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Articles 211 - 240 of 244

Full-Text Articles in Materials Science and Engineering

Solar Selective Optical Coating Made With Metal Nanopaticles For Photovoltaic Thermal Applications, Xin Wang Jan 2009

Solar Selective Optical Coating Made With Metal Nanopaticles For Photovoltaic Thermal Applications, Xin Wang

Material Science and Engineering Theses - Archive

The goal of this research is to fabricate solar selective reflector with suitable optical properties and high thermal and chemical stability for using in the photovoltaic thermal window. While the reflector allows some transmittance in visible spectrum, the mid/far infrared light needs to be reflected back into the window minimizing the IR radiation loss. Nickel/alumina composite was proposed as the solar selective reflector. This thesis consists of two parts - one part concerning the fabrication and characterization of solar selective reflector and another dealing with an optical modeling to simulate the optical properties of the solar selective reflector. The alumina …

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Morphology And Cathode Optimization For Efficient Polymer Bulk Heterojunction Solar Cells, Yi Yang Jan 2009

Morphology And Cathode Optimization For Efficient Polymer Bulk Heterojunction Solar Cells, Yi Yang

Material Science and Engineering Theses - Archive

Efficiency of polymer bulk heterojunction solar cell is highly dependent on the active layer morphology and can be controlled by specific experimental conditions. In this work, the influences of P3HT:PCBM blend composition, solution concentration, and the thermal annealing on the cell performance are presented. The maximum of Jsc and FF are reached when the weight percentage of PCBM in the blend is 60 % under which both high density of donor and accepter interfaces expecting the formation of efficient percolated electron transport paths. 36 mg/ml is found to be the optimum solution concentration for P3HT:PCBM blend and it can be …

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Effect Of Aging On The Transformation Of Phases In Solder Joint Of Pbga Packaging, Jeong-Min Kim Jan 2009

Effect Of Aging On The Transformation Of Phases In Solder Joint Of Pbga Packaging, Jeong-Min Kim

Material Science and Engineering Theses - Archive

This study investigates the microstructural characteristics of 3.0Ag-0.5Cu-Sn (SAC305) solder joint as in assembled state, and their evolution with aging treatment at 100 and 150°C for various hours. Specific aim of the study is 1) to understand thermodynamic stability of as-reflowed microstructure (β-Sn dendrite, inner dendrite Cu6Sn5 intermetallic (IMC) compound, and the eutectic structure), 2) to find direction of their change with aging, and 3) to relate interfacial reaction to such evolution in microstructures. This investigation is spurred by the findings made in a separate study where fatigue resistance of solder joint and failure location shows markedly keen dependence on …

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Structural, Magnetic And Surface Properties Of Rf Magnetron Sputtered Undoped Lanthanum Mangnite Thin Films, Varad Rajan Sakhalkar Jan 2009

Structural, Magnetic And Surface Properties Of Rf Magnetron Sputtered Undoped Lanthanum Mangnite Thin Films, Varad Rajan Sakhalkar

Material Science and Engineering Theses - Archive

In the present study, polycrystalline and epitaxial undoped Lanthanum Manganite (LMO) thin films were deposited by using RF magnetron sputtering on three substrates, Si (100), MgO (100) and LaAlO₃ (100) to study the influence of the misfit strain at the substrate/film interface. The effect of processing conditions on the synthesis of LMO films was studied by conducting deposition on Si wafer. Films were characterized by X-Ray Diffraction (XRD), Atomic Force Microscope (AFM), Energy Dispersive Spectroscopy (EDS) and Superconducting Quantum Interference Device (SQUID) to investigate the influence of processing parameters on their structure and properties. Based on the initial study on …

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Room-Temperature Single-Electron Devices Based On Cmos Fabrication Technology, Vishva Priyo Ray Dec 2008

Room-Temperature Single-Electron Devices Based On Cmos Fabrication Technology, Vishva Priyo Ray

Material Science and Engineering Dissertations - Archive

Single-electron devices, in which the transport and storage of individual electrons is precisely controlled, have many potential benefits in the field of electronics, optics, and sensors. Fabrication of these devices requires the arrangement of device components (Coulomb island, source, drain, and gate electrodes) with nanometer scale precision. Although several methods have successfully demonstrated single-electron behavior, large-scale fabrication of single-electron devices has not been possible.This research aims to - * Come up with a method which would allow the fabrication of single-electron devices on a large scale,* Make the fabrication method compatible with current CMOS technology, and,* Enable room-temperature operation of …

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Design And Fabrication Of Piezoelectric Micro Generator Using Laser Micromachining And Mems Technique, Hyunuk Kim Aug 2008

Design And Fabrication Of Piezoelectric Micro Generator Using Laser Micromachining And Mems Technique, Hyunuk Kim

Material Science and Engineering Theses - Archive

An energy harvesting device based on PbPb(Zr0.52Ti0.48)O3-Pb(Zn1/3Nb2/3)O3 ceramics was fabricated by using laser micromachining technique. It was found that the laser machining process did not have a significant effect on electrical properties of piezoelectric material. The device was found to generate continuous power of 1.13 μW at. 870Hz across a 288.5 kΩ load with power density of 301.3 μW/cm3. The characterization was conducted in low frequency regime of 50-1000Hz at the constant force of 8g(where g=9.8m/s2) In order to fabricate a lead free MEMS device, BaTiO3 was selected as the piezoelectric material. BaTiO3 gel was synthesized by aqueous process using …

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Tribological And Antiwear Mechanisms Of Fluorinated Zinc Dialkyl Dithiophosphate In Comparison To Zinc Dialkyl Dithiophosphate In Engine Oils, Ramoun Mourhatch May 2008

Tribological And Antiwear Mechanisms Of Fluorinated Zinc Dialkyl Dithiophosphate In Comparison To Zinc Dialkyl Dithiophosphate In Engine Oils, Ramoun Mourhatch

Material Science and Engineering Dissertations - Archive

Tribofilms generated in wear tests using lubricants containing fluorinated ZDDP and ZDDP were studied. Fluorinated ZDDP demonstrated superior wear performance compared to ZDDP under tribological conditions even at lower phosphorus levels. Chemical properties and the molecular structure of the fluorinated ZDDP were examined and presented in a previous companion study by Parekh and Aswath [1] using techniques such as NMR and DSC while this study examines the tribological behavior of this compound and the characteristics of the tribofilms formed by it. Ball on cylinder tribological tests were conducted with lubricants containing this new fluorinated thiophosphate compound and compared to lubricants …

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A Study Of The Antiwear Behavior And Oxidation Stability Of Fluorinated Zinc Dialkyl Dithio Phosphate In The Presence Of Antioxidants, Anuradha Somayaji May 2008

A Study Of The Antiwear Behavior And Oxidation Stability Of Fluorinated Zinc Dialkyl Dithio Phosphate In The Presence Of Antioxidants, Anuradha Somayaji

Material Science and Engineering Dissertations - Archive

The antiwear additive Zinc dialkyl dithio phosphate (ZDDP) is one of the most important components of engine-oil additives and a major source of phosphorus. Phosphorus plays a crucial part in mitigating engine wear, yet has been proven harmful to modern catalytic converters. Progressive regulatory caps on phosphorus content in automotive lubricants have led to widespread efforts to reduce its levels. A new fluorinated ZDDP (F-ZDDP) complex developed at the University of Texas at Arlington has found to breakdown at lower temperatures compared to ZDDP and has showed better wear performance than ZDDP alone. This would allow the possibility of further …

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Composition - Microstructure - Property Relationships In Dual Phase Bulk Magnetoelectric Composite, Rashed Adnan Islam May 2008

Composition - Microstructure - Property Relationships In Dual Phase Bulk Magnetoelectric Composite, Rashed Adnan Islam

Material Science and Engineering Dissertations - Archive

The coexistence of coupled electrical and magnetic properties in the “magnetoelectric” material has led to the possibility of developing smarter and smaller electronic components. In order to make this possibility a reality, significant efforts are required to understand the science of magnetoelectric (ME) behavior and apply this understanding to develop higher sensitivity material. The primary aims of this thesis are to identify the role of composition, microstructural variables, composite geometry, texturing, post sintering heat treatment, and nanoscale assembly on ME coefficient. The overall objective is to synthesize, characterize and utilize a high ME coefficient composite. The desired range of ME …

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Fabrication Of Fept Ferromagnetic Nanoparticles, Kevin Eugene Elkins Apr 2008

Fabrication Of Fept Ferromagnetic Nanoparticles, Kevin Eugene Elkins

Material Science and Engineering Dissertations - Archive

Fabrication of chemically disordered FePt particles ranging from 2 - 9 nm with a precision of 1 nm has been achieved through modification of key process variables including surfactant concentration, heating rates and the type of iron precursor. In addition, the shape evolution of the FePt nanoparticles during particle growth can be manipulated to give cubic or rod geometries through changes to the surfactant injection sequence and solvent system. The primary method for synthesis of the disordered FePt nanoparticles is the polyol reduction reported by Fievet et al., which has been modified and used extensively for synthesis of diff ering …

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Corrosion Behavior Of Zn-Ni Coatings Deposited By Electrolytic Plasma Processing, Giancarlo Rios Jan 2008

Corrosion Behavior Of Zn-Ni Coatings Deposited By Electrolytic Plasma Processing, Giancarlo Rios

Material Science and Engineering Theses - Archive

In the current research project, three groups of Zn-Ni coatings of various Ni contents were deposited on comercial carbon steel by electrolytic plasma processing (EPP), a novel surface modification technique. The coating characteristics were studied along with their corrosion behavior in order to determine their potential as electroplated Cd coating replacements. The latter electroplated coatings are currently used in aerospace applications but are toxic and hazardous to humans and the environment. Coating surfaces and cross sections were analyzed by scanning electron microscopy (SEM) while compositional analysis was conducted by energy-dispersive spectroscopy (EDS). Phase structure analysis was carried out by x-ray …

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Fabrication And Characterization Of Cobalt-Diamond-Like-Carbon (Co-Dlc) Nanocomposites, Gunjan Shebe Jan 2008

Fabrication And Characterization Of Cobalt-Diamond-Like-Carbon (Co-Dlc) Nanocomposites, Gunjan Shebe

Material Science and Engineering Theses - Archive

In recent years, synthesis of magnetic nanocomposites has been receiving significant attention. These nanocomposites offer opportunities to develop active nanomaterials with various applications like magnetic data storage and biomedical applications. They can be designed to provide excellent magnetic properties. However, high saturation magnetization materials, such as Co are not biocompatible. Thus, designing nanocomposites with magnetic phase embedded in biocompatible protective shells is of immense interest. In this study, Co-DLC nanocomposites were synthesized using a hybrid CVD/PVD technique and different combination of processing parameters were used to vary the concentration of Co in the nanocomposites. X-ray photoelectron spectroscopy showed, that with …

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Fabrication And Characeterization Of Granular Magnetic Gold Nanoparticles, Rishi Wadhwa Jan 2008

Fabrication And Characeterization Of Granular Magnetic Gold Nanoparticles, Rishi Wadhwa

Material Science and Engineering Theses - Archive

In recent years, gold and magnetic nanoparticles have showed great potential in biomedical applications. Magnetic nanoparticles can be used in both in- vivo and in-vitro applications such as drug and gene delivery, hyperthermia treatment of cancer, MRI contrast enhancement, cell labeling and magnetic separation. Due to the surface plasmon resonance effect (SPR), gold nanoparticles strongly absorb and scatter visible and infrared light in resonance with SPR. They have been exploited for bioimaging and photothermal therapy applications. This is why different sizes and shapes of Au nanoparticles exhibit different colors.In this thesis, we are investigating a new type of nanoparticles, granular …

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Synthesis, Structure And Characterization Of Silver Doped Diamond Like Carbon Thin Films, Pankaj Jyoti Hazarika Dec 2007

Synthesis, Structure And Characterization Of Silver Doped Diamond Like Carbon Thin Films, Pankaj Jyoti Hazarika

Material Science and Engineering Theses - Archive

Diamond like carbon (DLC) films have gained grounds in the biomedical field as an inert, biocompatible, low friction and wear resistant coating and are widely used in heart valves, coronary artery stents, dental implants, knee prosthesis and other vascular devices. In addition, Ag nanoparticles/films can prevent the formation of biofilm on biomedical implants by degrading the metabolic activities like permeability and respiration and also impair DNA replicability. Thus, Ag-doped DLC (Ag-DLC) can serve as a multifunctional bio coating combining desirable antibacterial and physical/ mechanical characteristics. In the present study, Ag-DLC films were synthesized utilizing a hybrid Plasma CVD and Magnetron …

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Synthesis And Characterization Of Ferromagnetic Nanoparticles, Kazuaki Yano Dec 2007

Synthesis And Characterization Of Ferromagnetic Nanoparticles, Kazuaki Yano

Material Science and Engineering Theses - Archive

Ferromagnetic nanoparticles and their bimagnetic nanoparticles with uniform size distribution have drawn great attention in the past decades because of their unique magnetic properties and potential applications in high density recording media, exchange-spring permanent magnets and biotechnology. In this thesis, synthesis and characterization of ferromagnetic nanoparticles (FePt, Sm-Co system) and bimagnetic nanoparticles (FePt/Fe3O4, FePt/Au) are reported. FePt nanoparticles with different sizes and compositions were successfully synthesized via chemical synthesis. FePt particle size was tuned to a range of from 3 nm to 8 nm with 1 nm accuracy by changing the surfactant to Pt precursor ratio. By optimizing the amount …

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Surface Patterning Of Biodegradable Polymer In Tissue Engineering By Applying Photolithography, Lee-Chun Su Dec 2007

Surface Patterning Of Biodegradable Polymer In Tissue Engineering By Applying Photolithography, Lee-Chun Su

Material Science and Engineering Theses - Archive

The prevalence of cardiovascular disease and inherent problems with current surgical therapies has prompted major efforts in the field of vascular tissue engineering. While there have been significant advances towards creating functional blood vessel substitutes, the fabrication of a vascular graft with mechanical, structural and functional properties similar to native vessels has not yet been achieved. We have presented an observation of a new biodegradable polymer utilized on the research of tissue engineering. Our idea was to create a structure to imitate blood vessel muscles in vitro and also to guide the cells when they start spreading and trying to …

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Thermally Activated Sulfurization Scheme For Cuins2 Solar Cells, Karan Agrawal Dec 2007

Thermally Activated Sulfurization Scheme For Cuins2 Solar Cells, Karan Agrawal

Material Science and Engineering Theses - Archive

Chalcopyrite Solar Cells are now being fabricated on flexible (polymer) substrates. However, CuInS2 solar cells have not been fabricated on the polymer substrates on the commercial scale due the sulfurization temperature which limits the use of polymer substrates during fabrication. To overcome this problem a thermally activated sulfurization process for the manufacture of CuInS2 solar cells from the Cu-In bilayers is described in this work. This sulfurization process can be employed for lower temperature for the formation of the absorber layer. For the sulfurization, the Cu-In bilayer with different compositions is prepared by thermal evaporation in which the In-rich film …

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Diffusion-Free Back Contact Solar Cells On S-Passivated Si(100) Substrates, Guanghua Song Dec 2007

Diffusion-Free Back Contact Solar Cells On S-Passivated Si(100) Substrates, Guanghua Song

Material Science and Engineering Dissertations - Archive

A diffusion-free back contact solar cell is proposed in this work. The textured front-side of this cell is coated with ~100 nm thermal SiO2 to enhance the light trapping meanwhile reduce the surface recombination velocity (SRV). The back-side of this cell is finger-patterned, using a diffusion-free junction as its emitter region and Al-Si alloy as its base contact. The diffusion-free junction is made by a Schottky contact between low work-function metal aluminum (Al) and sulfur (S)-passivated p-type Si(100) surface. Solution-based S passivation is one of the experimental realizations of the "valence-mending concept". Previously developed MBE (molecular bean epitaxy) selenium (Se) …

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Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager Aug 2007

Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager

Material Science and Engineering Theses - Archive

Several undisclosed fiberglass and carbon fiber laminates with toughened resin systems were tested and examined. Experiments were conducted to determine Modes I and II interlaminar fracture toughness for each of the nine laminates with varying types of processing forms such as roving, tape, and slit tape of glass and carbon fibers. Fractography was then used to correlate the fracture toughness results with the unique characteristics and failure mechanisms. Overall, fiberglass laminates had larger interlaminar fracture toughness for both Modes I and II over the carbon laminates. This was also confirmed by the significant amount of the fractured surface area and …

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Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure Aug 2007

Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure

Material Science and Engineering Theses - Archive

In the field of organic solar cell, the conjugated polymer-fullerene bulk heterojunction concept is one of the ongoing research interests. In this work, the use of de-oxyribose nucleic acid/ hexadecyl trimethyl ammonium chloride (DNA/CTMA) thin films as hole transport layer in poly(3-hexylthiophene)-methanofullerene (P3HT-PCBM) bulk heterojunction polymer solar cell is demonstrated. P3HT-PCBM bulk heterojunction polymer solar cell was fabricated with a DNA complex layer replacing commonly used PEDOT-PSS (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS). While PEDOT-PSS, as a hole transport and electron blocking layer, often improves the solar cell performance by improving fill factor, it requires careful engineering of spin-coating for the aqueous solution of …

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Synthesis And Characterization Of Polythiophene Derivatives, Xin Chen May 2007

Synthesis And Characterization Of Polythiophene Derivatives, Xin Chen

Material Science and Engineering Dissertations - Archive

In Chapter 1, the history of conducting polymers, especially polythiophene and its derivatives, was briefly reviewed. Different approaches of structural modifications to afford small bandgap polythiophene derivatives were discussed. The emergence of metal-containing polymers (metallopolymers) as functional materials has attracted tremendous attention around the world. Introducing metals into thiophene-based oligomers and polymers, whether the backbone or the side chain of the p-conjugated framework, the electronic, optical, or magnetic properties of the material are expected to by significantly affected by metals through various mechanisms. Synthesis methods to prepare poly(thienylene vinylene) were also briefly reviewed in this chapter. In Chapter 2, the …

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Experimental Study Of Laminated Composite Tubes Under Bending, Puneet Saggar May 2007

Experimental Study Of Laminated Composite Tubes Under Bending, Puneet Saggar

Material Science and Engineering Theses - Archive

Bending stiffness of laminated composite tubes was determined experimentally using four-point bending test. The experimental results were compared with the results obtained by the laminated plate and smear property approaches. The results indicate that experimental values are closer to prediction of the laminated plate approach compared to smear property approach. Effects of tube radius and stacking sequence and fiber orientation of the walled thickness laminate on bending stiffness and strength of composite tubes were studied. Fracture analysis was conducted to investigate the failure process of the tube. Both techniques of x-ray radiography and optical microscopy were used in this study. …

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Surface Modification Of 6h-Sic Under Vacuum Annealing Studied By Time Of Flight Positron Annihilation Induced Auger Electron Spectroscopy, Saurabh Mukherjee Jan 2007

Surface Modification Of 6h-Sic Under Vacuum Annealing Studied By Time Of Flight Positron Annihilation Induced Auger Electron Spectroscopy, Saurabh Mukherjee

Material Science and Engineering Theses - Archive

This thesis presents the first study of vacuum annealing of 6H- SiC surface using Time-of-Flight-Positron Annihilation induced Auger Electron Spectroscopy(TOF-PAES) . The study was the first application of a TOF-PAES spectrometer to the SiC. The increased efficiency of the TOF-PAES allows us to see simultaneously for the first time Si-LVV, C-KVV, O-KVV peaks in the PAES spectrum for SiC. The top layer surface concentrations of C, O and Si were monitored by TOF-PAES surface. The results indicate that the SiC surface was initially covered with a layer containing oxygen but largely devoid of Si which was subsequently removed as a …

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Thermal Failure Mechanism And Voltammetry Metrology For Cu/Barrier/Low K Integration, Dongmei Meng Dec 2006

Thermal Failure Mechanism And Voltammetry Metrology For Cu/Barrier/Low K Integration, Dongmei Meng

Material Science and Engineering Dissertations - Archive

The present study investigates the thermal stability of Cu/barrier/porous low κ (PLK) integration first, and then a new characterization method based on voltammetry is developed to characterize quality of diffusion barrier and pore structure in low κ materials and its thermal stability. The study of thermal stability reveals that Cu/barrier/PLK interconnect fails by Cu out-diffusion through the defects of diffusion barrier into the PLK structure, which is driven by oxidation and stress gradient within the interconnect structure. The failure appears to be triggered by defects in diffusion barrier, however, such defects are not effectively detected by TEM observation due to …

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Preparation And Characterization Of Properties Of Electrodeposited Copper Oxide Films, Longcheng Wang Dec 2006

Preparation And Characterization Of Properties Of Electrodeposited Copper Oxide Films, Longcheng Wang

Material Science and Engineering Dissertations - Archive

Copper oxides, including cuprous oxide and cupric oxide, are prepared by electrochemical deposition. The structural, optical and electrical properties of as-deposited copper oxides are evaluated, based on which cuprous oxide is selected as a promising material for photovoltaic applications. Electrodeposited cuprous oxide is a p-type semiconductor with a direct band gap of 2.06 eV. The mechanism of how pH affects the structural and electrical properties of electro-deposited cuprous oxide films is studied. In the pH range of 7.5 to 12.0, there are three different preferred crystal orientations: (100), (110) and (111). With different orientations, cuprous oxide shows different surface morphology …

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Micromechanical Analysis Of Yielding For Particulate Filled Composites, Chih-Ta Chen Dec 2006

Micromechanical Analysis Of Yielding For Particulate Filled Composites, Chih-Ta Chen

Material Science and Engineering Theses - Archive

Particulate filled composites are hybrid materials which consist of particulates held together by a matrix. In this thesis, a simulation method to obtain overall failure criterion for particulate filled composites based on the computer software "MATHEMATICA" will be presented. The composite is assumed to fail at the matrix just outside the inclusion. By Self-Consistent Method, the composite can be imaged as an inclusion embedded within effective matrix. The Equivalent Inclusion method is then applied to stimulate the stress field within the inclusion. Stress just outside inclusion can be calculated because interfacial traction force on the boundary of inclusion is continuous. …

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Investigation On The Mechanism Of Interface Electromigration (Em) In Copper (Cu) Thin Films, Jee Yong Kim Dec 2006

Investigation On The Mechanism Of Interface Electromigration (Em) In Copper (Cu) Thin Films, Jee Yong Kim

Material Science and Engineering Dissertations - Archive

This study concerns the mechanism of the interface electromigration (EM) in copper (Cu) thin films. While EM in Cu is one of the most concerned reliability failure phenomena in Cu interconnects used microelectronic devices, its mechanism is not well understood yet. In order for better understanding of the EM mechanism, this study attempt to investigate the interface EM mechanism by examining the passivation effects on Cu EM using a cross-strip structure where Cu lines are cross-stripped with different passivation layers. From the observation of the marker polarity (hillocks and voids), the interface EM mechanism is determined whether the passivation layer …

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Synthesis And Characterization Of Multifunctional Oxides For Force And Gas Sensors, Vaneet Sharma Dec 2006

Synthesis And Characterization Of Multifunctional Oxides For Force And Gas Sensors, Vaneet Sharma

Material Science and Engineering Theses - Archive

In this research work, the piezoresistivity phenomena in multifunctional oxides of La0.8Sr0.2MnO3 (LSMO) and composites of LSMO - (Ce0.12Zr0.88)O2 has been investigated for force and gas sensor applications in harsh environments including automobile and aerospace industry. In these applications, there is a need of material with high mechanical strength with multi sensing capabilities. The inherent sensing capabilities allow the material to be implemented at variety of platforms. Previously, LSMO polycrystalline ceramics have been studied as a cathode material in solid oxide fuel cells (SOFC). Owing to its colossal magnetoresistance properties, this material has also been extensively studied for use in …

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Self-Assembly Of Nanoparticles In Photonic Crystal Cavities For Optoelectronic Devices, Geetha Thiruvengadam Aug 2006

Self-Assembly Of Nanoparticles In Photonic Crystal Cavities For Optoelectronic Devices, Geetha Thiruvengadam

Material Science and Engineering Theses - Archive

Photonic crystals (PhC) offer many advantages in optoelectronics field. The focus of this thesis is to investigate a self assembly process for the formation of thin film based one-dimensional PhC and the integration of nanoparticles with two-dimensional PhC. Nanoparticles like SiO2, TiO2, PolyStyrene, and PbSe (with different surface properties) were subjected to different experiments. Various techniques, such as spin coating, immersion technique, evaporation induced assembly technique, have been carried out by varying parameters like time, temperature, position of the substrate, etc.,. An optimized method for the fabrication of 1D PhC was found to be evaporation induced Self-Assembly method by varying …

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Preparation And Characterization Of Doped Zinc Oxide, Yogeeswaran Ganesan Aug 2006

Preparation And Characterization Of Doped Zinc Oxide, Yogeeswaran Ganesan

Material Science and Engineering Theses - Archive

Cathodic electrodeposition was used to prepare thin films of ZnO doped with Cd, from oxygenated KCl electrolyte containing ZnCl2 and CdCl2 in various molar ratios ranging from 0 mM to 5.0 mM each. Evidence for doping was obtained from X-ray powder diffraction, diffuse reflectance, chronopotentiometry, and X-ray photoelectron spectroscopy data. The Cd-doped ZnO samples showed a superior photoresponse relative to undoped ZnO. Cadmium- and indium-doped ZnO were prepared by combustion synthesis using CdCl2 and InCl3 as dopant precursors along with zinc nitrate and urea as the combustion mixture. The doped samples were compared and contrasted with undoped ZnO using scanning …

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