A Holistic Approach to Characterize Signal Vias in Anisotropic PCB Substrates for PCIe Gen6

The development of PCI Express (PCIe) Gen6 exhibits several significant design challenges, primarily in achieving the targeted data rate of 64 GT/s per lane while maintaining signal integrity and reliability. The design of Printed Circuit Boards (PCBs) necessitates meticulous attention to material selection, trace layout, and the small but crucial element, via design. Improperly designed vias can cause signal reflections and impedance mismatching that compromise data transmission in signal layer transition. This paper follows a unique holistic approach to design high-speed differential vias for signal interconnect based on anisotropic PCB laminate properties. Measurement and simulation results show great correlations, and via design is further optimized for PCIe Gen6 success.