ABSTRACT
This chapter focuses on the application of carbon nanotubes as a channel material for building carbon nanotube field-effect transistors (CNFETs) because of their potential of providing large performance advantage over silicon complementary metal oxide semiconductor devices. The variation in the diameter of tubes results in a variation in the drive current of CNFET, and therefore impacts the performance of CNFET-based circuits. The chapter analyzes the impact of diameter variation and the presence of metallic tubes on the functional yield of CNFET-based logic gates. The major challenges faced by the CNFET technology are variation in the diameter of tubes, misalignment of CNTs during the fabrication of CNFETs, and the unwanted growth of metallic tubes. The percentage of metallic tubes falls roughly into two ranges: a range for which robust CNT-based circuits can be implemented with circuit-level techniques, and a range for which extra processing techniques are required to remove the metallic tubes.
