Variation Aware Routing for Three-Dimensional FPGAs

To maximize the potential of three-dimensional integrated circuit architectures, 3D CAD tools must be developed that are on-par with their 2D counterparts. In this paper, we present a statistical static timing analysis (SSTA) engine designed to deal with both the uncorrelated and correlated variations in 3D FPGAs. We consider the effects of intra-die and inter-die variation. Using the 3D physical design tool TPR as a base, we develop a new 3D routing algorithm which improves the average performance of two layer designs by over 22% and three layer designs by over 27%. To the best of our knowledge, this is the first physical design tool to consider variation in the routing and timing analysis of 3D FPGAs.