Multiple chip planning for chip-interposer codesign

An interposer-based three-dimensional integrated circuit, which introduces a silicon interposer as an interface between chips and a package, is one of the most promising integration technologies for modern and next-generation circuit designs. Inter-chip connections can be routed on the interposer by chip-scale wires to enhance design quality. However, its design complexity increases dramatically due to the extra interposer interface. Consequently, it is desirable to simultaneously consider the co-design of the interposer and multiple chips mounted on it. This paper addresses the first work of chip-interposer codesign to place multiple chips on an interposer to reduce inter-chip wirelength. For this problem, we propose a new hierarchical B*-tree to simultaneously place multiple chips, macros, and I/O Buffers. An approach based on bipartite matching is then proposed to concurrently assign signals from I/O buffers to micro bumps. Experimental results show that our approach is effective and efficient for the codesign problem.