Quantum-dot Cellular Automata Placement and Routing with Hierarchical Algorithm

To meet the needs of the market launch, placement and routing(P&R) algorithms for conventional circuits have started to adopt a hierarchical design, divide and conquer philosophy for the layout of VLSI circuits. Quantum-dot cellular automata (QCA) circuits are considered a solution to overcome the limitations of Moore’s Law. However, the current automated design of QCA circuits is still in its preliminary stages. This paper uses a hierarchical structure, which borrows from traditional circuits that should be laid out in large-scale circuits, to hierarchically process QCA circuits, laying them out layer by layer while using the A* algorithm for wiring to find feasible solutions. The algorithm is implemented using the C++ programming language, and simulation results verify the correctness of the algorithm.