Tiny nano-scale junction built on B/N doped single carbon nanotube

Abstract

The characteristic sizes of carbon nanotube (CNT)-based devices are constantly being reduced. However, this continuing miniaturization is still facing many problems and requires innovative ideas and structures. By regular doping of boron and nitrogen atoms in a semiconducting single-wall carbon nanotube (SWCNT), we have constructed a nano-scale junction with rectifying characteristics. The I–V curve of our junction resembles the I–V curve of an ideal diode with a p-n junction. This junction channel is about 0.6 nm wide and 3.4 nm long, and the footprint is 5.1 nm long. Under a 0.5 V bias, the junction has a leakage current of −8.8 × 10−3 μA, a rectifying ratio Ion/Ioff of 0.716 × 103, and a current density of 10.52 mA μm−1. Our study also shows how different dopant distributions influence the I–V curve. Such a regular nano-scale doping method is effective and important, compared with the traditional random doping method.