The main difference from a component perspective is that most PBGA's have
solder balls which are .030 inch diameter and are made up of Sn63 Pb37 (aka
"eutectic solder").  The common Ceramic BGA's have solder balls which are
.035 inch diameter and made up of Sn10 Pb90 (aka "high lead solder").  The
high lead solder balls are attached to the component with Sn63 Pb37 or a 2%
silver bearing version of the same.

Because of the high lead balls, the ceramic bga's are not as forgiving as
the PBGA's when it comes to self alignment.

Since the high lead balls do not reflow in the process, the standoff of .035
inches is maintained regardless of the weight of the package.  The key
reason behind the high lead solder balls is the increased standoff and the
natural ductility of the high lead material which helps reduce joint strain
which comes from mounting a low thermal expansion ceramic on a high thermal
expansion FR4 board.
Motorola has published some good papers on CBGA.  One of the papers I have
seen goes into detail as to how much solder paste (in cubic mils) is
required for a proper joint.  If I can find this paper on Motorola's web
site I will post a link on TechNet.

Hope this helps

Russ Winslow
[log in to unmask]


-----Original Message-----
From: Edwin Maximo <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Thursday, October 01, 1998 7:30 PM
Subject: [TN] Types of BGAs


Hi all,
        I'm doing some research regarding BGA.Can someone tell me what's the
main difference between a Plastic BGA from a Ceramic BGA (except for
their substrate). How are they placed in PCBs, and what
considerations are involved in it. Are there any internet sites where
I can have some information about this topic.  Any information will
be appreciated. Thanks



Regards,
Edwin Maximo
Value Engineer
Electronic Assemblies Inc. Phils.
email: [log in to unmask]

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following
text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section
for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or
847-509-9700 ext.312
################################################################

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet 
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################