What a coincidence, this months edition of "Printed Circuit Fabrication" magazine (miller freeman / www.pcfab.com) has done a 2.5 page article on the same subject. It mentions several references that I can re-type if you wish, however the only standard that gets mentioned is ANSI/IPC-EG-140 1988 (although I could not find it mentioned in the text). >-----Original Message----- >From: Stephen R. Gregory [SMTP:[log in to unmask]] >Sent: Friday, May 28, 1999 5:52 AM >To: [log in to unmask] >Subject: Re: [TN] Hollow fibers > >In a message dated 5/27/99 8:59:20 PM Pacific Daylight Time, >[log in to unmask] writes: > >> Thank you for the information. Have you heard of hollow fiber and any spec >> or standard for that? > >Hi there, > >While I'm no laminate guru, my "doggie" did turn-up these two leads: > >Hollow Fibers in Woven Laminates >A. Shukla, T. Dishongh, M. Pecht, and D. Jennings >Printed Circuit Fabrication, Vol. 20, No. 1, January 1997 >------------------------------------------------------------------------ >ABSTRACT: > >Electronic packaging substrates with fine-line circuitry, such as those used >in laminated multichip modules (MCM-L) and plastic ball grid arrays (PBGAs), >are generally fabricated with layers of copper clad composite laminates. The >conducting copper provides electrical interconnections and power distribution >for the system, while composite laminates furnish mechanical support for the >structure along with insulative resistance. > >Most laminates are comprised of several plys of glass fabrics embedded in a >polymeric resin, where the fabric acts as a structural reinforcement by >offsetting the resin's inherent mechanical and thermomechanical weaknesses. A >popular fabric fiber material used in the electronics industry for laminate >reinforcement is E-glass due to cost high strength, water resistance, and >bond stability with resins. > >***************************************************************************** >* >************** > >Hollow Fibres in PCB, MCM-L and PBGA Laminates May Induce Reliability >Degradation > >A. Shukla, M. Pecht, J. Jordan, K. Rogers, and D. Jennings >Circuit World, Vol. 23, No. 2, 1997 >------------------------------------------------------------------------ >ABSTRACT: > >The presence of hollow fibres in laminates used in printed circuit boards, >multichip module laminated substrates and plastic ball grid arrays has a >potentially significant impact on reliability. Hollow fibres are vacuous >glass filaments in E-glass laminate reinforcements and are seen as a >reliability problem since they can provide paths for failure mechanisms such >as conductive filament formation. This paper discusses the manufacture of >woven fabric laminates and the cause of hollow fibres Experiments conducted >to assess the occurrence of hollow fibres in laminates are then presented >long with the key reliability issue. > > > >So try and find some way to get your hands on those articles and you may find >out what you need.... > >-Steve Gregory- > >################################################################ >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 ################################################################ ################################################################ 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 ################################################################