Electronics Forum | Tue Feb 18 16:31:43 EST 2003 | arturoflores
Haran: Have you made improvements regarding your BGA shorts? We are facing the same problem and we think it is partly because the non coplanarity of the seating plane of the BGA which causes BGA balls to squeeze on one side of the BGA. Also, we ha
Electronics Forum | Fri Oct 05 09:41:40 EDT 2001 | davef
Is this http://www.smtnet.com/media/images/bgabridg2.jpg what yer seeing?
Electronics Forum | Fri Dec 27 01:26:08 EST 2002 | haran
Currently we are running a BGA with a big thermal pad in the middle of the package and encountered high defect of solder shorts.I would like to check whether anyone has experience this problem and how this can be rectified?.
Electronics Forum | Thu Oct 04 13:04:52 EDT 2001 | Hussman
Without seeing your X-ray, it sounds like your BGAs are out gassing. This casues the situation you described. Try baking some BGAs and run them along with ones not baked to see.
Electronics Forum | Tue Feb 18 18:20:19 EST 2003 | davef
Arturo, For a continuation of Haran's thread, look here: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=22856
Electronics Forum | Wed Oct 03 12:02:04 EDT 2001 | kjwaskow
We are getting solder blobs forming in open areas of the BGA, between the center array and outer array. THe ceter array balls are starved of solder, so they are presumably the source. The theory we hold is possible moisture causing the solder to mo
Electronics Forum | Wed Oct 03 17:06:43 EDT 2001 | davef
Yes, moisture entrapment causes solder shorts 80% of the time. Cracks occur bottom side of the BGA. Use an acoustic microscope to find the cracks. So, what makes you think your BGA are blowing-off steam? I posted a vid on SMTnet that showed the b
Electronics Forum | Thu May 15 07:37:49 EDT 2003 | pteerink
Have seen similar circumstances a couple times. Possible causes: 1) PCB defect - remove the BGA and inspect/test the PCB for shorts. ( trace short, layer short etc ) 2) PCB defect that only shows up when the BGA is populated - a short somewhere o
Electronics Forum | Thu Feb 04 01:34:51 EST 1999 | Joe Cameron
Hello all, Are BGA's easy to develope shorts? If a process is stable and all of a sudden you get BGA's shorting out on you, what might be problems? We've checked our solder paste amount, and we've rechecked our reflow profiles and nothing has chan
Electronics Forum | Wed Nov 23 07:39:14 EST 2005 | chunks
Shorted to the sheild or the BGA balls are shorted? Sheilds move a lot during reflow. If this is the case, place some adhesive or peelable solder mask on either side of the shield and baords to stop it from moving.
