Jim, I work for a company called ThermalWorks. We have developed a heat dissipating, thermal expansion controlled product called STABLCOR that is carbon based. NASA and the U.S. Air force helped fund the research. We use the same approach as Moon Man described, getting the stablcor layers as close to the surface of the board as possible. We can achieve a board CTE of 5-10 depending on how much STABLCOR we use. The advantages over CIC are: 1) Better thermal conductivity (600 - 900 W/m-k) depending on the grade of STABLCOR we use. Compared to CIC (160 W/m-k) 2) Lighter (2.20 g/cubic cm) vs. CIC (9.90 g/cubic cm) 3) Better CTE (-1.15ppm @20 degrees C) vs. CIC (4-5 @20 degrees C) 4) Stiffer (Young’s Modulus of 130 Msi) vs. CIC (19 Msi) These are raw material properties, but they give you a good idea of what STABLCOR can do when incorporated in a PCB. We are just going to market, which is why you probably have not heard about our product. If you want more info give me a call or send an email... Scott Kramer Sales Engineer ThermalWorks Inc. 714-960-5152 x203 [log in to unmask] --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------