Novel Library of Logic Gates with Ambipolar CNTFETs: Opportunities for Multi-Level Logic Synthesis

This paper exploits the unique in-field controllability of the device polarity of ambipolar carbon nanotube field effect transistors (CNTFETs) to design a technology library with higher expressive power than conventional CMOS libraries. Based on generalized NOR-NAND-AOI-OAI primitives, the proposed library of static ambipolar CNTFET gates efficiently implements XOR functions, provides full-swing outputs, and is extensible to alternate forms with area-performance tradeoffs. Since the design of the gates can be regularized, the ability to functionalize them in-field opens opportunities for novel regular fabrics based on ambipolar CNTFETs. Technology mapping of several multi-level logic benchmarks — including multipliers, adders, and linear circuits — indicates that on average, it is possible to reduce both the number of gates and area by ∼ 38% while also improving performance by 6.9×.