Rigid Flexible PCB for High-Reliability Electronics

A flexible PCB is commonly called an FPC (Flexible Printed Circuit). It is constructed on a flexible polyimide substrate, allowing it to bend, fold, and conform to complex shapes. When combined with rigid PCB sections, the result is a rigid-flex PCB — a more advanced construction used in high-reliability, space-constrained electronic assemblies.

SFX PCB's rigid-flex boards support up to 20 total layers, including up to 12 flexible layers. This multilayer capability enables complex signal routing, dedicated power and ground planes, and impedance-controlled traces — making them suitable for high-speed digital, RF, and high-density interconnect applications in aerospace, medical, and telecom sectors.

Rigid-flex PCBs use polyimide (PI) for the flexible sections due to its excellent thermal stability and bendability, and FR4 for the rigid sections for structural support. Premium builds may incorporate Rogers materials for high-frequency RF performance. Supplier-qualified materials including Shengyi, DuPont, and Taiflex are used to ensure consistent quality.

Available surface finishes include ENIG (Electroless Nickel Immersion Gold), OSP (Organic Solderability Preservative), HAL Lead-free, Immersion Silver, Immersion Tin, ENEPIG, Soft Gold, and Gold Plating. ENIG is popular for fine-pitch components and long shelf life, while HAL Lead-free is chosen for RoHS-compliant applications.

SFX PCB's rigid-flex boards are manufactured under ISO 9001:2015 and ISO 14001:2015 certified quality management systems, with IPC Class II and IPC-A-610 Class 2/3 inspection standards applied. Each board undergoes electrical testing, impedance testing, AOI, and dimensional inspection before shipment, ensuring consistent quality for mission-critical applications.

Rigid-flex PCBs are used across aerospace and defense (radars, guidance systems), medical devices (defibrillators, hearing aids, ultrasound), automotive (ABS systems, dashboards), telecommunications (smartphones, base stations), industrial automation, and consumer electronics. Their ability to reduce weight, eliminate connectors, and fit into complex 3D enclosures makes them ideal for demanding, space-constrained designs.