RAM Design Using Quantum-Dot Cellular Automata

Quantum-dot cellular automata (QCA) is a novel and potentially attractive technology for implementing computing architectures at the nano-scale. By applying a set of simple layout rules, arbitrary circuits can be made using QCA cells. In this work, we describe the design and layout of a QCA random access memory (RAM), showing the layout of individual memory cells, as well as, a suggested layout for a 1x4 RAM. The RAM is based on a 2D grid of row addressable memory cells. Each of the memory cells in the RAM uses 158 QCA cells. Assuming that we can fabricate cells which are separated by 10nm, memory capacities of over 1.6 Gbit/cm can be achieved. Simulations on the proposed memories were carried out using QCADesigner, a layout and simulation tool for QCA, by iteratively applying an intercellular Hartree-Fock approximation.