Broadband characterization of low dielectric constant and low dielectric loss CYTUF™ cyanate ester printed circuit board material

Dielectric constant εr and broadband dielectric loss tan δ measurements were performed for the thermoplastic toughened cyanate ester printed circuit board CYTUF™ material. Characterization of tan δ over the 1-8 GHz frequency range was made using a simple short-pulse propagation technique. All the measurements were taken on four-metal-layer, 23 × 36 cm cards with representative transmission line structures. It was found the εr = 3.48 - 3.64 and tan δ = 0.0095 - 0.01, which are much lower than for standard FR-4 material. The impact of improved characteristics on wireability is analyzed through simulations of representative printed circuit board interconnections. © 1996 IEEE.