Hi Dave, Here are some references: [1] Engelmaier, W., “Achieving Solder Joint Reliability in A Lead-Free World, Part 2,” Global SMT & Packaging, Vol. 3, No. 8, August 2007, pp. 44-46. [2] Okinaga, N., et al, (Sekisui) “Excellent Reliability of Solder Ball Made of a Compliant Plastic Core,” 2001 IEEE Electronic Components and Technology Conf., 2001, 5 pages. [3] Klein, M., et al, (Fraunhofer Institute) “A Characterization of Plastic Core Solder Balls for BGA and flip Chip Applications,” 2002 IMAPS Nordic Conf., 2002, 6 pages. [4] Yoon, S., et al, (Hyundai) “CSP Board Level Reliability Testing of Pb-Free Sn-Ag-X (X=Cu, In) and Polymer-Core Solder Ball,” Proc. 6th Annual Pan Pacific Microelectronics Symp., Kauai, Hawaii, February 2001, 9 pages. [5] Movva, S., et al, (Kyocera) “High Reliability Second Level Interconnects Using Polymer Core BGAs,” 2004 IEEE Electronic Components and Technology Conf., 2004, pp. 1443-1448. I will send you a copy of Ref. 1 by separate mail. To my knowledge, Kyocera is selling them. Here are 2 e-mail addresses: [log in to unmask], [log in to unmask] Werner ************************************** See AOL's top rated recipes (http://food.aol.com/top-rated-recipes?NCID=aoltop00030000000004) --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 -----------------------------------------------------