Delay-Matching Routing for Advanced Packages

As advanced package technology evolves, design scales are rapidly expanding, and routing rules are becoming more complex, including any-angle routing and non-default wire spacing. Moreover, as high-speed applications advance, strict timing specifications for packages have become crucial, making delay matching an important consideration. In printed circuit board (PCB), the delay-matching problem has been well studied, but no previous work has addressed this problem in advanced packages, which involves complex routing rules and increased congestion, resulting in high computation cost. In this paper, we propose a novel solution for the delay-matching problem in advanced packages by integrating commonly used patterns-accordion, trombone, and sawtooth-with a gridless routing. These popular patterns are used to adjust trace lengths while maintaining signal integrity. Our approach incorporates delay-matching awareness during the global routing stage to alleviate congestion in dense routing groups. In post-detailed routing, we utilize a sliding window-based method to detect DRV-free regions for detouring and propose a redistributed method to avoid congestion in parallel bus routing. Lastly, we develop a shape-based pattern routing method to obtain the routing result and fine-tune acute-angle wires for better manufacturability. Experimental results demonstrate the robustness and effectiveness of our proposed algorithm. Our approach is workable for PCB as well.