4 Layer FR4 PCB Production Record #FR4-20260104-016

This production record covers a standard 4-layer FR4 PCB fabricated with immersion gold ENIG surface finish. The boards measured 1.6 mm in thickness with 1 oz copper weight on all layers and maintained a conventional minimum track and spacing of 6 mil. These parameters allowed for straightforward yet precise processing through our established workflow, beginning with engineering review and material preparation to verify all incoming materials.

Inner layer imaging established the internal circuitry, followed by circuit imaging and etching for the outer layers. Layer stack alignment received close attention prior to high pressure lamination, ensuring excellent interlayer registration. Solder mask application prepared the surfaces for electroless nickel deposition and immersion gold deposition, delivering a flat pad finish known for its excellent solderability and long shelf life.

Final electrical testing verified continuity and insulation resistance across the full batch. The complete cycle took 4.2 days from start to finish, resulting in panels that exhibited uniform quality and reliable performance characteristics.