4 Layer Flexible PCB Production Record #FPC-20260821-065

We manufactured five panels of this 4-layer flexible PCB with dimensions of 111.25 × 16.75 mm and an overall thickness of 0.2 mm, utilizing 1/3 oz rolled copper. PI stiffeners provided selective reinforcement while yellow soldermask, white silkscreen, and immersion gold ENIG surface finish completed the stackup. Material preparation and polyimide handling received close attention to preserve the thin flexible laminate during layer stack alignment and high-pressure lamination, ensuring registration remained within tolerance across the multilayer construction.

Circuit imaging and etching produced the 6/6 mil traces without issue, after which FPC coverlay lamination and solder mask application were sequenced to match the dynamic requirements of the design. Electroless nickel deposition and immersion gold deposition followed, preparing the boards for dynamic flex testing that verified endurance under repeated bending cycles. Full electrical testing confirmed net continuity and isolation on every panel.

The complete sequence, spanning 14.2 days from engineering review to final shipment, delivered consistent quality that aligned with all specified parameters for this low-volume flexible circuit order.