight) and it creates a space betwee
Electronics Forum | Tue Jun 22 08:37:52 EDT 2010 | davef
Dennis: These "terminal detach failures" probably are caused by thermal shocking of the components. * Preheat the components * Use a hot air pencil rather than a soldering iron
Electronics Forum | Wed Jun 23 08:47:32 EDT 2010 | mun4o
Hi, about location - components are in the diferent location on PCB.In the one PCB have 7 cap 560pF 0603 , and some of thenm are cracked, another are OK. When I look at 20x microscope , I can't see defect, but ICT measure from 200 to 350pf.When hea
Electronics Forum | Wed Sep 27 17:24:08 EDT 2000 | Wolfgang Busko
Ashok: Plating thickness and ductility of the copper are things to look for. If it�s a crack where two layers are pressed together one possible cause could be bad process parameters while pressing these layers together at the PCB shop with the resul
Electronics Forum | Fri Sep 03 11:45:15 EDT 2004 | rlackey
Hi Ken, I know this doesn't help in the immediate timescale, but isn't avoidance the best form? can you trace the cracking to a process issue (Solder profile, shock damage, handling damage, probe/ATE damage)or a chip cap manufacturing fault? I can'
Electronics Forum | Tue Feb 26 10:55:58 EST 2002 | davef
This could be an electroless nickel / immersion gold specification. While the symmetry of the numbers is pleasing to the eye, but as Joyce Marchand says, "It doesn't blow-up my skirts." Problems with your specification are: * Lower end of the gold
Electronics Forum | Mon Feb 06 17:58:16 EST 2023 | davef
The September 29, 2022 Express Newsletter [ https://smtnet.com/express/index.cfm?fuseaction=archives&issue=20220929 ] has papers on chip cracking
