Single-Tube Characterization Methodology for Experimental and Analytical Evaluation of Carbon Nanotube Synthesis

The existing evaluations of the semiconducting/metallic properties of carbon nanotube (CNT) synthesis do not take into account CNT variation and simply characterize the material with only one parameter psemi: the percentage of semiconducting CNTs. Specifically, this psemi figure of merit does not consider intermediate-on–off-ratio CNTs (semiconducting CNTs with poor Ion/Ioff), and yet, such CNTs can have a large impact on device- and circuit-level performance. Inspired by the complementary metal–oxide–semiconductor (CMOS) community, we address this inadequacy by considering intermediate-on–off-ratio CNTs and other CNT variations by offering a holistic view of CNT characterization through parameter distributions. In this paper, a new methodology, called single-tube characterization (STC), is presented, which directly observes and evaluates the distributions of CNT material properties. Such holistic distributions not only enable more accurate characterization and analyses of the material properties and variations, but they also further enable analyses to accurately predict performance and variation at the device- and circuit-levels.