6-Layer Any-Layer Rigid-Flex Board

A 6-layer any-layer rigid-flex PCB built on IF-2LD flex laminate combined with R-1551WN rigid material, with 0.75±0.10mm overall thickness and ENIG surface finish. Any-layer interconnect via stacked microvias allows direct routing between any pair of layers, removing the conventional through-hole stub and freeing routing channels under fine-pitch components. The thin profile and integrated flex bridge make this board suitable for foldable consumer devices, smartwatches, hearables, and compact IoT modules where 3D packaging is needed. Manufacturing combines laser-drilled microvias, sequential lamination across rigid and flex sections, and copper plating optimized for high-aspect-ratio fill. The result is a high-density, bend-tolerant substrate that replaces multi-board assemblies and FPC-to-board connectors, reducing system thickness and improving signal integrity in mobile and wearable applications.