CD3D: A Constraint-driven 3-dimensional Router for Thick Film Mcms

Abstract

Physical design is currently a bottleneck in widespread use of MCMs. In particular, routing of a complex MCM while satisfying several performance, electrical and manufacturing constraints is a challenging problem. A router for thick film MCMs is presented in this paper. This will router partitions the whole MCM routing space into a set of small towers and decompose the routing process into three phases, viz, routing distribution, terminal assignment, and tower routing. The router has three fundamental features. First, it maintains the 3-dimensional characteristics of the original problem while partitioning it into several smaller problems and as a result, it can achieve the best utilization of the routing space. Second, it is designed to meet the constraints of net-length, path-separation, parallel-path-length, and the number of stacked vias and thus can satisfy the design requirement of high performance MCMs. Finally, the approach is amiable to parallel processing which can be used to improve the time complexity and memory constraints in a parallel computing environment. Experimental evaluation confirms the validity of our approach.