Electronics Forum | Wed Jun 18 16:03:03 EDT 2003 | mkehoe
Orrrrr, just buy a small reflow oven, 5K to 7K, and eliminate the paste printing by using solid solder deposition. No shorts, no opens, no cleaning, and no voids. www.sipad.com If you decide to print your own paste later you can invest the extra 30
Electronics Forum | Thu Jun 19 20:47:57 EDT 2003 | davef
Your solders could have vasty different liquidous points. Check with your suppliers to determine the appropriateness of the materials you have selected. Awhile ago Jim Zanolli at Teka hosted an OnBoard Forum here at SMTnet. He'd be happy to give y
Electronics Forum | Fri Jun 20 09:38:56 EDT 2003 | caldon
Hi John- First, I do not have first hand experience so my input is pure theory. This type of package (in Some Cases) has a center grounding bonds and leadless legs ups the difficulty tremendously. With no stand-off from the Balls(or Legs) when the so
Electronics Forum | Tue Jul 08 18:53:21 EDT 2003 | MA/NY DDave
Hi The answer in general is no mixing of Lead Free with Sn/Pb solder. If you look at reliability data, failures after stress tests and then SEMs, failures occur at grain boundaries inside the joint. Lots more happens. By the way this mixing happe
Electronics Forum | Wed Jun 25 06:43:06 EDT 2003 | cyber_wolf
We are currently producing a board for a customer that has about 400 gold fingers that get wire bonded after the assy. leaves our facility. We have tried many different approaches to ensure that we are not getting solder on the gold fingers. Nothing
Electronics Forum | Sat Jul 05 07:30:04 EDT 2003 | AlCapone
If the problem as you described as the gold plating contaminated, and the Nickel layer exposed to the solder pot. However, the purpose of the gold layer is to protect the nickel and copper layer not turn into corrosion and resist to other issue (humi
Electronics Forum | Thu Jul 17 04:42:47 EDT 2003 | sanjeevc
Hi! One technique: 1. Remove all balls 2.Make > a mask(stensil)for reballing.The holes of the > mask must be 0.8-0.9 the size of the pads. 3. > Reball chips 4. Reflow chips Good luck Hi Yes,we have done quite a bit of reballing of BGAs with
Electronics Forum | Wed Jul 09 18:02:48 EDT 2003 | slthomas
Just when you think you're getting somewhere... QA sent me a vendor response to our corrective action request. They stated that their normal process for this product includes an ultrasonic cleaning cycle of 20 MINUTES minimum. It might be 30, we'r
Electronics Forum | Mon Jul 14 16:26:58 EDT 2003 | slthomas
Yes, they do the cleaning, we did the (apparently first) inspection and caught the problems. They tried a shorter cleaning cycle, witnessed no defects, and attributed the defects on the boards we had to their cleaning process. Now they just plan on
Electronics Forum | Tue Jul 15 11:18:29 EDT 2003 | slthomas
It is an interesting situation....one that merits as much business philosophy analysis as technical analysis. I'll be getting my official 60 day notice today. Any criticism about our overseas suppliers (that were selected by sr. management w/o in
