Very-large-scale-integration of complementary carbon nanotube field-effect transistors

Abstract

Electronics is approaching a major paradigm shift as silicon transistor scaling no longer yields historical energy-efficiency benefits, spurring research towards beyond-silicon nanotechnologies. In particular, carbon nanotube field-effect transistor (CNFET)-based digital circuits promise substantial energy-efficiency benefits, but the inability to (1) fabricate complementary metal-oxide-semiconductor (CMOS) CNFET circuits that integrate both PMOS and NMOS CNFETs and (2) perfectly control intrinsic nanoscale defects and variability in carbon nanotubes has precluded the realization of very-large-scale integrated CMOS systems. Here we propose and experimentally demonstrate a comprehensive manufacturing methodology for CNTs, which encompasses a set of original processing and circuit design techniques that are combined to overcome all of these intrinsic CNT challenges (variability, manufacturing defects, and material defects) across full industry-standard large-area substrates. As a demonstration of the feasibility of implementing this manufacturing methodology, we experimentally demonstrate the world's first microprocessor built from a beyond-silicon emerging nanotechnology: RV16X-NANO. This 16-bit microprocessor is based on the RISC-V instruction set, runs standard 32-bit instructions on 16-bit data and addresses, comprises more than 14,000 CMOS CNFETs and is designed and fabricated using industry-standard design flows and processes. This work is a major advance for carbon nanotube-based electronics, and more broadly experimentally validates a promising path towards realizing practical next-generation beyond-silicon electronic systems.