Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition

This study presents the synthesis of Silicon Carbide Quantum Dots (SiC QDs) by Very High Frequency-Plasma Enhanced Chemical Vapour Deposition (VHF-PECVD) method. Si (100) was used as a substrate where the growth was performed at a much lower temperature (100°C) than previous work. Besides, the growt...

Full description

Saved in:

Bibliographic Details
Main Author:	Jusoh, Haezah Munyati
Format:	Thesis
Language:	English
Published:	2020
Subjects:	QC Physics
Online Access:	http://eprints.utm.my/id/eprint/101977/1/HaezahMunyatiJusohMFS2020.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-utm-ep.101977
record_format	uketd_dc
spelling	my-utm-ep.1019772023-07-25T10:04:12Z Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition 2020 Jusoh, Haezah Munyati QC Physics This study presents the synthesis of Silicon Carbide Quantum Dots (SiC QDs) by Very High Frequency-Plasma Enhanced Chemical Vapour Deposition (VHF-PECVD) method. Si (100) was used as a substrate where the growth was performed at a much lower temperature (100°C) than previous work. Besides, the growth time has been shorten in order to enhance the SiC QDs growth process. The effect of different Radio Frequency (RF) plasma frequencies (150 MHz, 160 MHz and 200 MHz) on the structural properties of SiC QDs were investigated. The growth parameters such as growth temperatures, growth time and hydrogen flow rates were manipulated in order to study the optical properties of SiC QDs grown at 150 MHz. Silane (SiH4) and methane (CH4) were used as precursor gases and both were decomposed by RF plasma excitation to silicon (Si) and carbon (C) respectively at certain temperature for the growth of SiC QDs. The samples were then characterized by Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Microscopy (EDX) and Atomic Force Microscopy (AFM) to observe the morphology and structure of quantum dots. FESEM images show that the dots diameter increased as the RF plasma increased from 150 MHz to 200 MHz and the EDX analysis further confirmed that quantum dots consist mostly of silicon (Si), carbon (C) and oxygen (O) elements. From the cross-sectional image, it was suggested that the growth of SiC quantum dots follows Stranski-Krastanow (S-K) mode. Moreover, AFM results revealed that the surface roughness also increased concurrently with the increased of RF plasma frequencies. Raman spectra analysis and X-Ray Diffraction (XRD) pattern further confirmed that some of them composed of crystalline peak of SiC at 780.32 cm-1 with (200) growth plane. For emission properties of SiC QDs, two peaks detected for all samples located at 407 nm and 571 nm which are comparable to the 6H-SiC and 3C-SiC crystal structures. The energy band gap of a sample grown at 160 MHz with growth temperature of 200 °C was 3.19 eV which is approximately the energy band gap of 4H-SiC (3.20 eV). In conclusion, this enhancement method in growing SiC QDs can be applied in future study in terms of its material properties and also its application in nanodevice technology. 2020 Thesis http://eprints.utm.my/id/eprint/101977/ http://eprints.utm.my/id/eprint/101977/1/HaezahMunyatiJusohMFS2020.pdf application/pdf en public http://dms.library.utm.my:8080/vital/access/manager/Repository/vital:146349 masters Universiti Teknologi Malaysia, Faculty of Science Faculty of Science
institution	Universiti Teknologi Malaysia
collection	UTM Institutional Repository
language	English
topic	QC Physics
spellingShingle	QC Physics Jusoh, Haezah Munyati Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
description	This study presents the synthesis of Silicon Carbide Quantum Dots (SiC QDs) by Very High Frequency-Plasma Enhanced Chemical Vapour Deposition (VHF-PECVD) method. Si (100) was used as a substrate where the growth was performed at a much lower temperature (100°C) than previous work. Besides, the growth time has been shorten in order to enhance the SiC QDs growth process. The effect of different Radio Frequency (RF) plasma frequencies (150 MHz, 160 MHz and 200 MHz) on the structural properties of SiC QDs were investigated. The growth parameters such as growth temperatures, growth time and hydrogen flow rates were manipulated in order to study the optical properties of SiC QDs grown at 150 MHz. Silane (SiH4) and methane (CH4) were used as precursor gases and both were decomposed by RF plasma excitation to silicon (Si) and carbon (C) respectively at certain temperature for the growth of SiC QDs. The samples were then characterized by Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Microscopy (EDX) and Atomic Force Microscopy (AFM) to observe the morphology and structure of quantum dots. FESEM images show that the dots diameter increased as the RF plasma increased from 150 MHz to 200 MHz and the EDX analysis further confirmed that quantum dots consist mostly of silicon (Si), carbon (C) and oxygen (O) elements. From the cross-sectional image, it was suggested that the growth of SiC quantum dots follows Stranski-Krastanow (S-K) mode. Moreover, AFM results revealed that the surface roughness also increased concurrently with the increased of RF plasma frequencies. Raman spectra analysis and X-Ray Diffraction (XRD) pattern further confirmed that some of them composed of crystalline peak of SiC at 780.32 cm-1 with (200) growth plane. For emission properties of SiC QDs, two peaks detected for all samples located at 407 nm and 571 nm which are comparable to the 6H-SiC and 3C-SiC crystal structures. The energy band gap of a sample grown at 160 MHz with growth temperature of 200 °C was 3.19 eV which is approximately the energy band gap of 4H-SiC (3.20 eV). In conclusion, this enhancement method in growing SiC QDs can be applied in future study in terms of its material properties and also its application in nanodevice technology.
format	Thesis
qualification_level	Master's degree
author	Jusoh, Haezah Munyati
author_facet	Jusoh, Haezah Munyati
author_sort	Jusoh, Haezah Munyati
title	Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
title_short	Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
title_full	Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
title_fullStr	Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
title_full_unstemmed	Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
title_sort	structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition
granting_institution	Universiti Teknologi Malaysia, Faculty of Science
granting_department	Faculty of Science
publishDate	2020
url	http://eprints.utm.my/id/eprint/101977/1/HaezahMunyatiJusohMFS2020.pdf
_version_	1776100817088020480

Structural and optical properties of silicon carbide quantum dots grown by very high frequency plasma enhanced chemical vapour deposition

Similar Items