PCB Capabilities
Rigid-Flex PCB Manufacturer
Integrated rigid and flexible sections replacing connectors and cables.
Rigid-flex PCBs integrate rigid multilayer sections and flexible polyimide sections into a single board, replacing connectors and cable assemblies with a unified construction that is lighter, more reliable and more compact. The rigid sections carry components and provide mechanical mounting points. The flex sections bend to connect rigid sections across three-dimensional enclosure geometries, fold flat for compact packaging, or flex dynamically during product operation. AstroPCB manufactures rigid-flex PCBs with polyimide flex zones, controlled impedance, and HDI features for medical devices, military electronics, aerospace avionics, consumer electronics and industrial instrumentation.
Rigid-flex construction
A rigid-flex board is fabricated as a single panel. The rigid sections consist of standard multilayer construction — FR-4 or high-Tg laminate with copper signal, ground and power layers. The flex sections use polyimide substrate with one or two copper layers that continue from the rigid sections through the flex zone. At the rigid-to-flex transition, the rigid laminate layers terminate and the flex layers emerge, protected by coverlay (polyimide film) instead of solder mask.
The layer count in rigid sections is typically higher than in flex sections. A common construction uses 8-12 layers in the rigid areas and 2 layers through the flex zones. Only the layers that carry signals or power between rigid sections need to continue through the flex — additional routing layers exist only within the rigid sections where they are needed.
Benefits over cable assemblies
Rigid-flex boards eliminate board-to-board connectors and the associated cable assemblies. Each eliminated connector removes a potential failure point (contact resistance degradation, vibration-induced intermittent connections, moisture ingress), reduces assembly labor (no cable cutting, stripping, crimping and plugging), saves space (connectors and cable routing consume volume), and reduces weight (cables and connectors are often heavier than the flex zone they replace). For products where reliability, size and weight are premium constraints — medical implants, military manpack radios, satellite subsystems, folding consumer electronics — rigid-flex provides measurable advantages over discrete cables.
Design considerations
Flex zone bend radius must accommodate the polyimide construction thickness and copper type. Single-layer flex with rolled annealed copper provides the tightest bend radius and best dynamic flex endurance. The rigid-to-flex transition requires staggered layer terminations, copper relief patterns and coverlay overlap to manage mechanical stress at the boundary. Impedance control through flex zones is achievable but requires careful stackup engineering because the flex zone dielectric differs from the rigid zone dielectric.
Cost is the primary constraint. Rigid-flex boards cost 3-5x more than equivalent rigid boards due to the additional materials, fabrication complexity and yield challenges. Justify rigid-flex when the connector and cable elimination provides genuine system-level benefits in reliability, size, weight or assembly cost — not simply for routing convenience.
Manufacturing capabilities
AstroPCB manufactures rigid-flex with up to 20 rigid layers and 4 flex layers, polyimide flex thickness from 25 to 100 microns, adhesiveless and adhesive-based flex constructions, stiffener application (FR-4, polyimide, stainless steel), controlled impedance through rigid and flex zones, and HDI features (microvias, via-in-pad) in the rigid sections. Every rigid-flex order includes an engineering review of the bend radius, transition design and stackup feasibility.
Request a rigid-flex quote
Upload design files with the rigid-flex stackup, bend radius requirements and layer count. The engineering team will review the construction for manufacturability and provide a DFM-verified quotation.