Semi-Flex PCBs

Semi-flex PCBs use specialized FR-4 materials and a specific manufacturing method to create a flex-to-install design that can provide an economical solution for certain applications.

Please contact your local NCAB Group company if you need further information or assistance, we are happy to help you.

Semi-Flex PCBs – Technical specification

FeatureNCAB´s technical specifcation
Number of layers1 – 12 layers, with 1 – 2 conductive layers in bending area.
Technology highlightsThe process uses controlled depth routing of the FR-4 to achieve a flexible / bending section within a traditionally rigid FR-4. Only suitable for static operations – bends typically just for installation. A lower cost solution for some very specific “flex-to-fit”applications.
Bending performance50 x bend cycles of 0° – 90° – 0°
Bend features5mm radius / max bending angle 90°
MaterialsSpecialized FR-4 for static flex applications
Copper weights (finished)35μm
Minimum track and gap0.075mm / 0.075mm
PCB thickness1.00mm – 2.00mm
PCB thickness in flex section0.25mm ± 0.05mm
Maxmimum dimensions538mm x 610mm
Surface finishes availableHASL (SnPb), LF HASL (SnNiCu), OSP, ENIG, Immersion tin, Immersion silver, Electrolytic gold, Gold fingers
Minimum mechanical drill0.20mm

What is the difference between semi-flex and rigid flex?

Semi-flex is effectively a ‘standard’ multilayer PCB, built using specific types of FR4 that has been depth to a specific tolerance so that the resulting thinner area provides a flexible / bending section of the traditionally rigid FR4.
Semi-flex is suitable for static applications (flex to install), or with very limited number of bends.

Difference between semi-flex and rigid-flex PCBs

Download our design guidelines for Semi-Flex PCBs

To prevent getting it wrong from the start, we have put together our design guidelines, to use as a checklist.