TABLE OF CONTENTS Carbon nanotubes (CNTs) of different forms and shapes are the most studied nanomaterials because it is hoped that either the electrical or the optoelectronic devices based on them will exceed the performances of similar devices based on Si and GaAs semiconductors. The CNT-based electrical devices are studied in this chapter, while the corresponding optoelectronic devices will be presented in Chapter 6. Before detailing various CNT-based electrical devices we analyze their physical properties, which reveal astonishing behaviors never encountered before in any known material.
The CNTs, as well as the electronic, optical, and NEMS (nano-electro-mechanical systems) devices based on them, represent one of the most studied topics in modern nanoelectronics. Theoretical, experimental and advanced technological processes are involved in the study of CNT properties and applications. CNTs have a series of amazing electrical, thermal, optical, or mechanical characteristics, which are either not encountered in other materials or prevail over similar characteristics of any existing material with few orders of magnitude. These properties justify the huge interest in CNT devices.
CNTs are empty cylinders, which can be viewed as rolled up sheets of a single or several concentric layers of graphene. As displayed in Figure 3.1, the graphene is a 2D honeycomb structure of sp 2 carbon atoms. The CNT with a single rolled up sheet of graphene is called single-walled CNT (SWCNT), while the CNT having several concentric graphene layers is termed multiwalled CNT (MWCNT). Very often the physical properties of...
