Electronics Forum | Thu Mar 02 15:12:50 EST 2000 | Robert Hartmann
To restate my question of earlier, if I have a .020" sphere before reflow, and my pad opening in the dielectric is .017", is there a rule of thumb to calculate the height of the sphere after reflow? We are using 62Sn/36Pb/2Ag spheres. This should h
Electronics Forum | Fri Feb 25 16:04:18 EST 2000 | Dave F
Sze-Pei: Are talking BGAs here? Flux type? Profile? Pad material? Aperture size? We won�t want to give people too many hints on what the problem is would we? BGA voiding is a function of materials, methods, environment, and human factors. Con
Electronics Forum | Mon Dec 11 15:12:20 EST 2000 | accuspec
we are using alphametals no clean 95sn/5ag CL775 paste. After reflow there are solder balls on the board. mainly are around the cap. We are using a conceptronic concept 60 air. There are 4 zones with 8 chambers. We are not sure what the profile
Electronics Forum | Thu Mar 02 15:12:50 EST 2000 | Robert Hartmann
To restate my question of earlier, if I have a .020" sphere before reflow, and my pad opening in the dielectric is .017", is there a rule of thumb to calculate the height of the sphere after reflow? We are using 62Sn/36Pb/2Ag spheres. This should h
Electronics Forum | Fri Feb 25 16:04:18 EST 2000 | Dave F
Sze-Pei: Are talking BGAs here? Flux type? Profile? Pad material? Aperture size? We won�t want to give people too many hints on what the problem is would we? BGA voiding is a function of materials, methods, environment, and human factors. Con
Electronics Forum | Thu Feb 15 07:25:05 EST 2001 | Nick
0.5um(Ni~6.5um) after reflow(data taken in 48hrs).But after performing temperature cycle test ,the former aging rate(from the shear strength ) seems faster than the latter.Why!?Someone call this the 'precipitation hardness',but what actually is it! A
Electronics Forum | Thu Jan 27 14:16:14 EST 2000 | Tuan Bui
I've tried Indium NC-SMQ92(96.5Sn 3.5Ag) on these MCMs and achieved only marginal wetting on pads and parts. The good wetting is what I try to achieve, shiny is what my engineers want (Prototype environment). Does pre-cleaning the PWBs in ultrasonic
Electronics Forum | Mon Jan 11 09:00:17 EST 1999 | Kelvin Chow
Some of my friends ask me if sombody use lead free solder ball on BGA, espically PBGA packages. I wonder if 96.5Sn/3.5Ag (m.p .221 oC) or 58Bi/42Sn (m.p. 138 oC) would be suitable candidates? Do you have any experience on this subject? Kelvin
Electronics Forum | Tue Aug 14 21:42:13 EDT 2001 | davef
2% silver will be a little shinier. [Some inspectors hate that.] After that differences get murkier. Some people believe that 2% silver does something er other to scavange gold and silver to produce a less brittle connection. We have never seen ev
Electronics Forum | Fri Feb 22 15:16:24 EST 2002 | rkevin
Bet your using tin/ lead plated components with a lead free Cu/Ag/Sn alloy. It leads to intermetallic cracking. Wow didn't anyone tell you to check the archives yet, It seems to be the answer given to everyone. Why have an interactive site if you alw
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