RO4000® dielectric materials have long been used in combination with FR-4 cores and bondplys as a means to achieve a performance upgrade of standard FR-4 multi-layer designs. RO4003C™, RO4350B™, RO4360G2™, RO4835™, and RO4000 LoPro™ glass reinforced hydrocarbon/ceramic laminates have been used in layers where operating frequency, dielectric constant, or high-speed signal requirements dictate the need for high performance materials. FR-4 cores and bondply are still commonly used to inexpensively form less critical signal layers.

The RO4400™ bondply family is comprised of three grades based on the RO4000 series core materials, and are compatible in multi-layer constructions with RO4003C, RO4350B, RO4360G2, RO4835 or RO4000 LoPro laminates. A high postcure Tg makes RO4400 series bondply an excellent choice for multi-layers requiring sequential laminations as fully cured RO4400 bondplys are capable of handling multiple lamination cycles. In addition, FR-4 compatible bond requirements permit RO4400 bondply and low flow FR-4 bondply to be combined into non- homogeneous multi-layer constructions using a single bond cycle.

RO4450F™ bondply has demonstrated improvement in lateral flow capability over RO4450B™, and is becoming the first choice for new designs or as a replacement in designs that have difficult fill requirements. RO4460G2™

bondply provides designers with a 6.15 Dk bonding layer that, just as the other RO4400 bonding materials, exhibits excellent Dk control while maintaining a low z axis expansion for plated through hole reliability.

Each of the three grades of bondplys are recognized by Underwriter Laboratories with the UL-94 flame rating, and are compatible with lead-free processes.