Search Results

open access

Microstructural Studies of Dental Amalgams Using Analytical Transmission Electron Microscopy

Description: Dental amalgams have been used for centuries as major restorative materials for decaying teeth. Amalgams are prepared by mixing alloy particles which contain Ag, Sn, and Cu as the major constituent elements with liquid Hg. The study of microstructure is essential in understanding the setting reactions and improving the properties of amalgams. Until the work reported in this dissertation, optical microscopy (OM), scanning electron microscopy (SEM), and x-ray diffractometry (XRD) were used common… more
Date: May 1997
Creator: Hooghan, Tejpal Kaur
Partner: UNT Libraries
open access

A Novel Process for GeSi Thin Film Synthesis

Description: A unique process of fabricating a strained layer GexSi1-x on insulator is demonstrated. Such strained heterostructures are useful in the fabrication of high-mobility transistors. This technique incorporates well-established silicon processing technology e.g., ion implantation and thermal oxidation. A dilute GeSi layer is initially formed by implanting Ge+ into a silicon-on-insulator (SOI) substrate. Thermal oxidation segregates the Ge at the growing oxide interface to form a distinct GexSi1-x … more
Date: December 2007
Creator: Hossain, Khalid
Partner: UNT Libraries
open access

Ion Beam Synthesis of Binary and Ternary Transition Metal Silicide Thin Films

Description: Among the well-known methods to form or modify the composition and physical properties of thin films, ion implantation has shown to be a very powerful technique. In particular, ion beam syntheses of binary iron silicide have been studied by several groups. Further, the interests in transition metal silicide systems are triggered by their potential use in advanced silicon based opto-electronic devices. In addition, ternary silicides have been by far less studied than their binary counterparts de… more
Date: December 2016
Creator: Lakshantha, Wickramaarachchige Jayampath
Partner: UNT Libraries
open access

Nanoscale Materials Applications: Thermoelectrical, Biological, and Optical Applications with Nanomanipulation Technology

Description: In a sub-wavelength scale, even approaching to the atomic scale, nanoscale physics shows various novel phenomena. Since it has been named, nanoscience and nanotechnology has been employed to explore and exploit this small scale world. For example, with various functionalized features, nanowire (NW) has been making its leading position in the researches of physics, chemistry, biology, and engineering as a miniaturized building block. Its individual characteristic shows superior and unique featur… more
Date: August 2011
Creator: Lee, Kyung-Min
Partner: UNT Libraries
open access

Synthesis and Characterization of Ion Beam Assisted Silver Nanosystems in Silicon Based Materials for Enhanced Photocurrent Collection Efficiency

Description: In recent years a great deal of interest has been focused on the synthesis of transitional metal (e.g. Ag, Cu, Fe, Au) nanosystems at the surface to sub-surface regions of Si and SiO2 matrices for fundamental understanding of their structures as well as for development of technological applications with enhanced electronic and optical properties. The applications of the metal nanoparticle or nanocluster (NC) systems range from plasmonics, photovoltaic devices, medical, and biosensors. In all o… more
Date: May 2015
Creator: Dhoubhadel, Mangal S.
Partner: UNT Libraries
open access

Synthesis, Characterization, Structural, and Optical Properties of Zinc Oxide Nanostructures Embedded in Silicon Based Substrates

Description: Structural and optical properties of ZnO nanostructures synthesized by low energy ion implantation technique were examined. ZnO molecular ions were implanted into Si/SiO2 substrates at room temperature and then furnace annealed under different temperatures and environments. In all as-implanted samples only Zn nanostructures with varying diameters distributed into the Si/SiO2 matrices were observed. No trace of ZnO was found. The distributions of Zn nanostructures in Si/SiO2 closely matched resu… more
Date: May 2014
Creator: Pandey, Bimal
Partner: UNT Libraries

Fabrication of Nano-Channel Templates and a Study of the Electrical and Magnetic Properties of Nanowires Grown in Template Pores

Description: This thesis is a study of the structural, electrical and magnetic properties of indium antimonide (InSb) nanowires (NWs), that were synthesized by a template-assisted ordered growth technique via electrochemical deposition. InSb was chosen for this study because of its intrinsic properties that make it a material of choice for applications in high channel mobility, infrared (IR) sensing, thermoelectrics, and magnetoresistive sensing martials. This work has four main components: (i) Growth in co… more
Date: May 2020
Creator: Singh, Abhay Pratap
Partner: UNT Libraries
open access

A New Approach for Transition Metal Free Magnetic Sic: Defect Induced Magnetism After Self-ion Implantation

Description: SiC has become an attractive wide bandgap semiconductor due to its unique physical and electronic properties and is widely used in high temperature, high frequency, high power and radiation resistant applications. SiC has been used as an alternative to Si in harsh environments such as in the oil industry, nuclear power systems, aeronautical, and space applications. SiC is also known for its polytypism and among them 3C-SiC, 4H-SiC and 6H-SiC are the most common polytypes used for research purpo… more
Date: May 2013
Creator: Kummari, Venkata Chandra Sekhar
Partner: UNT Libraries

Low-Energy Electron Irradiation of 2D Graphene and Stability Investigations of 2D MoS2

Description: In this work, we demonstrate the mechanism for etching exfoliated graphene on SiO2 and other technological important substrates (Si, SiC and ITO), using low-energy electron sources. Our mechanism is based on helium ion sputtering and vacancy formation. Helium ions instead of incident electrons cause the defects that oxygen reacts with and etches graphene. We found that etching does not occur on low-resistivity Si and ITO. Etching occurs on higher resistivity Si and SiC, although much less than … more
Date: August 2021
Creator: Femi Oyetoro, John Dideoluwa
Partner: UNT Libraries
Back to Top of Screen