Fabrication and Characterization of Ideal Nanoprobes and Sources of Electron and Ion Beams

  • Ahmed Ali

Student thesis: Master's Thesis

Abstract

The remarkable advances in ultra-high resolution microscopy have enabled researchers to fabricate, manipulate and characterize materials at nano and atomic scales. Ultra-sharp tips with an apex radius in the range of a few nanometers (usually called nanotips) are the key tools required to optimize the characterization capability of scanning probe microscopes and electron microscopes. Therefore, nanotips fabrication has been receiving significant research attention over the last two decades and thus several techniques have been developed to fabricate nanotips that terminate with a single atom (referred to as single atom tips (SATs)). In this work we fabricate and characterize nanotips and SATs using a recent method, which is referred to as the local electron bombardment method. This method uses an innovative physical approach that will improve the production of nanotips and overcome several obstacles faced by the previous methods. This research aims to experimentally fabricate nanotips by this new method using a home-made Field Ion Microscope (FIM). It also aims to investigate the electrical and structural characteristics of the produced nanotips and SATs. This involves modelling the atomic structure of the nanotip apex and the overall nanotip shape at a microscopic scale, utilizing computer programing and finite element simulation tools. We also perform electrical characterization of the produced nanotips by measuring the current-voltage (I-V) characteristic and analysing the field emission beams from the SATs.
Date of AwardMay 2016
Original languageAmerican English
SupervisorMoh'D Rezeq (Supervisor)

Keywords

  • Nanotip
  • Characterization
  • Fabrication
  • Modeling
  • Simulation.

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