Testing of quantum cellular automata

There has been considerable research on quantum dot cellular automata (QCA) as a new computing scheme in the nanoscale regimes. The basic logic element of this technology is the majority voter. In this paper, a detailed simulation-based characterization of QCA defects and study of their effects at logic level are presented. Testing of these QCA devices at logic level is investigated and compared with conventional CMOS-based designs. Unique testing features of designs based on this technology are presented and interesting properties have been identified. A testing technique is presented; it requires only a constant number of test vectors to achieve 100% fault coverage with respect to the fault list of the original design. A design-for-test scheme is also presented, which results in the generation of a reduced test set at 100% fault coverage.