Practical Routability-Driven Design Flow for Multilayer Power Networks Using Aluminum-Pad Layer

• Published in: IEEE transactions on very large scale integration (VLSI) systems Vol. 22; no. 5; pp. 1069 - 1081
• Main Authors: Chang, Wen-Hsiang, Chao, Mango C.-T, Chen, Shi-Hao
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.05.2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aluminum; Computer networks; Construction; Electro-migration (EM); Estimation; IR drop; Metals; Multilayers; Networks; Nonhomogeneous media; Placement; power network; Rails; Resistance; Routing; Routing (telecommunications); routing-driven; Very large scale integration; Wires; IR drop; power network; routing-driven; Electro-migration (EM)
• ISSN: 1063-8210; 1557-9999
• DOI: 10.1109/TVLSI.2013.2264686

This paper presents a novel framework to efficiently and effectively build a robust but routing-friendly multilayer power network under the IR-drop and electro-migration (EM) constraints. The proposed framework first considers the impact of the aluminum-pad layer and provides a conservative analytical model to determine the total metal width for each power layer that can meet the IR-drop and EM constraints. Then the proposed framework can identify an optimal irredundant stripe width by considering the number of occupied routing tracks and the potential routing detour caused by the power stripes without the information of cell placement. Next, after the cell placement is done, the proposed framework applies a dynamic-programming approach to further reduce the potential routing detour by relocating the power stripes. A series of experiments are conducted based on a 40 nm, 1.1 V, and 900-MHz microprocessor to validate the effectiveness and efficiency of the proposed framework.