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Book Fabrication of Zinc Nitride Thin Films Using RF Magnetron Sputtering Deposition for Optoelectronic Applications

Download or read book Fabrication of Zinc Nitride Thin Films Using RF Magnetron Sputtering Deposition for Optoelectronic Applications written by Ting Wen and published by . This book was released on 2012 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc nitride thin films possess a small optical band gap with direct transition, low resistivity, high mobility and carrier concentration. Therefore, it may be suitable as an optoelectronic material for infrared sensors, smart windows and energy conversion devices. The objective of this work is to grow zinc nitride thin films using RF magnetron sputtering, understand its mechanical, optical, and electrical properties, and investigate its performance as light sensing devices. Synthesis and characterization of zinc nitride thin films has been investigated in this work. An RF magnetron sputtering deposition was employed to synthesize zinc nitride thin films using pure metal zinc target in either N2-Ar or N2-Ar-H2 mixtures. The microstructural, optical and electrical characterizations of the representative films were investigated with stylus profilometry, XRD, AFM, SEM, TEM, UV-VIS-NIR double beam spectrometry, and Hall effect measurement. The photoresponse of the zinc nitride photoconductors was also studied under the irradiation of white light and NIR light. The as-deposited zinc nitride thin films were relatively soft and densely packed with smooth surface. It possesses a narrow optical band gap in the NIR range with direct transition. The zinc nitride showed n-type conductivity with low resistivity and high carrier concentration. To study the RF discharge power effect, the zinc nitride thin films were synthesized at different discharge powers densities. With discharge power density increasing, the film deposition rate increased, and the zinc nitride films acquired better crystalline structure, smaller optical band gap and less oxygen contaminations. After thermal annealing at moderate temperatures in either air or O2, the annealed zinc nitride thin films were photoconductive under irradiation of both NIR light and white light. The largest photoresponse and fastest response times were measured at the room temperature for the zinc nitride thin films annealed at 300 degree in the air. Hydrogen inclusion can modify the electrical and optical properties of crystalline semiconductor films by introducing impurity donor states. The ZnNx:H films deposited in N2-Ar-H2 mixture acquired less oxygen contamination and higher relative nitrogen atom concentration than the ZnNx films deposited in N2-Ar mixture. The as-deposited ZnNx:H films showed a clear photonic behavior under white light irradiation, and the annealed ZnNx:H films exhibited a pronounced change in resistance under both white light and NIR light irradiation comparing to the annealed ZnNx films. This was the first time to report photoresponse of zinc nitride thin films fabricated by reactive sputtering method. The photoconductivity was gradually improved by optimization of deposition conditions, annealing conditions and film compositions.

Book Journal of Applied Physics

Download or read book Journal of Applied Physics written by and published by . This book was released on 2003 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Chemical Solution Deposition of Functional Oxide Thin Films

Download or read book Chemical Solution Deposition of Functional Oxide Thin Films written by Theodor Schneller and published by Springer Science & Business Media. This book was released on 2014-01-24 with total page 801 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first text to cover all aspects of solution processed functional oxide thin-films. Chemical Solution Deposition (CSD) comprises all solution based thin- film deposition techniques, which involve chemical reactions of precursors during the formation of the oxide films, i. e. sol-gel type routes, metallo-organic decomposition routes, hybrid routes, etc. While the development of sol-gel type processes for optical coatings on glass by silicon dioxide and titanium dioxide dates from the mid-20th century, the first CSD derived electronic oxide thin films, such as lead zirconate titanate, were prepared in the 1980’s. Since then CSD has emerged as a highly flexible and cost-effective technique for the fabrication of a very wide variety of functional oxide thin films. Application areas include, for example, integrated dielectric capacitors, ferroelectric random access memories, pyroelectric infrared detectors, piezoelectric micro-electromechanical systems, antireflective coatings, optical filters, conducting-, transparent conducting-, and superconducting layers, luminescent coatings, gas sensors, thin film solid-oxide fuel cells, and photoelectrocatalytic solar cells. In the appendix detailed “cooking recipes” for selected material systems are offered.

Book Tin Oxide Indium Tin Oxide Thin Films for Photovotaic Application

Download or read book Tin Oxide Indium Tin Oxide Thin Films for Photovotaic Application written by Anshuman Borthakur and published by LAP Lambert Academic Publishing. This book was released on 2014-04 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: With dwindling energy reserves, Photovoltaic(PV) module which is one of the most promising renewable sources of energy is slowly becoming indispensable for world's electricity production paradigm. Due to the low electrical resistance and high optical transparency in the visible range of the electromagnetic spectrum, Transparent Conducting Oxide (TCO) thin film(TF)s have found application as window electrode for fabrication of solar cell. Besides TCOs have wide application in display devices and other optoelectronic devices. This book mainly focuses on the fabrication and study of the optoelectronic properties of TCO thin films with special reference to PV application. This book also includes the fabrication and study of a heterojunction II-VI semiconductor solar cell using TCO as front electrode. It also highlights different methods used for the study of optoelectrical and structural properties of TF (e.g. SEM, XRD, thickness measurement, optical band gap, mobility, determination of carrier type, carrier concentration, conductivity etc.). This book is designed to serve as a handbook for the beginners who want to work in the field of thin film technology.

Book Reactive Sputtering Deposition and Characterization of Zinc Nitride and Oxy nitride Films for Electronic and Photovoltaic Applications

Download or read book Reactive Sputtering Deposition and Characterization of Zinc Nitride and Oxy nitride Films for Electronic and Photovoltaic Applications written by Nanke Jiang and published by . This book was released on 2013 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents a study on the fabrication of zinc nitride and zinc oxy-nitride films, and related hetero-structures on glass, silicon and other substrates. The goals of this study include gaining fundamental understanding on the electrical and optical properties, the chemical-bonding states and the micro-structure of these materials and examining their potential for photovoltaic and other electronic and optoelectronic applications. Reactive radio-frequency (RF) magnetron sputtering was used as the deposition method, which potentially enables control of composition of the thin films, as well as fabrication of multilayer structures for the study of possible hetero-junctions between zinc nitride and zinc oxy-nitrides. Along with reactive sputtering, several other fabrication methods, such as thermal evaporation and solution (e.g. silver or carbon paste) painting, were used as auxiliaries where necessary. The characterization techniques employed include (i) x-ray based techniques (x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), energy dispersive x-ray spectroscopy (EDXS)), (ii) optical based methods (spectroscopic ellipsometry (SE), optical spectrophotometry, Raman spectroscopy), (iii) scanning electron microscopy (SEM), and (iv) electrical measurements (resistivity, Hall effect measurements, current-voltage and photovoltaic measurements). The cross-correlation between the deposition/post-deposition conditions and the physical properties of the films was investigated. The deposition conditions, such as the nitrogen (or oxygen) partial concentration in the sputtering gas mixture, substrate temperatures, total deposition pressure, as well as the post-deposition treatments such as thermal treatment and/or oxidation in ambient, were studied in detail. Zinc nitride, with a small fraction of "naturally" incorporated oxygen, is found to be a promising candidate for photovoltaic applications because of its optical and electrical properties. Also, the capability of property tuning for the zinc oxy-nitride material system was demonstrated by intentionally introducing varied amount oxygen into zinc nitride. In order to better understand the crystalline structure and the electronic band structure of these materials, first principle density functional theory (DFT) was used for computations of pure zinc nitride and the doping effects in it with both native elements (Zn, N) and copper family elements (Cu, Ag, Au) as possible p-type dopants. Atomic geometry, formation energy, as well as electronic structure of defects in zinc nitride were studied and a general consistency was observed between theoretically calculated and experimentally determined results. Defect density of states (DOS) suggest that among all three studied copper-family elements, copper is a good candidate for a p-type dopant. Technological insight and approaches to the fabrication of device-relevant structures were the other important outcomes of this work. Our studies showed that the fabrication of device-relevant ohmic contacts, rectifying metal-nitride junctions and p-n junctions was possible. Substantial photovoltaic action was observed in a single junction solar cell configuration that uses p-type zinc oxy-nitride as an absorber layer.

Book Thinfilm Schottky Barriers and Heterojunctions

Download or read book Thinfilm Schottky Barriers and Heterojunctions written by Sumbit Chaliha and published by LAP Lambert Academic Publishing. This book was released on 2012-03 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor thin films and their junctions such as metal-semiconductor (Schottky barrier) and heterojunctions have received much attention due to their applications in various electronic and optoelectronic devices including solar cells. This book is based on the electrical and optical studies of thin film Schottky barriers and heterojunctions with an aim to use in optoelectronic devices. In this work, two wide band gap semiconductors, one Zinc Selenide (ZnSe) from group II-VI, and another transparent conducting oxide, Indium Tin Oxide are investigated in the forms of thin films and their junctions, for the possible uses as photovoltaic converter. The structural, morphological, optical and electrical (in dark and under illumination) properties of ZnSe and ITO thin films prepared at different growth conditions by thermal evaporation method have been studied by applying different experimental techniques. Schottky barriers and heterojunctions of ZnSe with different barrier metals and semiconductors have been fabricated and their current-voltage and photovoltaic characteristics are studied. The findings of it presented in this book will be helpful for the researchers of this field.

Book Investigation of Oxide Semiconductor Based Thin Films

Download or read book Investigation of Oxide Semiconductor Based Thin Films written by Meena Suhanya Rajachidambaram and published by . This book was released on 2012 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructured ZnO films were obtained via thermal oxidation of thin films formed with metallic Zn-nanoparticle dispersions. Commercial zinc nanoparticles used for this work were characterized by microscopic and thermal analysis methods to analyze the Zn-ZnO core shell structure, surface morphology and oxidation characteristics. These dispersions were spin-coated on SiO2/Si substrates and then annealed in air between 100 and 600 °C. Significant nanostructural changes were observed for the resulting films, particularly those from larger Zn nanoparticles. These nanostructures, including nanoneedles and nanorods, were likely formed due to fracturing of ZnO outer shell due to differential thermal expansion between the Zn core and the ZnO shell. At temperatures above 227 °C, the metallic Zn has a high vapor pressure leading to high mass transport through these defects. Ultimately the Zn vapor rapidly oxidizes in air to form the ZnO nanostructures. We have found that the resulting films annealed above 400 °C had high electrical resistivity. The zinc nanoparticles were incorporated into zinc indium oxide solution and spin-coated to form thin film transistor (TFT) test structures to evaluate the potential of forming nanostructured field effect sensors using simple solution processing. The functionalization of zinc tin oxide (ZTO) films with self-assembled monolayers (SAMs) of n-hexylphosphonic acid (n-HPA) was investigated. The n-HPA modified ZTO surfaces were characterized using contact angle measurement, x-ray photoelectron spectroscopy (XPS) and electrical measurements. High contact angles were obtained suggesting high surface coverage of n-HPA on the ZTO films, which was also confirmed using XPS. The impact of n-HPA functionalization on the stability of ZTO TFTs was investigated. The n-HPA functionalized ZTO TFTs were either measured directly after drying or after post-annealing at 140 °C for 48 hours in flowing nitrogen. Their electrical characteristics were compared with that of non-functionalized ZTO reference TFTs fabricated using identical conditions. We found that the non-functionalized devices had a significant turn-on voltage (V[subscript ON]) shift of ~0.9 V and ~1.5 V for the non-annealed and the post-annealed conditions under positive gate bias stress for 10,000 seconds. The n-HPA modified devices showed very minimal shift in V[subscript ON] (0.1 V), regardless of post-thermal treatment. The VON instabilities were attributed to the interaction of species from the ambient atmosphere with the exposed ZTO back channel during gate voltage stress. These species can either accept or donate electrons resulting in changes in the channel conductance with respect to the applied stress.

Book Investigation of Magnesium Indium Oxide Thin Film Fabricated by RF Sputtering System and Their Optoelectronics Applications

Download or read book Investigation of Magnesium Indium Oxide Thin Film Fabricated by RF Sputtering System and Their Optoelectronics Applications written by 陳維德 and published by . This book was released on 2020 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Thin Films and Heterostructures for Oxide Electronics

Download or read book Thin Films and Heterostructures for Oxide Electronics written by Satishchandra B. Ogale and published by Springer Science & Business Media. This book was released on 2005-11-21 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oxides form a broad subject area of research and technology development which encompasses different disciplines such as materials science, solid state chemistry, physics etc. The aim of this book is to demonstrate the interplay of these fields and to provide an introduction to the techniques and methodologies involving film growth, characterization and device processing. The literature in this field is thus fairly scattered in different research journals covering one or the other aspect of the specific activity. This situation calls for a book that will consolidate this information and thus enable a beginner as well as an expert to get an overall perspective of the field, its foundations, and its projected progress.

Book Optimisation of ZnO Thin Films

Download or read book Optimisation of ZnO Thin Films written by Saurabh Nagar and published by Springer. This book was released on 2017-05-22 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph describes the different implantation mechanisms which can be used to achieve strong, reliable and stable p-type ZnO thin films. The results will prove useful in the field of optoelectronics in the UV region. This book will prove useful to research scholars and professionals working on doping and implantation of ZnO thin films and subsequently fabricating optoelectronic devices. The first chapter of the monograph emphasises the importance of ZnO in the field of optoelectronics for ultraviolet (UV) region and also discusses the material, electronic and optical properties of ZnO. The book then goes on to discuss the optimization of pulsed laser deposited (PLD) ZnO thin films in order to make successful p-type films. This can enable achievement of high optical output required for high-efficiency devices. The book also discusses a hydrogen implantation study on the optimized films to confirm whether the implantation leads to improvement in the optimized results.

Book Sputtered Indium Tin Oxide Films for Optoelectronic Applications

Download or read book Sputtered Indium Tin Oxide Films for Optoelectronic Applications written by Oleksandr Malik and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High-quality indium tin oxide (ITO) films have been fabricated using a DC sputtering technique in a pure argon atmosphere with a postannealing in an oxygen environment at atmosphere pressure. Structural, morphological, and electro-optical parameters of the ITO films were studied at different annealing temperatures for the films fabricated on two types of glass substrates, soda lime and alkali-free substrates. A comparative analysis shows that low-cost soda lime substrates are suitable for the fabrication of high-quality nanocrystalline ITO films after annealing them at 300°C. This result is of great importance for reducing the cost of thin film solar cells, in which ITO films serve as transparent conducting electrodes. We present a comparison of the properties of sputtered ITO films with those fabricated using a spray pyrolysis deposition technique, which is useful for some optoelectronic applications.