Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)

In recent years, two-dimensional (2D) materials like Graphene and Hexagonal Boron Nitride (h-BN) have been generating considerable interest due to their many outstanding properties. A key difference however, lies in their contrasting band gap; graphene has a band gap of zero (semi-metal) while h-BN...

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Main Author: Ang, Soon Loong
Other Authors: Teo Hang Tong Edwin
Format: Final Year Project (FYP)
Language:English
Published: 2014
Subjects:
Online Access:http://hdl.handle.net/10356/60843
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author Ang, Soon Loong
author2 Teo Hang Tong Edwin
author_facet Teo Hang Tong Edwin
Ang, Soon Loong
author_sort Ang, Soon Loong
collection NTU
description In recent years, two-dimensional (2D) materials like Graphene and Hexagonal Boron Nitride (h-BN) have been generating considerable interest due to their many outstanding properties. A key difference however, lies in their contrasting band gap; graphene has a band gap of zero (semi-metal) while h-BN has a wide band gap of ~6eV (insulator). A ternary material, Boron-Carbon-Nitride (BCN), presents an excellent solution for its ability to tune its band gap. In this report, five BCN hybrid thin films were synthesized using Chemical Vapor Deposition (CVD) method, with ammonia borane (NH3-BH3) as precursor and methane (CH4) as feedstock for carbon. To investigate its band gap, CVD parameters such as dosage of NH3-BH3 (5 to 50 mg) and temperature of heating the precursor (60 to 120oC) were analyzed. Characterization devices like Scanning Electron Microscopy (SEM), Raman Spectroscopy and Ultraviolet-Visible (UV Vis) Spectroscopy provided verification and analysis. Using Tauc's formulation, results showed that the band gaps of BCN samples were successfully lowered from 6 eV to 4.66 eV when the dosage and/or temperature of heating NH3-BH3 were decreased. While band gap engineering was achieved by the author, there exists a threshold limit. Reduction of precursor dosage or temperature beyond this yielded no significant change. Due to the segregating nature of carbon and Boron Nitride (BN) domains, there exist two band gap values in a single BCN hybrid instead of one. This makes application in switching devices an obstacle. For BCN hybrids to achieve band gap engineering and be applied in electronic switching devices, the formation of a true alloy phase is needed.
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spelling ntu-10356/608432023-07-07T16:04:53Z Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD) Ang, Soon Loong Teo Hang Tong Edwin School of Electrical and Electronic Engineering DRNTU::Engineering::Electrical and electronic engineering::Nanoelectronics In recent years, two-dimensional (2D) materials like Graphene and Hexagonal Boron Nitride (h-BN) have been generating considerable interest due to their many outstanding properties. A key difference however, lies in their contrasting band gap; graphene has a band gap of zero (semi-metal) while h-BN has a wide band gap of ~6eV (insulator). A ternary material, Boron-Carbon-Nitride (BCN), presents an excellent solution for its ability to tune its band gap. In this report, five BCN hybrid thin films were synthesized using Chemical Vapor Deposition (CVD) method, with ammonia borane (NH3-BH3) as precursor and methane (CH4) as feedstock for carbon. To investigate its band gap, CVD parameters such as dosage of NH3-BH3 (5 to 50 mg) and temperature of heating the precursor (60 to 120oC) were analyzed. Characterization devices like Scanning Electron Microscopy (SEM), Raman Spectroscopy and Ultraviolet-Visible (UV Vis) Spectroscopy provided verification and analysis. Using Tauc's formulation, results showed that the band gaps of BCN samples were successfully lowered from 6 eV to 4.66 eV when the dosage and/or temperature of heating NH3-BH3 were decreased. While band gap engineering was achieved by the author, there exists a threshold limit. Reduction of precursor dosage or temperature beyond this yielded no significant change. Due to the segregating nature of carbon and Boron Nitride (BN) domains, there exist two band gap values in a single BCN hybrid instead of one. This makes application in switching devices an obstacle. For BCN hybrids to achieve band gap engineering and be applied in electronic switching devices, the formation of a true alloy phase is needed. Bachelor of Engineering 2014-06-02T03:05:57Z 2014-06-02T03:05:57Z 2014 2014 Final Year Project (FYP) http://hdl.handle.net/10356/60843 en Nanyang Technological University 74 p. application/pdf
spellingShingle DRNTU::Engineering::Electrical and electronic engineering::Nanoelectronics
Ang, Soon Loong
Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)
title Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)
title_full Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)
title_fullStr Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)
title_full_unstemmed Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)
title_short Synthesis and characterization of two-dimensional (2D) boron-carbon-nitrogen (BCN) hybrids by chemical vapor deposition (CVD)
title_sort synthesis and characterization of two dimensional 2d boron carbon nitrogen bcn hybrids by chemical vapor deposition cvd
topic DRNTU::Engineering::Electrical and electronic engineering::Nanoelectronics
url http://hdl.handle.net/10356/60843
work_keys_str_mv AT angsoonloong synthesisandcharacterizationoftwodimensional2dboroncarbonnitrogenbcnhybridsbychemicalvapordepositioncvd