Most proposed nanoscale computing architectures are based on a certain type of two-level logic family, e.g.,AND–OR, NOR–NOR, NAND–NAND, etc. In this paper, a new fabric architecture that combines different logic families in the same nanofabric is proposed for higher density and better defect tolerance. To achieve this, we apply very minor modifications on the way of controlling nanogrids, while the basic manufacturing requirements remain the same. The fabric that is based on the new heterogeneous two-level logic yields higher density for the applications mapped to it.

Emerging nano-device based architectures will be impacted by parameter variation in conjunction with high defect rates. Variations in key physical parameters are caused by manufacturing imprecision as well as fundamental atomic scale randomness. In this paper, the impact of parameter variation on Nanoscale Cognitive Computing Fabrics is extensively studied through a novel integrated methodology across device, circuit and architectural levels. This integrated approach enables to study in detail the impact of physical parameter variation across all fabric layers.

Various fault-tolerance techniques have been proposed in recent years to tolerate the high defect rates expected in emerging nanofabrics with unconventional nano-manufacturing techniques. The proposed techniques include modular redundancy schemes that use majority voters to vote on the ‘0’ or 1’ outputs of redundant modules. Novel nanoscale computational fabrics employ new circuit and logic styles where the likelihood of occurrence of faulty ‘1’s and faulty ‘0’s may not be identical. This provides an opportunity for using biased voting (towards logic ‘1’ or ‘0’) to achieve improved yield.

High defect rates are associated with novel nanodevice-based systems owing to unconventional and self-assembly based manufacturing processes. Furthermore, in emerging nanosystems, fault mechanisms and distributions may be very different from CMOS due to unique physical layer aspects, and emerging circuits and logic styles. Development of analytical fault models for nanosystems is necessary to explore the design of novel fault tolerance schemes that could be more effective than conventional schemes.