8-Layer Rigid-Flex Board

An 8-layer rigid-flex PCB combining 8 rigid layers and 2 flex layers, with 1-stage HDI build-up on the rigid sections. The construction places dense multilayer routing and HDI microvia density where high-speed processors, RF front-ends, and fine-pitch BGAs require it, while the 2-layer flex bridge replaces inter-board cables and folds inside compact enclosures. This topology fits modular handheld products, foldable consumer devices, smartwatch main boards with active radio, and high-density telecom subassemblies that integrate baseband and front-end into one folded mechanical assembly. Manufacturing involves sequential lamination of the HDI stack, selective adhesive bonding of the flex layers, controlled-depth drilling, and precise registration to maintain bend reliability and impedance control across production volumes.