Realization of Steep-Slope Transistor Using 1-D Gate-All-Around Carbon Nanotubes With Broken-Gap Source Structure

Carbon nanotubes (CNTs), as a 1-D material, have become a favorable material for replacing Silicon to continue Moore’s law. Herein, we propose a gate-all-around cold source FETs (CSFETs) with the broken-gap band alignment in the source region, which can break the Boltzmann limit by artificially constructing an isolated carrier density distribution window in energy. Furthermore, the introduction of metallic collapsed CNTs (CCNTs) through strain can achieve the reduction of tunneling barriers. Device simulations demonstrate that the bias voltage (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{d}$ </tex-math></inline-formula>) of CNTs-based CSFETs can be minimized to 0.3–0.4 V while satisfying the fundamental requirements of International Roadmap for Devices and System (IRDS). The minimum subthreshold swing (SS) can approach 20 mV/dec, and moreover, the scattering current can still achieve approximately 90% of the theoretical value, demonstrating the exceptionally high ballistic transport efficiency of CNTs. Those all are excellent prospects in low power consumption devices.