Fabrication and characterization of one-dimensional solid-state model systems...François Bianco
This document summarizes research on fabricating and characterizing one-dimensional nanoline structures on silicon. It describes how bismuth nanolines were self-assembled through deposition on a silicon surface, forming constant-width chains over micrometer lengths. After removing the bismuth, the silicon surface formed a template of "Haiku stripes" consisting of hydrogen-terminated silicon dimers. Alternating patterns of these dimers were also created through voltage control. The document outlines additional methods to synthesize nanoline structures like "Haiku dangling bond rows" and characterizes their properties through microscopy and spectroscopy. The goal is to use these one-dimensional templates to assemble and study molecular and atomic chains with potential applications in nanotechnology.
This document summarizes research on controlling the morphology of electrodeposited copper thiocyanate (CuSCN) films by varying the applied bias voltage. SEM images show that well-shaped nanorods are deposited at -0.3V, and increasing the voltage causes the nanorods to agglomerate gradually. TEM confirms the nanorod structure. Deposition time also increases nanorod diameter. The CuSCN films were applied in semiconductor sensitized solar cells, achieving a power conversion efficiency of 3.9%.
This document describes the key process steps in a standard CMOS fabrication process flow. It begins with an overview of basic CMOS circuits and substrate preparation. Then each major step is outlined, including well formation through ion implantation, gate oxide growth, polysilicon deposition and patterning, source/drain implantation and annealing. Additional metal layers are deposited and patterned before passivation completes the CMOS structure. The process requires 16 photomasks and over 100 individual process steps to fabricate modern integrated circuits using complementary NMOS and PMOS transistors.
The document discusses different methods of well formation in CMOS devices, including N well formation, P well formation, and twin tub formation. Twin tub formation allows for separate optimization of N-type and P-type transistors by providing independent control over threshold voltage, body effect, and gain for each transistor type. The twin tub formation process involves starting with a lightly doped substrate and forming an epitaxial layer to prevent latch up. P-wells and N-wells are then formed through a process using photoresist masks, boron and phosphorus implants, and oxide layers.
Pulsed laser deposition is a thin film growth technique where a high-power pulsed laser is focused on a target in a vacuum chamber, vaporizing the target material which then condenses on a substrate. It allows for the growth of a wide variety of oxide, nitride, metal and other films. The composition of the deposited film mimics that of the target. PLD systems are relatively inexpensive and easy to use, leading to its popularity in academic research. Key advantages include nearly stoichiometric transfer, flexibility in depositing different materials, and real-time thickness control. The laser-target interaction process involves rapid heating, vaporization and formation of an energetic plume that interacts strongly with the substrate during deposition.
Minority carrier lifetime in solar cellsajay singh
This document summarizes a student's summer training presentation on improving the efficiency of solar cells. It discusses texturing silicon wafers using various methods like laser texturization and reactive ion etching to reduce reflection losses. It also describes experiments with anisotropic wet etching using KOH solutions and additives to texture wafers, as well as different chemical polishing techniques using HF and HNO3 solutions at various temperatures and times to round pyramid structures and increase minority carrier lifetime and cell efficiency. The results showed that chemical polishing a textured wafer for 5 minutes with a diluted HF/HNO3 solution at 5°C reduced reflection to 12.2% and increased minority carrier lifetime to 65.6 microseconds.
El documento define la discriminación racial y explica sus orígenes históricos, incluyendo el racismo en Europa, Estados Unidos y el movimiento nazi. También discute grupos como el Ku Klux Klan y líderes contra el racismo como Martin Luther King Jr. Finalmente, analiza aspectos éticos y sociales del racismo como la generación de miedo y odio entre las personas.
Fabrication and characterization of one-dimensional solid-state model systems...François Bianco
This document summarizes research on fabricating and characterizing one-dimensional nanoline structures on silicon. It describes how bismuth nanolines were self-assembled through deposition on a silicon surface, forming constant-width chains over micrometer lengths. After removing the bismuth, the silicon surface formed a template of "Haiku stripes" consisting of hydrogen-terminated silicon dimers. Alternating patterns of these dimers were also created through voltage control. The document outlines additional methods to synthesize nanoline structures like "Haiku dangling bond rows" and characterizes their properties through microscopy and spectroscopy. The goal is to use these one-dimensional templates to assemble and study molecular and atomic chains with potential applications in nanotechnology.
This document summarizes research on controlling the morphology of electrodeposited copper thiocyanate (CuSCN) films by varying the applied bias voltage. SEM images show that well-shaped nanorods are deposited at -0.3V, and increasing the voltage causes the nanorods to agglomerate gradually. TEM confirms the nanorod structure. Deposition time also increases nanorod diameter. The CuSCN films were applied in semiconductor sensitized solar cells, achieving a power conversion efficiency of 3.9%.
This document describes the key process steps in a standard CMOS fabrication process flow. It begins with an overview of basic CMOS circuits and substrate preparation. Then each major step is outlined, including well formation through ion implantation, gate oxide growth, polysilicon deposition and patterning, source/drain implantation and annealing. Additional metal layers are deposited and patterned before passivation completes the CMOS structure. The process requires 16 photomasks and over 100 individual process steps to fabricate modern integrated circuits using complementary NMOS and PMOS transistors.
The document discusses different methods of well formation in CMOS devices, including N well formation, P well formation, and twin tub formation. Twin tub formation allows for separate optimization of N-type and P-type transistors by providing independent control over threshold voltage, body effect, and gain for each transistor type. The twin tub formation process involves starting with a lightly doped substrate and forming an epitaxial layer to prevent latch up. P-wells and N-wells are then formed through a process using photoresist masks, boron and phosphorus implants, and oxide layers.
Pulsed laser deposition is a thin film growth technique where a high-power pulsed laser is focused on a target in a vacuum chamber, vaporizing the target material which then condenses on a substrate. It allows for the growth of a wide variety of oxide, nitride, metal and other films. The composition of the deposited film mimics that of the target. PLD systems are relatively inexpensive and easy to use, leading to its popularity in academic research. Key advantages include nearly stoichiometric transfer, flexibility in depositing different materials, and real-time thickness control. The laser-target interaction process involves rapid heating, vaporization and formation of an energetic plume that interacts strongly with the substrate during deposition.
Minority carrier lifetime in solar cellsajay singh
This document summarizes a student's summer training presentation on improving the efficiency of solar cells. It discusses texturing silicon wafers using various methods like laser texturization and reactive ion etching to reduce reflection losses. It also describes experiments with anisotropic wet etching using KOH solutions and additives to texture wafers, as well as different chemical polishing techniques using HF and HNO3 solutions at various temperatures and times to round pyramid structures and increase minority carrier lifetime and cell efficiency. The results showed that chemical polishing a textured wafer for 5 minutes with a diluted HF/HNO3 solution at 5°C reduced reflection to 12.2% and increased minority carrier lifetime to 65.6 microseconds.
El documento define la discriminación racial y explica sus orígenes históricos, incluyendo el racismo en Europa, Estados Unidos y el movimiento nazi. También discute grupos como el Ku Klux Klan y líderes contra el racismo como Martin Luther King Jr. Finalmente, analiza aspectos éticos y sociales del racismo como la generación de miedo y odio entre las personas.
El documento describe los significados y asociaciones de los colores rojo, naranja y amarillo. El rojo es un color caliente que evoca emociones como el amor y la guerra. El naranja combina la energía del rojo con la alegría del amarillo. El amarillo simboliza la luz del sol y representa la felicidad y la energía. Cada color tiene diferentes asociaciones culturales y psicológicas.
Este documento describe estrategias para buscar y seleccionar información en entornos visuales como Internet. Explica la diferencia entre buscadores y metabuscadores, y da ejemplos de cada uno. También presenta el modelo Gavilán de cuatro pasos para guiar a estudiantes en la búsqueda de información, y define la competencia para manejar información.
Dokumen ini berisi iklan layanan jual beli spring bed dari toko springbedsurabaya.com yang berlokasi di Jalan Dukuh Kupang 25 no 37 Surabaya dengan nomor telepon 031-5617601. Toko ini menawarkan berbagai macam spring bed dengan harga terbaru dan menyarankan untuk memeriksa katalog harga lebih lanjut di website www.springbedsurabaya.com.
A mãe fez biscoitos para Lena e Beto. Muitas crianças vizinhas foram chegando e comendo os biscoitos. A cada vez que tocavam a campainha, dividiam os biscoitos restantes igualmente entre todos. No final, a vovó apareceu com mais biscoitos para que todos pudessem comer até a saciedade.
El documento presenta el modelo de negociación de Fisher y Ury, también conocido como el modelo de Harvard. Describe los pasos del análisis integral del proceso de negociación según este modelo, incluyendo identificar el problema, analizar sus posibles causas, seleccionar estrategias de solución y establecer planes de acción específicos. También enfatiza la importancia de una visión sistémica que considere la multiplicidad de factores interrelacionados en el proceso de negociación.
"ASP.NET Core est le nouveau framework Open Source et Cross Platform pour développer des applications connectées modernes : applications webs, backends mobiles ou applications IoT.
ASP.NET Core peut tourner sur .NET Core ou sur le .NET Framework complet. Son architecture a été complètement revue depuis la précédente génération du framework afin de fournir une expérience de développement plus moderne, plus flexible et plus performante.
Venez découvrir les bases d'ASP.NET Core afin de pouvoir l'envisager dans vos futurs projets !"
The document discusses the ELF file format and dynamic linking process. It describes the ELF header, program header table, and segments that make up an ELF file. The dynamic linker loads segments into memory, resolves symbols using hash tables, and initializes shared libraries and the main executable in the correct order. Symbol resolution involves determining the symbol hash, searching hash buckets in each library, and comparing names.
A few Curious Aspects of ZnO Nanostructures - Prof.Joy MitraSTS FORUM 2016
This document summarizes research on designing defects in ZnO nanostructures. It discusses how ZnO naturally forms with n-type doping due to oxygen vacancies and zinc interstitials. The researcher investigates controlling the ratio of zinc interstitials to oxygen vacancies to tune the material's optical and electrical properties. Photoluminescence and conductive atomic force microscopy experiments on ZnO nanorods with varying defect concentrations show changes in emission spectra and localized photoresponse correlated with grain structure. The findings provide insight into defect engineering of ZnO for optoelectronic applications.
ZnS Nanostructures: Synthesis, Characterization, and Theory - Defense Present...Daniel Moore
Daniel Moore's Ph.D. defense presentation summarizes his research on synthesizing and characterizing novel ZnS nanostructures. He discusses various ZnS nanostructures including nanobelts, aligned nanowires, nanohelices, and ultralong core-shell ZnS-SiO2 nanowires. Various growth mechanisms are proposed including vapor-liquid-solid and vapor-solid processes. Parameters like temperature, time, and catalyst are found to influence the morphology. Characterization using TEM, XRD and photoluminescence elucidate the crystal structure and composition of the nanostructures.
Synthesis And Characterization Of Individual ZnO NanowiresMartial Duchamp
This document summarizes research on synthesizing and characterizing individual zinc oxide (ZnO) nanowires. It describes using a vapor-liquid-solid chemical vapor deposition method to grow ZnO nanowires on various substrates with diameters as small as 40nm. The document discusses controlling nanowire diameter and length, characterizing the nanowires' optical and electrical properties, and measuring their enhanced Young's modulus compared to bulk ZnO. Potential applications for ZnO nanowires include piezoelectric devices, field effect transistors, and nanogenerators.
1) The document discusses using silver nanoparticles to enhance Raman scattering signals through surface enhanced Raman spectroscopy (SERS) for studying heat transport in quantum dots.
2) Different methods for synthesizing silver nanoparticles were explored and nanoparticles were used to significantly enhance, by at least a factor of 90, the Raman signal of a test molecule (crystal violet).
3) For future work, the researchers want to use the silver nanoparticles to enhance Raman scattering from quantum dots to study heat transport in these nanomaterials.
Low Temperature Synthesis of ZnO Nanoparticlescurtistaylor80
This document summarizes a new low-temperature vapor phase transport process for synthesizing ZnO nanoparticles. ZnO powder and carbon are used as precursors and decomposed at temperatures as low as 225°C to form ZnO nanoparticles. Reaction conditions like time, temperature, and gas flow rate can be adjusted to control the nanoparticle size, with smaller sizes exhibiting stronger surface-related photoluminescence. This new method allows for the low-temperature physical synthesis of high-quality ZnO nanoparticles suitable for applications in flexible electronics and optoelectronics.
Evaluation of monocrystalline ZnSe as a high-temperature radiation detectorAndrii Sofiienko
This document evaluates monocrystalline ZnSe as a high-temperature radiation detector. It finds that undoped ZnSe crystals have an extremely low dark conductivity of around 200 pA at 150°C. Spectrometric measurements using a 57Co source show ZnSe can effectively detect gamma and X-rays with a counting efficiency close to maximum in the range of 500-750V between 20-130°C. The results indicate ZnSe can be used as an effective radiometric detector for gamma and X-rays over a wide temperature range up to at least 130°C.
This document evaluates monocrystalline ZnSe as a high-temperature radiation detector. It finds that undoped ZnSe crystals have an extremely low dark conductivity of around 200 pA at 150°C. Spectrometric measurements using a 57Co source show ZnSe can efficiently detect X-rays with a counting efficiency near the maximum value when the bias voltage is between 500-750V in temperatures from 20-130°C. The results indicate ZnSe can effectively be used as a gamma and X-ray radiation detector in a wide temperature range up to at least 130°C.
IRJET - Comparative Study on the Structural and Optical Characterization of Z...IRJET Journal
This document reports on a comparative study of the structural and optical characterization of zinc sulfide (ZnS) and zinc oxide (ZnO) nanoparticles. ZnS nanoparticles were prepared via chemical precipitation using zinc chloride, sodium sulfide, and mercaptoethanol as a capping agent. ZnO nanoparticles were prepared using zinc acetate, ammonia, and thiourea as a capping agent. X-ray diffraction and scanning electron microscopy were used to characterize particle size and structure. Absorption spectra showed a blue shift with decreasing particle size due to quantum confinement. Photoluminescence spectra were also studied. The results show ZnS particles were 2-7nm and ZnO particles were 50-60nm. Both
Fabrication, Structural and Optical Properties of Ni and Cr Doped ZnO Nanocom...IRJET Journal
This document summarizes research on the fabrication, structural, optical, and photocatalytic properties of undoped and Ni, Cr co-daped ZnO nanocomposites. The nanocomposites were synthesized via a facile precipitation method. X-ray diffraction analysis showed the nanocomposites crystallized in the hexagonal wurtzite structure without impurities. Scanning electron microscopy revealed the nanoparticles were uniformly distributed and spherical in shape, ranging in size from 25-44 nm. Ultraviolet-visible spectroscopy showed the optical bandgap decreased from 3.19 eV to 2.99 eV with doping, which is desirable for photocatalytic and optoelectronic applications. Photoluminescence spectroscopy
Analysis Of Carbon Nanotubes And Quantum Dots In A Photovoltaic Device Slide ...M. Faisal Halim
Francis' presentation to Louis Stokes Association for Minority Participation. Since I co-authored this work I think I have the right to a copy. I was the graduate student Francis was working with.
Potentiostatic Deposition of ZnO Nanowires: Effect of Applied Potential and Z...IJRES Journal
In this work we report on potentiostatic deposition of Zinc oxide (ZnO) nanowires on fluorine-doped tin oxide (FTO) covered glass substrates from electroreduction of molecular oxygen. The influence of applied deposition potential, and the concentrations of zinc precursor (ZnCl2) on the properties of ZnO nanowires was investigated.SEM results revealed that ZnO nanowires electrodeposited at applied potential -0.85Vhave high density and good alignment. The diameters and densities of the electrodeposited ZnO nanowires are strongly dependent on the zinc ion concentrations and well aligned nanowires with uniform diameter can be obtained when the concentration of zinc ions is between 0.5 mM and 1 mM.
This document summarizes the fabrication and characterization of nanowire devices. It discusses the early history of nanotechnology and how the field has progressed. Various methods for synthesizing semiconductor nanowires are described, including vapor-liquid-solid growth and electrodeposition. The document shows images of nanowires made from materials like copper, cadmium sulfide, and zinc oxide. It also discusses the unique electrical and optical properties of nanowires and their potential applications in areas such as electronics, optoelectronics, and sensing. In conclusion, the author remarks that nanowires may serve as important building blocks for next-generation electronic and optoelectronic systems by enabling new device concepts.
El documento describe los significados y asociaciones de los colores rojo, naranja y amarillo. El rojo es un color caliente que evoca emociones como el amor y la guerra. El naranja combina la energía del rojo con la alegría del amarillo. El amarillo simboliza la luz del sol y representa la felicidad y la energía. Cada color tiene diferentes asociaciones culturales y psicológicas.
Este documento describe estrategias para buscar y seleccionar información en entornos visuales como Internet. Explica la diferencia entre buscadores y metabuscadores, y da ejemplos de cada uno. También presenta el modelo Gavilán de cuatro pasos para guiar a estudiantes en la búsqueda de información, y define la competencia para manejar información.
Dokumen ini berisi iklan layanan jual beli spring bed dari toko springbedsurabaya.com yang berlokasi di Jalan Dukuh Kupang 25 no 37 Surabaya dengan nomor telepon 031-5617601. Toko ini menawarkan berbagai macam spring bed dengan harga terbaru dan menyarankan untuk memeriksa katalog harga lebih lanjut di website www.springbedsurabaya.com.
A mãe fez biscoitos para Lena e Beto. Muitas crianças vizinhas foram chegando e comendo os biscoitos. A cada vez que tocavam a campainha, dividiam os biscoitos restantes igualmente entre todos. No final, a vovó apareceu com mais biscoitos para que todos pudessem comer até a saciedade.
El documento presenta el modelo de negociación de Fisher y Ury, también conocido como el modelo de Harvard. Describe los pasos del análisis integral del proceso de negociación según este modelo, incluyendo identificar el problema, analizar sus posibles causas, seleccionar estrategias de solución y establecer planes de acción específicos. También enfatiza la importancia de una visión sistémica que considere la multiplicidad de factores interrelacionados en el proceso de negociación.
"ASP.NET Core est le nouveau framework Open Source et Cross Platform pour développer des applications connectées modernes : applications webs, backends mobiles ou applications IoT.
ASP.NET Core peut tourner sur .NET Core ou sur le .NET Framework complet. Son architecture a été complètement revue depuis la précédente génération du framework afin de fournir une expérience de développement plus moderne, plus flexible et plus performante.
Venez découvrir les bases d'ASP.NET Core afin de pouvoir l'envisager dans vos futurs projets !"
The document discusses the ELF file format and dynamic linking process. It describes the ELF header, program header table, and segments that make up an ELF file. The dynamic linker loads segments into memory, resolves symbols using hash tables, and initializes shared libraries and the main executable in the correct order. Symbol resolution involves determining the symbol hash, searching hash buckets in each library, and comparing names.
A few Curious Aspects of ZnO Nanostructures - Prof.Joy MitraSTS FORUM 2016
This document summarizes research on designing defects in ZnO nanostructures. It discusses how ZnO naturally forms with n-type doping due to oxygen vacancies and zinc interstitials. The researcher investigates controlling the ratio of zinc interstitials to oxygen vacancies to tune the material's optical and electrical properties. Photoluminescence and conductive atomic force microscopy experiments on ZnO nanorods with varying defect concentrations show changes in emission spectra and localized photoresponse correlated with grain structure. The findings provide insight into defect engineering of ZnO for optoelectronic applications.
ZnS Nanostructures: Synthesis, Characterization, and Theory - Defense Present...Daniel Moore
Daniel Moore's Ph.D. defense presentation summarizes his research on synthesizing and characterizing novel ZnS nanostructures. He discusses various ZnS nanostructures including nanobelts, aligned nanowires, nanohelices, and ultralong core-shell ZnS-SiO2 nanowires. Various growth mechanisms are proposed including vapor-liquid-solid and vapor-solid processes. Parameters like temperature, time, and catalyst are found to influence the morphology. Characterization using TEM, XRD and photoluminescence elucidate the crystal structure and composition of the nanostructures.
Synthesis And Characterization Of Individual ZnO NanowiresMartial Duchamp
This document summarizes research on synthesizing and characterizing individual zinc oxide (ZnO) nanowires. It describes using a vapor-liquid-solid chemical vapor deposition method to grow ZnO nanowires on various substrates with diameters as small as 40nm. The document discusses controlling nanowire diameter and length, characterizing the nanowires' optical and electrical properties, and measuring their enhanced Young's modulus compared to bulk ZnO. Potential applications for ZnO nanowires include piezoelectric devices, field effect transistors, and nanogenerators.
1) The document discusses using silver nanoparticles to enhance Raman scattering signals through surface enhanced Raman spectroscopy (SERS) for studying heat transport in quantum dots.
2) Different methods for synthesizing silver nanoparticles were explored and nanoparticles were used to significantly enhance, by at least a factor of 90, the Raman signal of a test molecule (crystal violet).
3) For future work, the researchers want to use the silver nanoparticles to enhance Raman scattering from quantum dots to study heat transport in these nanomaterials.
Low Temperature Synthesis of ZnO Nanoparticlescurtistaylor80
This document summarizes a new low-temperature vapor phase transport process for synthesizing ZnO nanoparticles. ZnO powder and carbon are used as precursors and decomposed at temperatures as low as 225°C to form ZnO nanoparticles. Reaction conditions like time, temperature, and gas flow rate can be adjusted to control the nanoparticle size, with smaller sizes exhibiting stronger surface-related photoluminescence. This new method allows for the low-temperature physical synthesis of high-quality ZnO nanoparticles suitable for applications in flexible electronics and optoelectronics.
Evaluation of monocrystalline ZnSe as a high-temperature radiation detectorAndrii Sofiienko
This document evaluates monocrystalline ZnSe as a high-temperature radiation detector. It finds that undoped ZnSe crystals have an extremely low dark conductivity of around 200 pA at 150°C. Spectrometric measurements using a 57Co source show ZnSe can effectively detect gamma and X-rays with a counting efficiency close to maximum in the range of 500-750V between 20-130°C. The results indicate ZnSe can be used as an effective radiometric detector for gamma and X-rays over a wide temperature range up to at least 130°C.
This document evaluates monocrystalline ZnSe as a high-temperature radiation detector. It finds that undoped ZnSe crystals have an extremely low dark conductivity of around 200 pA at 150°C. Spectrometric measurements using a 57Co source show ZnSe can efficiently detect X-rays with a counting efficiency near the maximum value when the bias voltage is between 500-750V in temperatures from 20-130°C. The results indicate ZnSe can effectively be used as a gamma and X-ray radiation detector in a wide temperature range up to at least 130°C.
IRJET - Comparative Study on the Structural and Optical Characterization of Z...IRJET Journal
This document reports on a comparative study of the structural and optical characterization of zinc sulfide (ZnS) and zinc oxide (ZnO) nanoparticles. ZnS nanoparticles were prepared via chemical precipitation using zinc chloride, sodium sulfide, and mercaptoethanol as a capping agent. ZnO nanoparticles were prepared using zinc acetate, ammonia, and thiourea as a capping agent. X-ray diffraction and scanning electron microscopy were used to characterize particle size and structure. Absorption spectra showed a blue shift with decreasing particle size due to quantum confinement. Photoluminescence spectra were also studied. The results show ZnS particles were 2-7nm and ZnO particles were 50-60nm. Both
Fabrication, Structural and Optical Properties of Ni and Cr Doped ZnO Nanocom...IRJET Journal
This document summarizes research on the fabrication, structural, optical, and photocatalytic properties of undoped and Ni, Cr co-daped ZnO nanocomposites. The nanocomposites were synthesized via a facile precipitation method. X-ray diffraction analysis showed the nanocomposites crystallized in the hexagonal wurtzite structure without impurities. Scanning electron microscopy revealed the nanoparticles were uniformly distributed and spherical in shape, ranging in size from 25-44 nm. Ultraviolet-visible spectroscopy showed the optical bandgap decreased from 3.19 eV to 2.99 eV with doping, which is desirable for photocatalytic and optoelectronic applications. Photoluminescence spectroscopy
Analysis Of Carbon Nanotubes And Quantum Dots In A Photovoltaic Device Slide ...M. Faisal Halim
Francis' presentation to Louis Stokes Association for Minority Participation. Since I co-authored this work I think I have the right to a copy. I was the graduate student Francis was working with.
Potentiostatic Deposition of ZnO Nanowires: Effect of Applied Potential and Z...IJRES Journal
In this work we report on potentiostatic deposition of Zinc oxide (ZnO) nanowires on fluorine-doped tin oxide (FTO) covered glass substrates from electroreduction of molecular oxygen. The influence of applied deposition potential, and the concentrations of zinc precursor (ZnCl2) on the properties of ZnO nanowires was investigated.SEM results revealed that ZnO nanowires electrodeposited at applied potential -0.85Vhave high density and good alignment. The diameters and densities of the electrodeposited ZnO nanowires are strongly dependent on the zinc ion concentrations and well aligned nanowires with uniform diameter can be obtained when the concentration of zinc ions is between 0.5 mM and 1 mM.
This document summarizes the fabrication and characterization of nanowire devices. It discusses the early history of nanotechnology and how the field has progressed. Various methods for synthesizing semiconductor nanowires are described, including vapor-liquid-solid growth and electrodeposition. The document shows images of nanowires made from materials like copper, cadmium sulfide, and zinc oxide. It also discusses the unique electrical and optical properties of nanowires and their potential applications in areas such as electronics, optoelectronics, and sensing. In conclusion, the author remarks that nanowires may serve as important building blocks for next-generation electronic and optoelectronic systems by enabling new device concepts.
This document summarizes research on Au/TiO2 nanoparticle catalysts. It describes the preparation of Au/TiO2 nanoparticles using laser vaporization and solution deposition methods. The document outlines objectives to understand size and loading effects on catalyst performance and the reaction mechanism. It then details various characterization techniques used such as CO oxidation activity screening, XPS analysis, and electron microscopy to analyze the Au/TiO2 nanoparticles.
This to demonstrate the laser ablation of hard materials to form a thin film for optical sensors. The work was done at DIllard University , New Orleans LA by Professor Abdalla Darwish. any comment e-mail adarwish@bellsouth.net.
Introduction to nanoscience and nanotechnologyaimanmukhtar1
Introduction of nanoscience/nanotechnology ,properties/potential applications of nanomaterials and electrodeposition of metal single component and alloy nanowires in AAO template
Ultra smooth and lattice relaxed zn o thin films [eid]Eid Elsayed
The crystal structure and quality of ZnO thin films were enhanced by high temperature vacuum annealing. 150 nm thick ZnO films were deposited on a-plane sapphire substrates by RF sputtering at 600°C and then annealed in situ at temperatures from 700°C to 900°C. Higher annealing temperatures produced smoother films with root mean square roughness reaching 0.3 nm at 850°C. Raman spectroscopy showed the A1(TO) mode at all annealing temperatures and the A1(LO) mode appeared above 800°C, indicating improved crystal quality. X-ray diffraction revealed narrower diffraction peaks and a relaxed lattice constant matching bulk ZnO at 900°C annealing, demonstrating high quality c-axis oriented epit
Presented by Peng Zuo at International Conference on Crystal Growth and Epitaxy (ICCGE-19) in Keystone CO, July 28-August 2, 2019.
Solid phase epitaxy (SPE) is a promising approach for expanding the applications of epitaxial complex oxides by providing access to a broader range of compositions and enabling their formation in complex geometries. The SPE of PrAlO3 on SrTiO3 serves as a model system. The interfaces between lanthanide aluminates and SrTiO3 are also of practical interest because these interfaces can host a two-dimensional electron gas. Amorphous PrAlO3 layers were deposited on the SrTiO3 (001) by atomic layer deposition using tris(isopropylcyclopentadienyl)praseodymium (Pr(C5H4iPr)3), trimethylaluminum (AlMe3) and water.
Similar to Conclusion of the experiment in canada! (20)
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
2. WZ ZnO
ZB ZnSe
2.8 eV
3.2 eV
1.9 eV
Feature
・Type-II heterojunction
・ZnSe and ZnO have a wide bandgap
・Lattice mismatched combinations
WZ ZnO
WZ ZnSe
2.8 eV
3.2 eV
1.5 eV
For Photovoltaic devices
Increase surface-to-volume-ratio
3. Chemical Vapor Deposition (CVD) method
Quartz tube heater
Au on Si substrate ZnO/C or ZnSe
Ar Gas inletAr Gas outlet
0
200
400
600
800
1000
1200
0 10 20 30 40 50 60
Temperature[℃]
Position [cm]
4. Two-step CVD method
Au
Si ZnO
Si
First step Second step
ZnSe
Si
ZnSe
Si
ZnO
Si
ZnO/ZnSe Core/Shell NW
ZnO ZnSe Branch NW
Si
5. Growth conditions of ZnO/ZnSe core/shell NWs
Au
Si
ZnO
Si
ZnSe
Si
Temperature Duration Ar gas flow rate
First step 600 ℃ 60 min 125sccm
Second step 590 ℃ 60 min 235sccm
Source material : ZnO (99.99%) and C(99.9%) with the
weight ratio of 1:1
: ZnSe (99.99%)
Thickness of Au film : 10 nm
6. SEM image
ZnO NWs ZnO/ZnSe core/ shell NWs
The average NW diameter : 40 nm → 75 nm
500 nm 500 nm
1 μm 2 μm
8. Photoluminescence Spectrum
ZnO Bandedge (BE) emission : 380 nm = 3.26 eV
ZnSe BE emission : 460 nm = 2.69 eV
ZnSe Deep Level (DL) emission: 640 nm = 1.93 eV
Laser wavelength : 361.2 nm
Room temperature
9. Growth conditions of ZnO ZnSe branch NWs
Au
Si
Temperatu𝐫𝐞 Duration Ar gas flow rate
First step 640 ℃ 60 min 235sccm
Second step 590 ℃ 60 min 125sccm
ZnSe
Si
ZnO
Si
Source material : ZnO (99.99%) and C(99.9%) with the
weight ratio of 1:1
ZnSe (99.99%)
Thickness of Au film : 10 nm
10. SEM image
ZnSe NWs ZnO ZnSe branch NWs
The average diameter of thin NWs is 29 nm → 33 nm
5 μm 5 μm
1 μm 1 μm
12. PL
ZnSe BE emission : 442 nm = 2.8 eV
ZnSe DL emission : 640 nm = 1.9 eV
ZnO BE emission : 380 nm =3.26 eV
Laser wavelength : 361.2 nm
Room temperature
13. ・ Characterize the ZnO/ZnSe core/shell NWs and ZnO ZnSe branch NW
by XRD and PL
・ Observe the surface morphology of ZnO/ZnSe core/shell NW, and ZnO
ZnSe branch heterostructure NW by SEM
・ Found the conditions for growth ZnO/ZnSe core/shell heterostructure
NW, and ZnO ZnSe branch heterostructure NW
14. Future Work
・ Measure the electrical property by Electron beam induced current
・ Fabricate the single NW device with ZnO ZnSe branch structure NW
by electron beam lithography
・ Upgrade the quality of ZnO and ZnSe NWs before growth second
material
・ Measure the junction of ZnO and ZnSe by transmission electron
microscopy to confirm ZnO NWs are connecting to ZnSe NWs
15. Acknowledgement
・ I would like to express my deep gratitude to Professor Harry E. Ruda,
for his patient guidance and useful critiques of this research work.
・ I would also like to thank Dr. Carlos Fernandes, for his advice and
assistance in keeping my progress on schedule.
・ I would also like to thank Dr Souza Christina and Dave Wisnieski for
measuring PL spectrum and teaching me how to analyze spectrum.
・ I wish to express my sincere gratitude to all of the concerned people,
who help me to finish my all procedure, correct my English, promote my
experiments.
17. Analysis
The mean diameter of base : 223 nm
The mean diameter of branch : 52 nm
The diameter of ZnO was also almost 40 nm
18. ZnSe : June 28
ZnO : July 4
ZnO ZnSe branch NW data by EDX line profile
①
②
②
①
There is the ZnSe ZnO hetero structure NW
19. My opinion
I measured 20 NWs by ESM and EDX. The compositions of thin NWs were ZnSe
ZnO NWs weren’t grown on ZnSe NWs
ZnO
Au
ZnSe
Before using EDX,
I guessed this structure
ZnO
ZnSe
After using EDX, I believe it was happened in the furnace
Type Ⅱ heterojunction
Bandgap diagram
National Renewable Energy Laboratory
格子ミスマッチ→キャリア伝導に寄与
To grow the NW, I use a chemical vapor deposition method. Before growth NWs, As preparation of Au deposition , I prepare Si substrates, which is (100) p-type, and clean up the surface and get rid of the oxide layer using Aseton, IPA, DI water, and Hydrofluoric, and then deposit 10 nm Au film on the Si substrate by a thermal evaporation method. Au help growth of NWs as a catalyst.
そして、Ar gas を流す。Ar gus was introduced into the tube.
I use a two steps chemical vapor deposition method
In the first step, I prepared source materials of ZnO and C with mass ration of 1 to 1.
I deposit the 10 nm of the Au film on the Si substrate, as the catalyst.
the ZnSe films were prepared by vacuum evaporation method under the pressure better than 10-5 Torr on chemically cleaned glass substrates from 99.99% pure
ZnSe powder (Aldrich) using molybdenum boat.
右上 top right
Look at the bottom two pictures
The SEM images on the left side is before growing ZnSe NWs, right side is after growing ZnO NWs on the ZnSe NWs
This is the PL spectrum data from ZnO and ZnO/ZnSe core/shell NWs. Basically, There is a ZnSe DL emission.
As shown in enlarged figure, There is a slightly ZnO BE emission.
The top Left and the top right are the same magnification. The bottom ones as well.
There is the BE emission, also the strong DL emission observed
I’d like to thank you (for 〜)
I measure the Reduction of source materials each time