Originally published at: https://www.protoexpress.com/blog/designing-fabricating-uhdi-pcbs/
Ultra-HDI PCBs are becoming essential in high-speed applications such as AI systems, where circuit density and signal integrity are critical. As operating frequencies go beyond 25 GHz, even small variations in line width, spacing, and impedance can lead to significant signal losses. UHDI technology supports extremely fine features and tight tolerances, making it possible to maintain signal quality while accommodating the dense routing and component demands of advanced systems. Highlights: Ultra-HDI PCBs use ultra-fine features, with trace and space dimensions of 2 mil or less. They rely on advanced structures like laser-drilled microvias, via-in-pad connections, and thin dielectrics instead of…