The "standard" via fill for awhile was DuPont's CB100 silver based conductive via fill. The product has both good electrical and thermal conductivity. Most apps, though, need neither. You might think the conductive via fill could eliminate a plating step, but apparently the capability to get reliable contact from the via fill material to the copper is not there at this time. The CB100 is known for creating uneven surface finishes in the final product, which I believe is due to the uneven etching of the material during de-smearing processes. Over the years, non-conductive via fills have been developed which lead to more planar surfaces. And with the price of silver nowadays, the cost is cheaper. So I'd recommend you specify non-conductive fill unless you absolutely must have the thermal or electrical resistance properties the conductive fills can give you. Wayne Thayer >>> [log in to unmask] 6/12/2006 2:40 pm >>> Technet, The terms "Conductive" vs "NonConductive" came up in a discussion of a blind/buried via fab today and these were new terms to me relative to a PWB. Can anyone provide a brief definition of this or point me to something that explains it in terms of a fab. Unfortunately, the person that made the statement was more of a procurement person that was quoting specs, but did not really have an explanation of the requirement or difference. Is this an industry standard (new) term associate with PWB requirements, or is this just something someone used and its been passed on. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- DJT --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------