QCA-based nano circuits design [adder design example]

In order to design large digital circuits using quantum-dot cellular automata (QCA) cells, CAD tools and automated design methodology for QCA circuits are essential. This paper presents a QCA circuits design methodology based on traditional CMOS circuit design flow. This QCA circuit design methodology utilizes the current CMOS circuit design tools such as HSPICE and Synopsys design compiler. The QCA cell SPICE model is built for timing checking and accurate simulation. The basic QCA layout algorithm is developed for placing the QCA cells in the proper clock zones. A full adder design is shown as an example to demonstrate the whole design process.