High Frequency, large format Ceramic Wiring Boards and MC;M-C substrates must exhibit the electrical properties of low dielectric constant low loss, and impedance control over the high frequency range. The goal of this work was to characterize the high frequency response of the low dielectric constant thick film system and determine whether the low dielectric constant system is a candidate materials system for fabrication of impedance controlled substrates. This paper compares the high frequency electrical performance of Low K ceramic silver and gold systems on large MCM-C substrates to organic Printed Wiring Board Laminates. The Time Domain Reflectometer (TDR) characterization pattern that was used for the gold and silver thick film materials was the same pattern used for PWB materials Impedance measurements of long traces in microstrip and stripline configurations were performed using that pattern by MIT Lincoln Laboratory, The thick film silver-compatible and gold-compatible dielectrics were compared to the PWB dielectric materials. Broadband frequency(1-12 GHz) dielectric constant and loss characterization of the material was further characterized using the T resonator technique. Materials and process improvements for higher yielding impedance controlled substrate fabrication were also determined in this work.
