Electronics Forum | Thu Jun 30 20:17:19 EDT 2005 | davef
Matt: What thickness of hard gold was applied to your customer's boards?
Electronics Forum | Thu Jun 30 21:55:33 EDT 2005 | Mason Hughes
Hi, In response to reading height or gold thickness, I can do that masonhughes@sbcglobal.net
Electronics Forum | Tue Jun 28 19:58:59 EDT 2005 | davef
Michael: What's this "tint"? How do you do it? Tell us more, please.
Electronics Forum | Wed Jun 29 16:25:51 EDT 2005 | mattkehoe
When discussing this with the customer he said that his vendor recommended a hard gold plating finish on the board due to the BGA. I said "hard gold"??? And he said yes, hard gold. Turns out the boards were plated with hard gold, not ENIG. Thank
Electronics Forum | Tue Jun 28 19:56:59 EDT 2005 | davef
Matt: Yes, if the gold was really thick, it could appear like your pictures. In measuring gold plating thickness, we'd want to use xray fluorescence [XRF]. For alternatives, look here: http://www.pfonline.com/articles/pfd0027.html
Electronics Forum | Wed Jun 29 17:18:41 EDT 2005 | GS*
Very interesting tread, many thanks to all. Matt please, now what does it mean for you? Will your custmer accept dull solder joints or will the plating be changed ? (ie. HASL, ENIG, etc) Tnks and regards GS*
Electronics Forum | Tue Jun 28 09:13:46 EDT 2005 | russ
It appears that the reflow profile was incorrect or the paste was in bad shape on these boards from what I can see. I personally have never seen a board finish cause this symptom.
Electronics Forum | Tue Jun 28 10:41:57 EDT 2005 | GS
I am not an expert but just for my understanding: - solder paste used ? NC ? other ? - reflow in Air or N2 ? - temp ramp up before soack (�C/second) ? Tnks GS
Electronics Forum | Tue Jun 28 13:23:56 EDT 2005 | Bob Gilbert
Matt, Try a cooler profile by simply speeding up the conveyor by 10%. The difference may be the temperature the pads are reaching between the HASL boards and the Au boards. Are they the same thickness?
Electronics Forum | Tue Jun 28 17:38:13 EDT 2005 | mdang
We got the same problem. To solve it, we have to tint the pads first and do the normal reflow process. It works but take a lot of time to tint the pads. Any thoughts? Thanks, -Michael
