Posted by Happy: Mon Mar 19, 2007 9:01 pm    Post subject: Lifted Ball at Pad

Hi! Is there anybody who can advise me what are the causes of the lifted ball at Pad. We have received some units from our customer and FA result after SEM shows that there is not enough adhesion of the AU ball and the metallization. EDX shows no anomaly. Machine parameters used during the lot processing are okay. Thanks for any advise who can give me.

Posted by FARel Engr: Wed Mar 21, 2007 1:37 am    Post subject:

Hi Happy, you may want to start with this link:

http://www.EESemi.com/bondlifting.htm

Posted by Spider-boy 300: Tue May 22, 2007 12:07 pm    Post subject:

There are many causes of Lifted Bond on Pad.

When its material related this type of occurence may be attributed to the quality of the bond pad's surface. Some pads may be inherently contaminated during fabrication, and some may have accumulated Si dust during wafer saw, and was not completely cleaned during its washing process, but since EDX shows no problem material issue is definitely out of the question.

LBOP can also be caused improper set-up. Machine factors such as improper USG calibration,wrong Heater block temperature,wrong bonding tool used are some of the factors which can cause LBOP. Correct parameter setting must also be ensured during set-up. You can also try to check the process history, machine log and system log for any errors and downtime encountered during the time of the processing.

I know that my reply was quite off timing for I just registered recently, but I hope these may help you in the future.

Posted by Paulpang: Thu Jun 07, 2007 9:34 pm    Post subject: Re: Lifted Ball at Pad

Is there any TODD before destructive analysis ?

Posted by wbshall: Sat Aug 25, 2007 11:07 am    Post subject: added querry regarding NSOP from Happy

Would like to add querry besides "Happy" concern Regarding NSOP.

I've sent some samples for EDX and found element of Fluorine, would this element cause a lifted ball on pad. Also would to like to ask if there are some presence of contaminants on pad, would it be able to quantify the amount of contaminants to say cannot bond or can bond. Plasma cleaning though wouldn't help much as per observation.

Thanks!
WbShall