Novel low-loss resin coated copper and core material for advanced IC packags

The implementation of 5G technology is expanding well beyond traditional mobile phone applications and paving the way for the internet of everything (IoE). Sustained deployment of high-speed communication systems is contingent on the utilization of higher frequencies and wider bandwidths. For IC packaging designs, these trends mandate higher signal speeds and lower transmission losses. Hence, leading-edge communication modules require chip substrates with better electrical performance, finer traces, and thinner layers to enhance signal speeds. In addition to low transmission loss characteristics, assembly-level reliability is becoming increasingly important for IC substrate materials. A promising option for creating, high-performance, multi-layer substrates is the use of a resin-coated copper foil (RCC) construction to create thinner routing layers on one or both sides of a core material. The RCC approach eliminates glass-cloth in the insulation material, enabling thinner layers. One of the primary requirements for successful implementation of this approach is the development of a complimentary substrate material. Toward this objective, the researchers developed a new highly temperature resistant, ultra-low dielectric system based on a unique Polyphenylene Ether (PPE) polymer which exhibits excellent dielectric properties and enables high-density multi-layer substrate constructions, including fine via pitches and very thin circuit layers. This paper describes the formulation development, as well as testing on mechanical and electrical properties, multi-layer formation, manufacturability, and reliability of substrate test vehicles made with this resin system.