Tuning semiconducting properties of single carbon nanotube for fabrication of nano devices

Abstract

Carbon nanotube (CNT) is found to be an amazing material for nanotelectronics due to its unique properties. It provides the possibility of miniaturizing the traditional electronic elements. Recently, people have been focusing on exploring its applications on optoelectronics because CNT is a direct bandgap material and its bandgap is inversely related to its diameter. Thus, it is ease for photon adsorption or generation with different wavelengths. In this paper, we presented the modification of the diameter of a single multi-walled carbon nanotube (s-MWNT) by electrical breakdown of nanotube walls. Thus, the conduction mechanism of the single carbon nanotube (s-CNT) can change from conducting to semi-conducting. Also, the barrier height of the s-CNT based diode which is fabricated by using Atomic Force Microscopy based nanomanipulation system, can be indirectly modified, which has the same effect from CNT doping. The breakdown of a MWNT was investigated using Atomic Force Microscopy (AFM) and the diameter, changed from 60nm to ∼10nm, was measured at each step of breakdowns. Using this modification technique, the s-CNT based diode can potentially be used in optoelectronics. © 2006 IEEE.