EFFECT OF DOPING ON GROWTH AND FIELD EMISSION PROPERTIES OF SPHERICAL CARBON NANOTUBE (CNT) TIP PLACED OVER CYLINDRICAL SURFACE

Abstract

ABSTRACT Research into Carbon Nanotube based field emission devices has made significant advances—both scientifically and technologically—during the last decade, and the first products will soon enter the market. Carbon Nanotubes as electron field emitters can be used in Field Emission Flat Panel Displays, Electron microscopes and other electron emitting devices. The efficiency and field emission capacity of the devices can be further enhanced by doping Carbon Nanotubes with hetro-atom such as Nitrogen. The effect of adding Boron on Carbon Nanotubes is also studied. In this thesis work we have theoretically investigated the effect of doping of hetero-atoms on the growth and field emission properties of Carbon Nanotubes (CNTs) tip placed over a cylindrical surface in complex plasma. The effect of doping elements of N and B on the growth of CNTs namely the tip radius has been carried out for typical glow discharge plasma parameters. A theoretical model incorporating kinetics of plasma species such as electron, ions and neutral atoms including doping elements like nitrogen (N) and Boron (B) and energy balance of CNTs in a complex plasma has been developed. It is found that N and B as doping elements affect the radius of CNTs extensively. We obtain small radii of CNT doped with N and large radius of CNT doped with B. The field emission characteristics from CNTs have therefore been suggested on the basis of results obtained. This calculation is done with the help of Mathematica 9.0 software.