Mike, Just to make obvious what others have already said. The microvia will not thieve an appreciable amount of solder if at all. ALL soldered microvias, I have cross sectioned so far, did have a tiny void in the solder joint that filled the microvia. Certainly not big enough to get up tight about. Thanks Ryan Grant Advanced Technology Engineer MCMS (208) 898-1145 [log in to unmask] > -----Original Message----- > From: Michael Forrester [SMTP:[log in to unmask]] > Sent: Thursday, March 08, 2001 2:25 PM > To: [log in to unmask] > Subject: [TN] MicroVia In Pad Vs Silver VIA fill > > We currently have a design with 15 X 15 array BGA patterns a 12 layer > 0.62 bd. > There are 10 mil vias in every BGA pad (22 mil pad) . > The reason for the Via in pad is keep the runs as short as possible. > Currently > we fill the vias with conductive silver epoxy and plate E Ni/I Au > over the entire pad surface. I would like to try a microvia in pad, no > via > fill, and OSP. My questions are: > > 1) Can I get away with not filling the microvia to prevent > solder > thieving? > 2) Are there any problems with this approach? If NG, other > ideas to > get rid of silver fill? > 3) Is there any disadvantage/reliability risk, to using silver > via > fill other than cost and longer lead time? > > Thank you in advance. > > Best Regards, > > Michael Forrester > > -------------------------------------------------------------------------- > ------- > 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 > To temporarily halt delivery of Technet send the following message: SET > Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > > E-mail Archives > 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 > -------------------------------------------------------------------------- > ------- --------------------------------------------------------------------------------- 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 To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives 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 ---------------------------------------------------------------------------------