Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Investigation of Silicon Zinc Tin Oxide Thin Films and Their Optoelectrical Applications Fabricated by RF Sputtering
Author: Investigation of Zinc Tin Oxide Thin Films and Their Optoelectrical Applications Fabricated by RF Sputtering System
Author: 楊宸權Investigation of Zinc Tin Oxide Thin Films and Their UV Optoelectrical Devices Fabricated by RF Sputtering
Author: Fabrication of Zinc Nitride Thin Films Using RF Magnetron Sputtering Deposition for Optoelectronic Applications
Author: Ting WenPublisher:
ISBN:
Category : Optoelectronics
Languages : en
Pages : 122
Book Description
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.
Journal of Applied Physics
Author: Chemical Solution Deposition of Functional Oxide Thin Films
Author: Theodor SchnellerPublisher: Springer Science & Business Media
ISBN: 3211993118
Category : Technology & Engineering
Languages : en
Pages : 801
Book Description
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.
Reactive Sputtering Deposition and Characterization of Zinc Nitride and Oxy-nitride Films for Electronic and Photovoltaic Applications
Author: Nanke JiangPublisher:
ISBN:
Category : Photovoltaic cells
Languages : en
Pages : 144
Book Description
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.
Investigation of Indium Tungsten Oxide Thin Film Fabricated by RF Sputtering System and Their Applications
Author: 陳冠吟Thinfilm Schottky Barriers and Heterojunctions
Author: Sumbit ChalihaPublisher: LAP Lambert Academic Publishing
ISBN: 9783848429653
Category :
Languages : en
Pages : 276
Book Description
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.
Silicon Heterojunction Solar Cells
Author: W.R. FahrnerPublisher: Trans Tech Publications Ltd
ISBN: 3038131024
Category : Technology & Engineering
Languages : en
Pages : 208
Book Description
The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made to reduce the production costs of conventional solar cells (manufactured from monocrystalline silicon using diffusion methods) by instead using cheaper grades of silicon, and simpler pn-junction fabrication. That is the hero of this book; the heterojunction solar cell.