Five-Stage Laser-Drilled HDI PCB

An 18-layer high-multilayer HDI PCB built with five sequential laser-drill stages, hybrid stackup of TUC TU-883 cores plus Rogers RO4450F bonding film, 2±0.2mm thick with ENIG finish. The dielectric is 200um per stage with 0.20mm laser via diameter, resin-plug filled, and minimum via copper of 18um (average 20um). Five-stage construction stacks blind via levels across five lamination cycles, allowing extreme pin-escape density under fine-pitch BGAs that mechanical drilling cannot reach. The TU-883 plus RO4450F hybrid combines high-speed digital performance with controlled-impedance RF behavior, suiting boards that mix multi-Gbps SerDes with millimeter-wave front-ends. Used in 5G radio units, switch fabric line cards, AI inference and training accelerators, advanced FPGA boards, satellite payloads and other dense high-frequency designs.