Minority gate oriented logic design with quantum-dot cellular automata

This paper presents novel combinational logic designs with plus-shaped quantum-dot cellular automata (QCA) using minority gate as the fundamental building block. Present CMOS technology of VLSI design is fast approaching its fundamental limit, and researchers are looking for a nano-scale technology for future ICs in order to continue the pace of circuit miniaturization predicted by Moore's law even beyond 2016. QCA is considered to be a promising technology in this regard. This paper provides the fundamentals of QCA followed by the proposed QCA structure realizing a minority gate, given by the Boolean expression m (X-1, x(2), x(3)) = x(1)(').x(2)(+)(')x(2)(').x(3)(+)(')x(3)(').x(1)('). Universality of minority gate is established, and minority gate oriented design principles are provided. Minority gate oriented designs for XOR and full adder are presented. Simulation results show the effectiveness of the proposed designs.