Just a thought from another point of view- tell me if I am wrog- Seeing voids in the solder joint you know nothing about when inspecting a BGA by X-Ray could be something positive if they are not in excess- at least you know that melting took place. If you have a laminograph and you can locate them- at the interface or inside the ball- good for you. I don't have a laminograph and perfect balls without any voids make me suspicious.
Gaby
----------
From: Guenter Grossmann[SMTP:[log in to unmask]]
Reply To: TechNet E-Mail Forum.;Guenter Grossmann
Sent: יום שלישי 17 אוקטובר 2000 10:14
Subject: [TN] Antw: [TN] voids in BGA
Tom
Well without a picture of what you called small voids it is difficult to say something about your solder joints. However, I heard people saying that there is no such thing like an SMT solder joint without voids. From the material behaviour and what I know I dare to say that I wouldn't care for some voids in some of the connections.
Best regards
Guenter
Guenter Grossmann
Swiss Federal Institute for Materials Testing and Research EMPA
Centre for Reliability
8600 Duebendorf
Switzerland
Phone: xx41 1 823 4279
Fax : xx41 1823 4054
mail: [log in to unmask]
---------------------------------------------------------------------------------
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF TECHNET
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------