Versatile Signal Distribution Networks for Scalable Placement and Routing of Field-coupled Nanocomputing Technologies

Abstract

Field-coupled Nanocomputing (FCN) is a promising beyond-CMOS technology that leverages physical field repulsion instead of electrical current flow to transmit information and perform computations, potentially leading to energy dissipation below the Landauer Limit and clock frequencies in the terahertz regime. Despite recent progress in the experimental realization of FCN using Silicon Dangling Bonds (SiDBs), the physical design of FCN circuits remains a challenging task due to different design constraints compared to CMOS technologies. In this paper, we present three core contributions to the FCN physical design problem, building on top of the fastest heuristic algorithm in the FCN literature, ortho. Via special routing structures called Signal Distribution Networks (SDNs), we 1) reduce area overhead, wire costs, and the number of wire-crossings in routing solutions by approximately 25%, 10%, and 17%, respectively; 2) allow the use of Majority gates to quantify their routing costs, which occur to be immense; and 3) enable the automatic placement and routing of sequential logic for the first time in the literature. Our approach can potentially pave the way for the practical implementation of the FCN technology and its advancement as a viable green alternative to conventional computing technologies.