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1
Maciel, Júnior Jorge Luiz Barbosa. "Investigação de propriedades de filmes finos de Sn'O IND. 2' e 'Al IND. 2''O IND. 3' para aplicação em dispositivos /." Bauru : [s.n.], 2010. http://hdl.handle.net/11449/88456.
Повний текст джерелаАнотація:
Orientador: Luis Vicente de Andrade ScalviBanca: Margarida Juri Saeki
Banca: Tomaz Catunda
O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp
Resumo: A proposta deste trabalho é a investigação das propriedades elétricas e ópticas de filmes finos de dióxido de estanho (Sn'O IND. 2') obtidos via sol-gel e por solução alcoólica depositados via dip-coating, e, filmes de alumina ('Al IND. 2''O IND. 3') obtidos por deposição de filmes de alumínio (Al) via evaporação resistiva e tratamento térmico em diferentes ambientes, para promover a oxidação de Al. A investigação individual quanto às propriedades ópticas e elétricas desses materiais conhecer seu comportamento na forma de filmes, e estudar a região interfacial de Sn'O IND. 2' e 'Al IND. 2''O IND. 3'. As caracterizações estruturais dos filmes foram feitas por difração de raios-X (DRX), e, no caso dos filmes de alumina, utilizou-se também microscopia eletrônica de varredura (MEV) e microscopia óptica. Nas caracterizações ópticas foram utilizadas técnicas de espectroscopia na região do ultravioleta e no infravermelho próximo (UV-Vis-Nir). Tanto os filmes obtidos por meio alcoólico como obtidos via SGDC foram caracterizados como sendo de Sn'O IND. 2' de estrutura tetragonal do tipo rutilo, sendo que os filmes obtidos via processo alcoólico apresentaram condutividade elétrica maior do que os filmes obtidos via SGDC. Os resultados referentes aos filmes finos de alumínio indicam que independentemente da quantidade de camadas de alumínio depositadas e da atmosfera de tratamento térmico, tem-se a oxidação do alumínio à alumina ('Al IND. 2''O IND. 3'), sendo que a estrutura dominante depende da atmosfera de tratamento. A sua utilização como camada isolante no gate em dispositivo metal-óxido-semicondutor é viável, pois a corrente fonte-dreno apresenta valores significativamente maiores do que a corrente fonte-gate.
Abstract: The main goal of this work is the investigation of properties of tin dioxide (Sn'O IND. 2') and alumina ('Al IND. 2''O IND. 3) thin films. The first one was obtained through the sol-gel process as well as alcoholic solution, via dip-coating. The alumina thin films were obtained by resistive evaporation of aluminum (Al) followed by thermal annealing in distinct atmospheres, to promote the Al oxidation. The individual investigation of optical and electrical properties of these materials aims the knowledge of their behavior as thin films, which allows studying the interface layer of the heterojunction Sn'O IND. 2' e 'Al IND. 2''O IND. 3'. Structural characterization of films was carried out by X-ray diffraction (XRD) technique and particularly on the alumina films, scanning electron microscopy (SEM) and optical microscopy were done. For the optical characterization, wide spectra were obtained, with spectroscopy from ultraviolet to near infrared (UV-Vis-Nir). Either the films obtained in the alcoholic solution as well as via SGDC, where characterized as Sn'O IND. 2' of tetragonal structure of rutile type, and the films obtained through alcoholic process present electrical conductivity higher than the films obtained via SGDC. Results on aluminum thin films indicate that independent on the amount of deposited aluminum and thermal annealing atmosphere, the oxidation of aluminum to alumina ('Al IND. 2''O IND. 3) takes place, but the dominant alumina structure depends on the thermal annealing atmosphere. Besides, its utilization as insulating layer at the gate of a metal-oxide semicondutor device is achievable, because the source-drain current is significantly higher than the source-gate current.
Mestre
2
Maciel, Júnior Jorge Luiz Barbosa [UNESP]. "Investigação de propriedades de filmes finos de Sn'O IND. 2' e 'Al IND. 2''O IND. 3' para aplicação em dispositivos." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/88456.
Повний текст джерелаАнотація:
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A proposta deste trabalho é a investigação das propriedades elétricas e ópticas de filmes finos de dióxido de estanho (Sn'O IND. 2') obtidos via sol-gel e por solução alcoólica depositados via dip-coating, e, filmes de alumina ('Al IND. 2''O IND. 3') obtidos por deposição de filmes de alumínio (Al) via evaporação resistiva e tratamento térmico em diferentes ambientes, para promover a oxidação de Al. A investigação individual quanto às propriedades ópticas e elétricas desses materiais conhecer seu comportamento na forma de filmes, e estudar a região interfacial de Sn'O IND. 2' e 'Al IND. 2''O IND. 3'. As caracterizações estruturais dos filmes foram feitas por difração de raios-X (DRX), e, no caso dos filmes de alumina, utilizou-se também microscopia eletrônica de varredura (MEV) e microscopia óptica. Nas caracterizações ópticas foram utilizadas técnicas de espectroscopia na região do ultravioleta e no infravermelho próximo (UV-Vis-Nir). Tanto os filmes obtidos por meio alcoólico como obtidos via SGDC foram caracterizados como sendo de Sn'O IND. 2' de estrutura tetragonal do tipo rutilo, sendo que os filmes obtidos via processo alcoólico apresentaram condutividade elétrica maior do que os filmes obtidos via SGDC. Os resultados referentes aos filmes finos de alumínio indicam que independentemente da quantidade de camadas de alumínio depositadas e da atmosfera de tratamento térmico, tem-se a oxidação do alumínio à alumina ('Al IND. 2''O IND. 3'), sendo que a estrutura dominante depende da atmosfera de tratamento. A sua utilização como camada isolante no gate em dispositivo metal-óxido-semicondutor é viável, pois a corrente fonte-dreno apresenta valores significativamente maiores do que a corrente fonte-gate.
The main goal of this work is the investigation of properties of tin dioxide (Sn'O IND. 2') and alumina ('Al IND. 2''O IND. 3) thin films. The first one was obtained through the sol-gel process as well as alcoholic solution, via dip-coating. The alumina thin films were obtained by resistive evaporation of aluminum (Al) followed by thermal annealing in distinct atmospheres, to promote the Al oxidation. The individual investigation of optical and electrical properties of these materials aims the knowledge of their behavior as thin films, which allows studying the interface layer of the heterojunction Sn'O IND. 2' e 'Al IND. 2''O IND. 3'. Structural characterization of films was carried out by X-ray diffraction (XRD) technique and particularly on the alumina films, scanning electron microscopy (SEM) and optical microscopy were done. For the optical characterization, wide spectra were obtained, with spectroscopy from ultraviolet to near infrared (UV-Vis-Nir). Either the films obtained in the alcoholic solution as well as via SGDC, where characterized as Sn'O IND. 2' of tetragonal structure of rutile type, and the films obtained through alcoholic process present electrical conductivity higher than the films obtained via SGDC. Results on aluminum thin films indicate that independent on the amount of deposited aluminum and thermal annealing atmosphere, the oxidation of aluminum to alumina ('Al IND. 2''O IND. 3) takes place, but the dominant alumina structure depends on the thermal annealing atmosphere. Besides, its utilization as insulating layer at the gate of a metal-oxide semicondutor device is achievable, because the source-drain current is significantly higher than the source-gate current.
3
Hild, Florent. "Étude de la structure et des propriétés optiques de couches minces d’oxydes d’étain dopés avec des terres rares (Ce, Tb, Yb)." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0294/document.
Повний текст джерелаАнотація:
Ce travail de thèse concerne l’élaboration et la caractérisation structurale de couches minces d’oxyde d’étain dopées avec des terres rares ainsi que l’étude de leurs propriétés de photoluminescence. Les couches sont dopées avec du cérium, du terbium ou de l’ytterbium. Les films sont élaborés par évaporation sous vide d’une poudre de SnO2 sur un substrat de silicium monocristallin, et nécessitent un recuit post-dépôt à 600°C à l’air pour cristalliser en phase SnO2 de type rutile. Dans une première partie du travail a consisté caractériser le matériau non dopé. La caractérisation microstructurale a révélé qu’une oxydation du substrat conduisant à une réaction entre l’oxyde d’étain et le silicium avait lieu, conduisant à une microstructure complexe. Afin de limiter les interactions chimiques, des substrats recouverts de silice thermique ont également été utilisées. Les films non dopés présentent des propriétés de luminescence, mise en évidence et discutées en lien avec la microstructure. Pour les films dopés, l’étude structurale a mis en évidence la cristallisation d’une seconde phase de SnO2 de type orthorhombique. Une étude approfondie en STEM-EELS a permis de localiser les ions de terre rare dans la couche. Enfin les propriétés de luminescence des terres rares ont été étudiées en fonction de leur concentration dans le film et de la température de recuit. Après des recuits à 700°C, les couches dopées au Tb émettent intensément dans le vert à température ambiante, ce qui pourrait être intéressant pour le développement de diodes vertes à base de SnO2This thesis concerns the structural characterization and the photoluminescence properties of tin oxide thin films doped with rare earths. The films are doped with cerium, terbium and ytterbium. The films were obtained by evaporation of SnO2 on silicon substrates. The as-deposited films were sub-stoichiometric and the films were then annealed in air at 600°C to reach rutile phase. The microstructural study reveals a substrate oxidation leading to a chemical reaction between tin oxide and silicon, and a complex microstructure. To limit the chemical interaction during annealing, silicon substrate coated with thermal silica were used. Undoped films show a broad luminescent band, which is discussed and linked with the microstructure. On the other hand, the structural study of doped films demonstrated the crystallization of a second phase of SnO2, which is orthorhombic. A STEM-EELS study allow to localize the rare earths ions in the films. Finally, the luminescence properties of the rare earths were study with respect to their concentration and the temperature of annealing. After annealing at 700°C, the Tb-doped films emit intensively in the green region, which might be of interest for the development of SnO2-based green light emitting diodes
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Mustapha, Nazir Mohamad. "Reactive filtered arc evaporation." Thesis, Loughborough University, 1993. https://dspace.lboro.ac.uk/2134/26797.
Повний текст джерелаАнотація:
Conventional physical vapour deposition (PVD) techniques usually result in films of lower quality than the corresponding bulk material. A major problem with PVD films is the presence of columns and voids throughout the thickness of the film. The films may have a low packing density, low micro-hardness and in many cases poor adhesion to the substrate. Many of these problems are a direct consequence of the low energy of the depositing atoms arriving at the substrate during film growth. The resulting film porosity gives rise to a reduction in mechanical strength, and in the case of dielectric optical films, a reduction in the refractive index. The properties of deposited films are greatly improved when the substrate or the growing film is bombarded with more energetic particles. An ideal deposition process requires a high flux of film atoms with an energy of approximately 5-50 eV in order to achieve sufficient surface mobility at the substrate to overcome columnar growth.
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Narayanan, Shankar. "Gas assisted thin-film evaporation from confined spaces." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42780.
Повний текст джерелаАнотація:
A novel cooling mechanism based on evaporation of thin liquid films is presented for thermal management of confined heat sources, such as microprocessor hotspots. The underlying idea involves utilization of thin nanoporous membranes for maintaining microscopically thin liquid films by capillary action, while providing a pathway for the vapor generated due to evaporation at the liquid-vapor interface. The vapor generated by evaporation is continuously removed by using a dry sweeping gas keeping the membrane outlet dry. This thesis presents a detailed theoretical, computational and experimental investigation of the heat and mass transfer mechanisms that result in dissipating heat.
Performance analysis of this cooling mechanism demonstrates heat fluxes over 600W/cm2 for sufficiently thin membrane and film thicknesses (~1-5µm) and by using air jet impingement for advection of vapor from the membrane surface. Based on the results from this performance analysis, a monolithic micro-fluidic device is designed and fabricated incorporating micro and nanoscale features. This MEMS/NEMS device serves multiple functionalities of hotspot simulation, temperature sensing, and evaporative cooling. Subsequent experimental investigations using this microfluidic device demonstrate heat fluxes in excess of 600W/cm2 at 90 C using water as the evaporating coolant.
In order to further enhance the device performance, a comprehensive theoretical and computational analysis of heat and mass transfer at micro and nanoscales is carried out. Since the coolant is confined using a nanoporous membrane, a detailed study of evaporation inside a nanoscale cylindrical pore is performed. The continuum analysis of water confined within a cylindrical nanopore determines the effect of electrostatic interaction and Van der Waals forces in addition to capillarity on the interfacial transport characteristics during evaporation. The detailed analysis demonstrates that the effective thermal resistance offered by the interface is negligible in comparison to the thermal resistance due to the thin film and vapor advection. In order to determine the factors limiting the performance of the MEMS device on a micro-scale, a device-level detailed computational analysis of heat and mass transfer is carried out, which is supported by experimental investigation. Identifying the contribution of various simultaneously occurring cooling mechanisms at different operating conditions, this analysis proposes utilization of hydrophilic membranes for maintaining very thin liquid films and further enhancement in vapor advection at the membrane outlet to achieve higher heat fluxes.
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Au, Daniel Tak Yin. "Evaporation cast thin film carbon nanotube strain gauges." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44860.
Повний текст джерелаАнотація:
This work describes the research performed on synthesising and measuring the gauge factor of evaporation cast thin film carbon nanotube strain gauges. The main characteristics pursued of the strain gauges are inexpensive, easily manufactured and reasonably sensitive. Carbon nanotubes have exhibited a high gauge factor due to their intrinsic piezoresistivity and were incorporated into evaporation cast films to try to take advantage of the high sensitivity. Another direction taken to improve the sensitivity is alignment of carbon nanotubes in the thin film.
Previous work produced an evaporation cast carbon nanotube strain gauge with a relatively high gauge factor. However, it was not reproducible and the research encompassed extends from the previous work. A number of ink compositions with different carbon nanotube and surfactant loadings were used to synthesise thin films of carbon nanotubes on a polyimide substrate. Variations of evaporation casting were used to decrease the evaporation rate in attempts of carbon nanotube alignment through a self-organising liquid crystal phase during evaporation. Other methods of inkjet printing and air flow evaporation casting were also attempted to achieve alignment. Electrical connections using a conductive polymer and metal wires were fabricated onto the samples for electrical measurements. A four-point probe resistance measurement under the application of strain was used to elicit the gauge factors.
The strain gauge design was modified from previous work for more reliable electrical connections and for higher applied strains. A procedure for electrical measurements coupled with the application of strain was devised and the gauge factors achieved varied between 0.1 and 4.0 with a median of 1.1 ±0.1. The median gauge factor was reproducible and exhibited by several samples fabricated with different types of evaporation casting. The decrease in evaporation rate did not result in either alignment or relatively high gauge factors. In general, alignment was not achieved with the other methods of air flow evaporation and inkjet printing.
7
Howell, Aaron W. "Evaporation and disintegration of heated thin liquid sheets." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53861.
Повний текст джерелаАнотація:
In this study, a numerical model is used to investigate the evaporation and flow characteristics of heated liquid sheets and films. The liquid is modeled as water and as black liquor, a byproduct produced by paper mills. In the pulping process, black liquor is concentrated in an evaporator as a falling film. The effectiveness of the evaporator is reduced due to fouling on heat transfer surfaces.
Two flow arrangements are studied: falling films, where the liquor and steam are separated by a heat transfer surface; and liquid curtains, which is a thin sheet of liquid falling due to gravity surrounded by steam. For the liquid curtain, the liquid and gas come into direct contact, therefore there is no place for fouling to occur allowing for a more consistent operation of the evaporator. This type of arrangement is not currently used in paper mills but is being investigated in this work to determine its feasibility.
The fluid system is simulated using the finite volume method with a single-fluid field to capture the liquid-gas interface. This study investigates how the breakup of a liquid curtain is affected by flow parameters and how the breakup into droplets influences the evaporation characteristics of the liquid curtain.
It is found that the falling film evaporator has a much higher liquid evaporation rate than evaporating as a liquid curtain. However the falling film evaporator has an entrance length with no evaporation, and liquid curtains allow for evaporation to start occurring very near the inlet. If reducing length of the evaporator is a priority, liquid curtain evaporators can obtain a higher evaporation rate than falling films within the same distance.
Falling film evaporation has a higher steam efficiency than a liquid curtain evaporator. However, for short evaporator lengths the rate at which water is removed from a liquid curtain evaporator is much greater, but at the cost of a higher steam consumption rate.
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Vaartstra, Geoffrey. "Comprehensive modeling of thin film evaporation in micropillar wicks." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/128335.
Повний текст джерелаАнотація:
Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, June, 2019Cataloged from PDF version of thesis.
Includes bibliographical references (pages 48-50).
In the Information Age, society has become accustomed to continuous, rapid advances in electronics technology. As the power density of these devices increases, heat dissipation threatens to become the limiting factor for growth in the electronics industry. In order to sustain rapid growth, the development of advanced thermal management strategies to efficiently dissipate heat from electronics is imperative. Porous wicks are of great interest in thermal management because they are capable of passively supplying liquid for thin film evaporation, a promising method to reliably dissipate heat in high-performance electronics. While the maximum heat flux that can be reliably sustained (the dryout heat flux) has been well-characterized for many wick configurations, key design information is missing as many previous models cannot determine the distribution of evaporator surface temperature nor temperature at the evaporator's interface with electronic components.
Temperature gradients are inherent to the passive capillary pumping mechanism since the shape of the liquid-vapor interface is a function of the local liquid pressure, causing spatial variation of permeability and the heat transfer coefficient (HTC). Accounting for the variation of the liquid-vapor interface to determine the resulting temperature gradients has been a significant modeling challenge. In this thesis, we present a comprehensive modeling framework for thin film evaporation in micropillar wicks that can predict dryout heat flux and local temperature simultaneously. Our numerical approach captures the effect of varying interfacial curvature across the micropillar evaporator to determine the spatial distributions of temperature and heat flux. Heat transfer and capillary flow in the wick are coupled in a computationally efficient manner via incorporation of parametric studies to relate geometry and interface shape to local permeability and HTC.
While most previous models only consider uniform thermal loads, our model offers the flexibility to consider arbitrary (non-uniform) thermal loads, making it suitable to guide the design of porous wick evaporators for cooling realistic electronic devices. We present case studies from our model that underscore its capability to guide design with respect to temperature and dryout heat flux. This model predicts notable variations of the HTC (-30%) across the micropillar wick, highlighting the significant effects of interfacial curvature that have not been considered previously. We demonstrate the model's capability to simulate non-uniform thermal loads and show that wick configuration with respect to the input thermal distribution has a significant effect on performance due to the distribution of the HTC and capillary pressure. Further, we are able to quantify the tradeoff associated with enhancing either dryout heat flux or the HTC by optimizing geometry.
We offer insights into optimization and further analyze the effects of micropillar geometry on the HTC. Finally, we integrate this model into a fast, compact thermal model (CTM) to make it suitable for thermal/electronics codesign of high-performance devices and demonstrate a thermal simulation of a realistic microprocessor using this CTM. We discuss further uses of our model and describe an experimental platform that could validate our predicted temperature distributions. Lastly, we propose a biporous, area-enhanced wick structure that could push thermal performance to new limits by overcoming the design challenge typically associated with porous wick evaporators.
by Geoffrey Vaartstra.
S.M.
S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Pauken, Michael T. "An experimental investigation of the spreading, durability and maintainability of monolayer films for evaporation suppression from stationary watr pools." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/33624.
Повний текст джерела
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Sait, Hani. "Analytical and experimental study of thin film evaporation in heat pipes /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3164540.
Повний текст джерела
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Johnston, David A. "The use of metal evaporation in the design and manufacture of enzyme electrodes." Thesis, University of the West of Scotland, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323763.
Повний текст джерела
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Back, Markus. "Investigation of the properties of thin films grown via sputtering and resistive thermal evaporation : an Ion Beam Analysis (IBA) study." Thesis, Uppsala universitet, Tillämpad kärnfysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-257506.
Повний текст джерелаАнотація:
In this project, thin films are being manufactured by different methods in a thin film deposition set-up and subsequently characterized. This is done in order to determine if the set-up is capable of producing films of sufficient quality to be used for research purposes in the ion physics group of the division of applied nuclear physics at Uppsala University. Both copper and silver films are manufactured by magnetron sputtering deposition. Copper films are also manufactured by evaporation deposition. Deposition is made on Si(001) substrates. The films are analyzed with Rutherford Backscattering Spectrometry (RBS) and Time of Flight- Elastic Recoil Detection Analysis (ToF-ERDA). Results show that the deposition rate of the set-up is much faster compared to the one provided by the manufacturer of the set-up. The purity of the films i.e. the concentrations of the contaminants are found to be in an acceptable range for research applications with an average oxygen contamination of I det här projektet produceras tunnfilmer med olika metoder i en uppställning för tunnfilmsdeposition och karaktäriseras sedan för att bedöma om maskinen är kapabel att producera filmer av tillräckligt bra kvalitet för att kunna användas i forskningssyften inom jonfysikgruppen på avdelningen för tillämpad kärnfysik på Uppsala Universitet. Både koppar och silverfilmer produceras med magnetronsputtring. Kopparfilmer produceras också med resistiv förångning. Deposition sker på Si(001)-substrat. Filmerna analyseras med Rutherford Backscattering Spectrometry (RBS) och Time of Flight- Elastic Recoil Detection Analysis (ToF-ERDA). Resultaten visar att depositionshastigheten för maskinen är snabbare än det som angetts av företaget som producerar maskinen. Renheten hos filmerna, dvs. koncentrationen av föroreningar, finnes vara inom en acceptabel nivå för forskningstillämpningar med en genomsnittlig syrekontamination på
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Yeh, Jen-Yu. "Electron-beam biased reactive evaporation of silicon, silicon oxides, and silicon nitrides /." Online version of thesis, 1991. http://hdl.handle.net/1850/11106.
Повний текст джерела
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Jiao, Anjun. "Modeling of thin film evaporation heat transfer and experimental investigation of miniature heat pipes." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5613.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--University of Missouri-Columbia, 2008.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on June 8, 2009) Vita. Includes bibliographical references.
15
Gupta, Shikha S. B. Massachusetts Institute of Technology. "Fabrication of In₂(Se, Te)₃ chalcogenide thin films by thermal co-evaporation." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/114087.
Повний текст джерелаАнотація:
Thesis: S.B., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2001.Cataloged from PDF version of thesis. "May 2001."
Includes bibliographical references (pages 46-47).
In₂(Se, Te)₃ III-VI chalcogenides belong to a unique class of phase change materials that have interesting optical and electrical properties, making them suitable for a wide variety of applications, including absorbers for solar cells and storage materials in memory devices. A greater understanding of how different growth parameters influence the crystallinity and microstructure of such chalcogenide thin films can lead to an enhanced ability to manipulate the materials for desired optoelectrical characteristics. The purpose of the following thesis was threefold. The first was to fabricate homogeneous, single-phase thin films of In2(Se, Te)₃ using thermal co-evaporation of elemental In and (Se, Te) in a high vacuum vapor deposition chamber. The In₂(Se, Te)₃ samples prepared by this method were found to be single phase textured films. Since re-evaporation of (Se, Te) from the films has previously resulted in deviations from the stoichiometric In₂(Se, Te)₃ compound [1], the second element of this thesis involved the microstructural characterization of films deposited with an excess of (Se, Te). The results from XRD and AFM reveal that after annealing the films the excess material does not manifest itself in any observable manner. Preliminary results from RBS and EDS reveal that some of the excess material may actually be evaporating through the 50 Å A1₂O₃ capping layer deposited on the film's surface, though further analysis with Auger and XPS will be necessary to enhance the understanding of what happens to the excess material. The third element was to assess how temperature and duration of post deposition thermal treatment influenced the crystal structure and surface morphology of the films. The films were annealed at temperatures ranging from 473 to 673K for 5 minutes, 1 hour, and 4 hours. Results from XRD showed that vacuum annealing of the samples at temperatures above 623K for times above 1 hour consistently produced well-oriented thin films of high crystalline quality. Higher annealing temperature resulted in films with higher crystallinity, whereas annealing durations longer than 1 hour did not contribute significantly to the film phase or crystallinity. AFM measurements of surface morphology before and after annealing showed that the roughness of the films before annealing was on the order of a few angstroms, whereas large, distinct grains and surface inhomogeneites were present on the sample surface after annealing. Again, no observable change was reported for films with excess (Se, Te) indicating that the single-phase compound that formed was very stable.
by Shikha Gupta.
S.B.
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Souche, Mireille, and Didier Long. "Ultra fast processes for solvent evaporation in thin polymer films below Tg." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-195014.
Повний текст джерела
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Souche, Mireille, and Didier Long. "Ultra fast processes for solvent evaporation in thin polymer films below Tg." Diffusion fundamentals 3 (2005) 36, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14326.
Повний текст джерела
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Wolf, Michael Photovoltaics & Renewable Energy Engineering Faculty of Engineering UNSW. "Upgrading and commissioning of a high vacuum deposition system for the evaporation of silicon thin-film solar cells." Publisher:University of New South Wales. Photovoltaics & Renewable Energy Engineering, 2009. http://handle.unsw.edu.au/1959.4/43725.
Повний текст джерелаАнотація:
Using electron beam evaporation for the production of polycrystalline silicon (pc-Si) thin-film solar cells is an attractive alternative to PECVD deposition. Due to its faster deposition rate, using evaporation technology could significantly reduce module production costs. Other advantages are lower running costs, and the fact that no toxic gases are involved. However, currently no on-shelf equipment is available, and research in this field often relies on in-house designed systems. These can have various problems with reliability, deposition uniformity, and due to their custom design require frequent maintenance. In this work, a newly purchased electron beam evaporation system was upgraded and redesigned to be capable of depositing amorphous Si diodes for the fabrication of pc-Si thin-film solar cells. The main goal of the upgrade was to provide a safe and reliable tool which allows for the deposition of high purity semiconductor material. Reliable and safe operation was accomplished by designing the entire electrical supply circuit and incorporating various safety interlocks. Source cross-contamination issues were addressed by installing a specially designed shroud (source housing). To provide uniform substrate temperatures up to 600??C, a heater was specially designed, fabricated, installed and tested. Accurate design of all mechanical system components was realised by using 3D product design software (ProEngineer). The new evaporator was commissioned, which included testing and calibration of all the system components required for depositing on substrate sizes of up to 10x10cm2. Over this area a Si film thickness uniformity of +/-2%, performed with a maximum deposition rate of 7nm/s was achieved. Initial experiments using solid phase crystallisation and rapid thermal annealing revealed a sheet resistance uniformity of +/-4% for the Phosphorus and +/-7% for the Boron dopant effusion cell. Experimentation via Raman spectrometry and X-ray diffraction has revealed good crystalline properties, of the crystallised Si films, which is comparable to those of existing evaporation systems. Although the system was upgraded to achieve deposition pressures below 3x10-7 mbar, experiments have shown that this quality of vacuum may not be necessary for the fabrication of low impurity films. The system is now ready for further research in the field of thin-film photovoltaics, and the first functioning devices have been fabricated.
19
Vemuri, Prasanna. "Synthesis of cubic boron nitride thin films on silicon substrate using electron beam evaporation." Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc5542/.
Повний текст джерелаАнотація:
Cubic boron nitride (cBN) synthesis has gained lot of interest during the past decade as it offers outstanding physical and chemical properties like high hardness, high wear resistance, and chemical inertness. Despite of their excellent properties, every application of cBN is hindered by high compressive stresses and poor adhesion. The cost of equipment is also high in almost all the techniques used so far. This thesis deals with the synthesis of cubic phase of boron nitride on Si (100) wafers using electron beam evaporator, a low cost equipment that is capable of depositing films with reduced stresses. Using this process, need of ion beam employed in ion beam assisted processes can be eliminated thus reducing the surface damage and enhancing the film adhesion. Four sets of samples have been deposited by varying substrate temperature and the deposition time. scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) techniques have been used to determine the structure and composition of the films deposited. X-ray diffraction (XRD) was performed on one of the samples to determine the thickness of the film deposited for the given deposition rate. Several samples showed dendrites being formed as a stage of film formation. It was found that deposition at substrate temperature of 400oC and for a period of one hour yielded high quality cubic boron nitride films.
20
Wee, Sang-Kwon. "Microscale observables for heat and mass transport in sub-micron scale evaporating thin film." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/312.
Повний текст джерелаАнотація:
A mathematical model is developed to describe the micro/nano-scale fluid flow and heat/mass transfer phenomena in an evaporating extended meniscus, focusing on the transition film region under nonisothermal interfacial conditions. The model incorporates thermocapillary stresses at the liquid-vapor interface, a slip boundary condition on the solid wall, polarity contributions to the working fluid field, and binary mixture evaporation. The analytical results show that the adsorbed film thickness and the thin film length decrease with increasing superheat by the thermocapillary stresses, which influences detrimentally the evaporation process by degrading the wettability of the evaporating liquid film. In contrast, the slip effect and the binary mixture enhance the stability of thin film evaporation. The slip effect at the wall makes the liquid in the transition region flow with smaller flow resistance and thus the length of the transition region increases. In addition, the total evaporative heat flow rate increases due to the slip boundary condition. The mixture of pentane and decane increases the length of the thin film by counteracting the thermocapillary stress, which enhances the stability of the thin film evaporation. The polarity effect of water significantly elongates the thin film length due to the strong adhesion force of intermolecular interaction. The strong interaction force restrains the liquid from evaporation for a polar liquid compared to a non-polar liquid. In the experimental part, laser induced fluorescence (LIF) thermometry has been used to measure the microscale temperature field of a heated capillary tube with a 1 mm by 1 mm square cross section. For the temperature measurement, the calibration curve between the temperature and the fluorescent intensity ratio of Rhodamine-B and Rhodamine-110 has been successfully obtained. The fluorescent intensity ratio provides microscale spatial resolution and good temperature dependency without any possible bias error caused by illuminating light and background noise usually encountered in conventional LIF techniques. For the validation of the calibration curve obtained, thermally stratified fields established inside a glass cuvette of 10 mm width were measured. The measurement result showed a good agreement with the linear prediction. The temperature measurement in a 1 mm capillary tube could provide the feasible method of temperature measurement for the thin film region in the future.
21
Sun, Wei. "EVAPORATION-INDUCED FORMATION OF WELL-ORDERED SURFACE PATTERNS ON POLYMER FILMS." UKnowledge, 2015. http://uknowledge.uky.edu/cme_etds/54.
Повний текст джерелаАнотація:
Various techniques of fabricating surface patterns of small scales have been widely studied due to the potential applications of surface patterns in a variety of areas. It is a challenge to fabricate well-ordered surface area efficiently and economically. Evaporation-induced surface patterning is a promising approach to fabricate well-ordered surface patterns over a large area at low cost. In this study, the evaporation-induced surface patterns with controllable geometrical characteristics have been constructed. The dewetting kinetics on deformable substrate is also investigated.
Using simple templates to control the geometry and the evaporation behavior of a droplet of volatile solvent, various gradient surface patterns, such as concentric rings, multiple straight stripes formed with a straight copper wire, etc. have been constructed on PMMA films. The wavelength and amplitude are found to decreases with the decrease of the distance to the objects used in templates. There is also a nearly linear relation between the amplitude and wavelength. The effects of several experimental parameters on the geometrical characteristics of the surface structures are studied, i.e. dimensions of the template, film thickness (solution concentration), substrate temperature, etc. The wavelength and amplitude increase with the increase of the film thickness (solution concentration), with the increase of the dimension of the template. However with the increase of the substrate temperature, the wavelength increases, while the amplitude decrease. Hexagonal network in pre-cast PMMA film have been fabricated by a “breath figure” approach at low humidity and low substrate temperature. The dimensions of the hexagonal holes are dependent on the template size and film thickness.
The kinetics of the evaporative dewetting of a liquid (toluene) film on a deformable substrate (PMMA film) with the confinement of a circular copper ring is also studied. The liquid film first dewets from the outside towards the copper ring. When a critical volume is reached, an internal contact line appears, which dewets from the center to the copper ring smoothly with a constant velocity, then switches to a “stick-slip” motion. The average velocity of the smooth motion increases with the increase of the copper ring size and film thickness.
22
Lu, Zhengmao. "Design and modeling of a high flux cooling device based on thin film evaporation from thin nanoporous membranes." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93824.
Повний текст джерелаАнотація:
Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 44-46).
Heat dissipation is a limiting factor in the performance of integrated circuits, power electronics and laser diodes. State-of-the-art solutions typically use air-cooled heat sinks, which have limited performance owing to the use of air. One of the promising approaches to address these thermal management needs is liquid vapor phase-change. In this thesis, we present a study into the design and modeling of a cooling device based on thin film evaporation from a nanoporous membrane supported on microchannels. The concept utilizes the capillary pressure generated by the small pores to drive the liquid flow and largely reduces the viscous loss due to the thinness of the membrane. The interfacial transport has been re-investigated where we use the moment method to solve the Boltzmann Transport Equation. The pore-level transport has been modeled coupling liquid transport, vapor transport and the interfacial balance. The interfacial transport inside the pore also serves as a boundary condition for the device-level model. The heat transfer and pressure drop performance have been modeled and design guidelines are provided for the membrane-based cooling system. The optimized cooling device is able to dissipate 1 kW/cm² heat flux with a temperature rise less than 30 K from the vapor side. Future work will focus on more fundamental understanding of the mass and energy accommodation at the liquid vapor interface.
by Zhengmao Lu.
S.M.
23
Hus, Saban Mustafa. "Physical Properties Of Cdse Thin Films Produced By Thermal Evaporation And E-beam Techniques." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607608/index.pdf.
Повний текст джерелаАнотація:
CdSe thin films were deposited by thermal evaporation and e-beam
evaporation techniques on to well cleaned glass substrates. Low dose of boron have
been implanted on a group of samples. EDAX and X-ray patterns revealed that
almost stoichiometric polycrystalline films have been deposited in (002) preferred
orientation. An analysis of optical measurements revealed a sharp increase in
absorption coefficient below 700 nm and existence of a direct allowed transition. The
calculated band gap was around 1.7 eV. The room temperature conductivity values
of the samples were found to be between 9.4 and 7.5x10-4 (Ω
-cm)-1 and 1.6x10-6 and 5.7x10-7 (&
#937
-cm)-1for the thermally evaporated and e-beam evaporated samples respectively. After B implantation conductivity of these films increased 5 and 8 times respectively. Hall mobility measurements could be performed only on the thermally evaporated and B-implanted e-beam evaporated samples and found to be between 8.8 and 86.8 (cm2/V.s). The dominant conduction mechanism were determined to be thermionic emission above 250 K for all samples. Tunneling and v variable range hopping mechanisms have been observed between 150-240 K and 80- 140 K respectively. Photoconductivity &
#8211
illumination intensity plots indicated two recombination centers dominating at the low and high regions of studied temperature range of 80-400 K. Photoresponse measurements have corrected optical band gap measurements by giving peak value at 1.72 eV.
24
Tan, Qin [Verfasser]. "Influence of vacuum-assisted solvent evaporation on MAPbI3 layers and solar cells / Qin Tan." Berlin : Freie Universität Berlin, 2019. http://d-nb.info/1198862548/34.
Повний текст джерела
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RIBEIRO, MONICA CRISTINA RICCIO. "THERMODYNAMIC MODELLING OF CDTE THIN FILM DEPOSITION BY ELEMENTAL CO-EVAPORATION, UNDER ISOTHERMAL TRANSPORT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7072@1.
Повний текст джерелаАнотація:
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOO objetivo do presente trabalho é a deposição de filmes de telureto de cádmio a partir de duas fontes de materiais, Cd e Te, com base no uso de diagramas de potenciais termodinâmicos para avaliar as condições de deposição. Em especial, o método proposto permite avaliar a influência de contaminantes gasosos, tais como, oxigênio, sobre as fases condensadas. O método também pode ser aplicado para a deposição de outros compostos que sejam mais estáveis que os elementos que os compõem. O processamento utilizado na deposição utiliza uma técnica alternativa onde as temperaturas de fonte e de substrato são as mesmas.
The objective of the present work is deposition of Cadmiun Telurides films from two sources of materials, Cd and Te, on the basis of the use of diagrams of thermodynamic potentials to evaluate the deposition conditions. In special, the considered method allows to evaluate the influence of gaseous contaminantes, such as, oxygen, on the condensed phases. The method can be applied for the deposition of other compounds that are more stable than the constituent elements. The equipment used in the deposition uses an alternative technique where the temperatures of source and substrate are the same ones.
26
Steward, Ian. "Photoconductivity Spectroscopy of Deep Level Defects of ZnO Thin Films Grown by Thermal Evaporation." Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1283472110.
Повний текст джерела
27
Sosnowski, Pawel. "Numerical investigation of evaporation and condensation of thin films in conjugated heat transfer systems." Doctoral thesis, Università degli studi di Trieste, 2013. http://hdl.handle.net/10077/8662.
Повний текст джерелаАнотація:
2011/2012Evaporation and condensation of thin liquid films on solid surfaces are common elements of industrial processes. In many cases they have a significant impact on the physics of the studied case. At the same time, experimental studies can prove to be troublesome, mostly because of the amount of possible setups, complex geometries of interest, numerous materials being used and cost. For that reason it is reasonable to study this phenomena using numerical methods. Having the advantage in speed and cost of performance, computational studies become a valuable tool. For evaporation and condensation process, one has to deal with buoyancy driven fluid flows, conjugated heat transfer between gaseous and solid phases, film thickness modeling, vapor phase behavior, and phase transition of the thin fluid film into vapor phase. The strong conjunction and mutual interaction of mentioned effects is the main focus of presented work. The gas phase behavior is being calculated using incompressible Navier-Stokes equations under Boussinesq approximation. The solutions of the partial differential equations are obtained with numerical methods using Eulerian finite volume discretization (Kundu and Cohen [2002]). Time advancement is being treated with second order implicit discretization. For cases with high Reynolds number, large eddy simulation (LES) techniques are used. Due to the complexity of the geometries of interest a dynamic computation of the Smagorinsky constant is preferred, applying the lagrangian dynamic model proposed by Meneveau et al. [1996]. The liquid film present on the surface of the solids is modeled following Petronio[2010]. Since the film is thin, it is assumed that it can be represented only by its thickness. This also leads to assumption that the heat transfer through the film is instantaneous. The vapor is represented by concentration of this phase in the volume of gas. The concentration is transported by convection and diffusion. The phenomena of evaporation and condensation of the thin films are driven by the presence of concentration gradients next to the surfaces. Phase transition of vapor to fluid, or other way around, acts on the energy balance, id. est latent heat is released into the gas when condensation occurs or the solid is cooled during evaporation. The heat transport is modeled in both solid and fluid domains. The case is split into separate regions with different material properties. These regions are solved one by one in a serial way using numerical techniques consistent with domain decomposition methods described by Quarteroni and Valli [1999]. The energy transport among the regions is performed by applying a heat coupling boundary conditions. The main focus of this work is to provide a reliable model for simulation system with complex physics involving fluid motion, heat transport in multi region domains (fluid-solid), vapor transport, thin film evolution and evaporation and condensation effects on energy balance. Proposed model is validated on simple geometries and later applied to problem of evaporation in vertical channel flow. The reference to the channel case is work of Laaroussi et at. [2009]. Presented study aims in providing comprehensive insights into physical effects that appear when the solid wall is being directly modeled and when latent heat transformations are taken into account. The final test is performed on a vertical channel with forced turbulent flow, directly modeled solid walls and evaporation or condensation happening on the boundary. Having the model working within such complex frame allows for its future usage in elaborate industrial applications.
XXV Ciclo
1985
28
Karaagac, Hakan. "Electrical, Structural And Optical Properties Of Aggase2-xsx Thin Films Grown By Sintered Powder." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612362/index.pdf.
Повний текст джерелаАнотація:
In the present study, the effect of S and Se substitution on structural, electrical and optical properties of AgGa(Se2-xSx) thin films has been investigated.
AgGa(Se0.5S0.5 )2 thin films were prepared by using the thermal evaporation method. X-ray diffraction (XRD) analysis has revealed that the transformation from amorphous to polycrystalline structure took place at about 450 oC. The detailed information about the stoichometry and the segregation mechanisms of the constituent elements in the structure has been obtained by performing both energy dispersive X-ray analysis (EDXA) and X-ray photoelectron spectroscopy (XPS) measurements.
AgGaSe2 thin films were deposited by using both electron-beam (e-beam) and sputtering techniques. In e-beam evaporated thin films, the effect of annealing on the structural and morphological properties of the deposited films has been studied by means of XRD, XPS, scanning electron microscopy (SEM) and EDXA measurements. Structural analysis has shown that samples annealed between 300 and 600 oC were in polycrystalline structure with co-existance of Ag, Ga2Se3, GaSe, and AgGaSe2. The variation of surface morphology, chemical composition and bonding nature of constituent elements on post-annealing has been determined by EDXA and XPS analyses.
AgGaSe2 thin films were also prepared by using sputtering technique. XRD measurements have shown that the mono-phase AgGaSe2 structure is formed at annealing temperature of 600 oC. The crystal-field and spin-orbit splitting levels were resolved. These levels around 2.03 and 2.30 eV were also detected from the photospectral response measurements.
Thin films of Ag-Ga-S (AGS) compound were prepared by using AgGaS2 single crystalline powder and deposition of the excess silver (Ag) intralayer with double source thermal evaporation method. As a consequence of systematic optimization of thickness of Ag layer, Ag(Ga,S) with the stoichiometry of AgGa5S8 and AgGaS2 were obtained and systematic study to obtain structural, electrical and optical properties was carried out.
29
GUERREIRO, SERGIO S. "Estudo e caracterizacao de filmes finos de nitreto de titanio obtidos por evaporacao a arco catodico de deposicao a vacuo." reponame:Repositório Institucional do IPEN, 1994. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10377.
Повний текст джерелаАнотація:
Made available in DSpace on 2014-10-09T12:37:59Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:05:53Z (GMT). No. of bitstreams: 1 05586.pdf: 7089535 bytes, checksum: 4459c81f8f267c76f9328265ae1fc952 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
30
Stewart, Brian K. "Development of a Thin-Film Evaporative Cooling System for a High Energy Thulium Holmium: Lutetium Lithium Flouride Solid-State Laser Oscillator Crystal." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/6973.
Повний текст джерелаАнотація:
The feasibility and critical design parameters for the development of a thin-film evaporative cooling concept for a high energy, pulsed solid-state laser oscillator were investigated. The scope of the investigation was broad, and a multidisciplinary approach was employed. No contra-indicators for the feasibility of the proposed system were revealed.
A 1-dimensional two-fluid was developed to model the hydrodynamic flow and heat transfer assuming a constant wall heat flux. This analysis produced nominal pressure drops for the flow required, indicating nominal power will be required to transport fluid across the crystal surface.
Interfacial experiments reveal that the laser crystal material has a surface energy of approximately 30 mN/m, and is highly dispersive in nature.
Design rules to allow for the orthotropic thermal expansion of the crystal rod surrounded by a thin metal sleeve were developed to support the design of a hermetic crystal-metal seal. The results indicate that commercially pure nickel produces minimal joint stresses for large thermal excursions.
31
Ganapathy, Subramanian Santhana. "Bi-Sr-Ca-Cu-O thin films grown by flash evaporation and pulsed laser deposition." Texas A&M University, 2003. http://hdl.handle.net/1969.1/47.
Повний текст джерелаАнотація:
Bismuth-Strontium-Calcium-Copper-Oxide (BSCCO) compounds are an important family of compounds that have one of the highest transition temperatures among all high-temperature superconductors. The compound is known to exist in three distinct phases, commonly referred to as the 2201, 2212 and 2223 phases. Of these three phases, the 2212 and 2223 phases are the most important, as their transition temperature is higher than the boiling point of liquid nitrogen. It is desirable to produce the compound in thin film form, as the bulk samples are normally polycrystalline.
This thesis compares thin films produced by two techniques for depositing BSCCO in order to understand the effect of various processing parameters on the final quality of the thin films. Thin films were grown by flash evaporation at Texas A&M University, and by pulsed laser deposition (PLD) at the University of Wollongong, Australia. The latter of these techniques is widely used for growing thin films of various compounds. Single-phase 2212 films were grown on a MgO substrate using the pulsed laser deposition technique from commercially available 2212 powder. The effect of annealing on the thin films was also studied.
32
Adera, Solomon (Solomon E. ). "Thin-film evaporation from well-defined silicon micropillar wicks for high-heat-flux thermal management." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/110888.
Повний текст джерелаАнотація:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 129-133).
The generation of concentrated heat loads in advanced microprocessors, power amplifiers, and concentrated photovoltaics present significant thermal management challenge for defense, space and commercial applications. Liquid to vapor phase-change strategies are promising due to the high latent heat of vaporization of the working fluid. In particular, capillary pumped thin-film evaporation from micropillar wicks has received significant attention owing to advances in micro/nano-fabrication and the potential to dissipate high heat fluxes by increasing the evaporative area. Yet, predictive tools to design various wicking structures are not available due to limited understanding of the thermal-fluidic transport. This thesis reports experimental characterization and modeling of capillary-limited thin-film evaporation from micropillar wicks. We fabricated test devices and experimentally characterized the thermal performance of well-defined silicon micropillar wicks. The experiments were designed to investigate the capillary-limited dryout heat flux by ensuring pure thin-film evaporation in the absence of nucleate boiling. The tests were performed in a temperature controlled saturated vapor environment to accurately control the operating conditions. We also developed a unified semi-analytical thermal-fluidic model that incorporates the capillary pressure, permeability, and thermal resistance to help explain the experimental results. We then extended this work to study capillary-limited thin-film evaporation for dissipating extreme heat fluxes. We experimentally dissipated =6 kW/cm2 from a 640x620 [mu]m2 footprint, the largest heat flux reported to date when compared to past thin-film evaporation studies with similar size hotspots. We also demonstrated the potential of our devices to cool concurrent hotspots as well as when moderate uniform background heat flux was superposed with a hotspot. Our thermal management strategy is self-regulating and provides on-demand cooling unlike existing thermal management solutions. To gain insight into the fundamental physics of fluidic and thermal transport within the micropillar wick and explain the ultra-high heat fluxes demonstrated in our experiments, we developed a semi-analytical thermal-fluidic model that can predict the capillary-limited dryout heat flux via thin-film evaporation. The model compares well with our experiments. The results of this investigation will assist to better understand the fluidic and thermal transport of thin liquid films in microstructured wicks during thin-film evaporation. These studies suggest that capillary-pumped thin-film evaporation is a promising thermal management strategy for the next generation of high performance electronics. The insights gained from this thesis can be used as guidelines to improve the design and optimize the heat transfer performance of wicking structures which are commonly used in phase-change based thermal management devices such as heat pipes, vapor chambers, and other closed-loop configurations.
by Solomon Adera.
Ph. D.
33
Candan, Idris. "Growth And Characterization Of Cuin1-x Gaxse2 (cigs) Thin Films For Solar Cell Structures." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611305/index.pdf.
Повний текст джерелаАнотація:
Direct conversion of solar energy, which is the most powerful and unlimited one among the renewable energy sourcesinto the electrical energy by the photovoltaic devices, is a promising way of meeting the energy needs of future. Thin film semiconductor materials show great promise for the production of efficient, low-cost solar cell devices. Recently advanced research on thin film photovoltaics in all aspects, has attracted intense attention. Thin film semiconductors for the photovoltaic applications are deposited in large areas by different methods. In this study, deposition and characterization of CuIn1-x GaxSe2 ( CIGS ) semiconductor thin films by thermal evaporation and e-beam evaporation methods were investigated. Material properties and deposition parameters of the thin films are aimed to be optimized for solar cell applications. Structural properties of the deposited CIGS thin films were examined through X-ray diffraction and Energy Dispersive X-ray Analysis. The temperature dependent electrical conductivity, Hall effect and photoconductivity of these samples have been measured between 100 and 400 K. For the optical characterization of CIGS thin films, the transmission measurements have been carried out in the wavelength region of 325-900 nm. The changes in the structural, electrical and optical properties of samples through post-depositional annealing effect were also analyzed.
34
Todorova, Desislava V. "Modelling of dynamical effects related to the wettability and capillarity of simple and complex liquids." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13740.
Повний текст джерелаАнотація:
This Thesis explores physical phenomena characteristic for thin liquid films and small droplets of simple and complex liquids on solid substrates for which wettability and capillarity control their statical and dynamical properties. We start by discussing the general concepts of wettability and capillarity and introduce the common mathematical framework of the lubrication approximation for studies of thin liquid films and small contact angle drops. We demonstrate the derivation of the generic equation describing the evolution of a film of simple liquid from the Navier-Stokes equations. We show how this model can be further extended to incorporate various effects relevant to the case of complex liquids. The results described in the Thesis comprise three projects with the common main theme of the influence of wettability and capillarity on the statics and dynamics of the studied systems, namely (i) Evaporating sessile droplets fed through the solid substrate - a geometry that allows us to discuss steady states of the system and their role in the time evolution of freely evaporating droplets without influx in an isothermal case; (ii) The influence of a solute--dependent wettability on the stability, static and dynamical properties of thin films and drops of non-volatile mixtures, suspensions and solutions; (iii) A parameter-passing scheme between particle-based Molecular Dynamics simulations and the continuum lubrication model which allows us to discuss equilibrium properties of small polymeric droplets. We present the physical questions arising in the three systems and discuss approaches and results as well as possible extensions.
35
Yilmaz, Koray. "Investigation Of Inse Thin Film Based Devices." Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12605431/index.pdf.
Повний текст джерелаАнотація:
In this study, InSe and CdS thin films were deposited by thermal evaporation method onto glass substrates. Schottky and heterojunction devices were fabricated by deposition of InSe and CdS thin films onto SnO2 coated glass substrates with various top metal contacts such as Ag, Au, In, Al and C. The structural, electrical and optical properties of the films were investigated prior to characterization of the fabricated devices.
The structural properties of the deposited InSe and CdS thin films were examined through SEM and EDXA analysis. XRD and electrical measurements have indicated that undoped InSe thin films deposited on cold substrates were amorphous with p-type conductivity lying in the range of 10-4-10-5 (
.cm)-1 at room temperature. Cd doping and post-depositional annealing effect on the samples were investigated and it was observed that annealing at 100 oC did not show any significant effect on the film properties, whereas the conductivity of the samples increased as the Cd content increases. Temperature dependent I-V and Hall effect measurements have shown that conductivity and carrier concentration increases with increasing absolute temperature while mobility is almost temperature independent in the studied temperature range of 100-430 K. The structural and electrical analysis on the as-grown CdS thin films have shown that the films were polycrystalline with n-type conductivity. Temperature dependent conductivity and Hall effect measurements have indicated that conductivity, mobility and carrier concentrations increases with increasing temperature. Transmission measurements on the as-grown InSe and CdS films revealed optical band gaps around 1.74 and 2.36 eV, respectively. Schottky diode structures in the form of TO/p-InSe/Metal were fabricated with a contact area of around 8x10-3 cm2 and characterized. The best rectifying devices obtained with Ag contacts while diodes with Au contacts have shown slight rectification. The ideality factor and barrier height of the best rectifying structure were determined to be 2.0 and 0.7 eV, respectively. Illuminated I-V measurements revealed open-circuit voltages around 300 mV with short circuit current 3.2x10-7 A. High series resistance effect was observed for the structure which was found to be around 588 &
#61527
. Validity of SCLC mechanism for Schottky structures was also investigated and it was found that the mechanism was related with the bulk of InSe itself. Heterostructures were obtained in the form of TO/n-CdS/p-InSe/Metal and the devices with Au and C contacts have shown the best photovoltaic response with open circuit voltage around 400 mV and short circuit current 4.9x10-8 A. The ideality factor of the cells was found to be around 2.5. High series resistance effect was also observed for the heterojunction devices and the fill factors were determined to be around 0.4 which explains low efficiencies observed for the devices.
36
Sedani, Salar Habibpur. "Fabrication And Doping Of Thin Crystalline Si Films Prepared By E-beam Evaporation On Glass Substrate." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615628/index.pdf.
Повний текст джерелаАнотація:
In this thesis study, fabrication and doping of silicon thin films prepared by electron beam evaporation equipped with effusion cells for solar cell applications have been investigated. Thin film amorphous Si (a-Si) layers have been fabricated by the electron beam evaporator and simultaneously doped with boron (B) and phosphorous (P) using effusion cells. Samples were prepared on glass substrates for the future solar cell operations. Following the deposition of a-Si thin film, crystallization of the films has been carried out. Solid Phase Crystallization (SPC) and Metal Induced Crystallization (MIC) have been employed to obtain thin film crystalline Si. Crystallization was performed in a conventional tube furnaces and Rapid Thermal annealing systems (RTA) as a function of process parameters such as annealing temperature and duration. Produced films have been characterized using chemical and structural characterization techniques such as Raman Spectroscopy, X-Ray Diffractometer and Secondary Ion Mass Spectrometer (SIMS). The electrical properties of the films have been studied using Hall Effect and I-V measurements as a function of doping.
We have demonstrated successful crystallization of a-Si by SPC at temperatures above 600 °C. The crystallization occurred at lower temperatures in the case of MIC. For doping, P was evaporated from the effusion cell at a temperature between 600 °
C and 800 °
C. For B, the evaporation temperature was 1700 °
C and 1900 °
C. The thickness and the band gap of the Si films were determined by ellipsometry method and the results were compared for different evaporation temperatures. The effect of doping was monitored by the I-V and Hall Effect measurements. We have seen that the doping was accomplished in most of the cases. For the samples annealed at relatively high temperatures, the measured doping type was inconsistent with the expected results. This was attributed to the contamination from the glass substrate. To understand the origin of this contamination, we analyzed the chemical structure of the film and glass by X-ray Fluorescence (XRF) and seen that the glass is the main source of contamination. In order to prevent this contamination we have suggested covering the glass substrate with Si3N4 (Silicon Nitride) which act as a good diffusion barrier for impurities.
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Lucy, Irine Banu. "Electrical and optical properties of Cu-GeOâ†2 thin solid films prepared by vacuum co-evaporation." Thesis, Brunel University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320860.
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Hassan, Aseel Kadhim. "Studies in electronic conduction processes in organic semiconducting thin films of copper phthalocyanine prepared by evaporation." Thesis, Keele University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306847.
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DI, MARE Simone. "Tin sulphide solar cells by thermal evaporation." Doctoral thesis, 2017. http://hdl.handle.net/11562/961461.
Повний текст джерелаАнотація:
Produrre energia elettrica dalla combustione di carburanti di origine fossile o dalla fissione di materiale radioattivo significa inquinare il pianeta, impoverirlo delle sue risorse e non garantire un futuro alle generazioni future. Sebbene nei suoi report annuali l’agenzia internazionale per l’energia (IEA) dipinga una situazione di espansione della produzione di energia “verde”, il crescente fabbisogno di energia pulita e a basso costo spinge la ricerca verso nuove frontiere. Nel panorama del fotovoltaico, di anno in anno si vedono maturare i frutti della ricerca negli annunci di nuovi record mondiali di efficienza per molte tecnologie: nuove tecnologie emergenti, basate su concetti o materiali innovativi, si stanno aggiungendo a tecnologie mature, quali quelle basate su Si, CdTe o CuInxGa(1-x)Se2. Un esempio di queste nuove tecnologie sono quelle basate sui semiconduttori composti totalmente da elementi chimici non tossici ed abbondanti nella crosta terrestre (quindi potenzialmente a basso costo), come Cu2ZnSnS4 o SnS. In questa tesi di dottorato, verranno studiati alcuni aspetti del solfuro di stagno, SnS, in vista di una sua possibile applicazione come strato assorbente per celle solari a film sottile. Il solfuro di stagno ha ottime proprietà optoelettroniche (band gap diretta nella regione di massima efficienza teorica, ottimo coefficiente di assorbimento della luce, e mostra intrinsecamente conduzione di tipo p), che lo rendono un ottimo candidato per il fotovoltaico del futuro. In questa tesi, verranno dapprima discusse le difficoltà incontrate con l’apparato di deposizione e come sono state superate. Successivamente verrà descritto e analizzato il dispositivo solare basato sul solfuro di stagno e caratterizzato dalla migliore prestazione: questo risultato è in linea con quanto pubblicato in letteratura. La difficoltà nel riprodurre questo risultato in modo sistematico ci spingerà poi ad indagarne le possibili cause: suggeriremo la presenza di una possibile correlazione tra la performance dei nostri dispositivi e la storia termica del materiale grezzo utilizzato per evaporare lo strato assorbente. Nel proseguo della tesi, dato che anche il miglior risultato ha comunque mostrato una performance lontana dal limite teorico per un materiale con la band gap dell’SnS, studieremo gli effetti di alcuni trattamenti post deposizione ideati per migliorare le caratteristiche optoelettroniche attraverso il miglioramento della qualità cristallina dell’assorbitore. Tali trattamenti post deposizione sono fondamentali in altre tecnologie, come nel caso del CdTe. Si studieranno due tipologie di trattamento termico: in atmosfera controllata o in aria, utilizzando vari composti a base di cloro e non, atti a favorire la ricristallizzazione dell’assorbitore. I risultati ottenuti verranno discussi caso per caso. Infine, anziché concentrarci ancora sulle caratteristiche dell’assorbitore stesso, ma sempre con lo scopo finale di migliorare le prestazioni dei nostri dispositivi, investigheremo delle alternative per gli altri strati che costituiscono nel loro insieme la cella solare: il contatto elettrico anteriore, quello posteriore, e infine il materiale semiconduttore di tipo n che completa la giunzione p-n.The production of electricity by the combustion of fossil fuels or by the fission of radioactive materials leads to the pollution of Earth’s environment, impoverishes Earth of its resources and does not secure the future for generations to come. Although International Energy Agency (IEA) in its annual reports depicts an increase of electricity production from renewable energy sources, the increasing need for low cost clean energy pushes research towards new frontiers. In photovoltaics, year after year, we see research coming to fruition with the announcements of new world record efficiencies for many technologies: new emerging technologies, based on innovative concepts or materials, are added to the mature ones, such as those based on Si, CdTe o CuInxGa(1-x)Se2. Examples of these innovations are those based on semiconductor compounds totally constituted by non-toxic and Earth’s crust abundant chemical species (which could potentially be low cost materials), such as Cu2ZnSnS4 or SnS. In this doctoral dissertation, we will investigate some aspects of SnS (tin sulphide), in view of its application as absorber layer for thin film solar cells. Tin sulphide is characterized by excellent optoelectronic properties (direct band gap in the region of the maximum theoretical efficiency, excellent absorption coefficient, and shows intrinsically p-type conduction), which makes SnS a promising candidate for the photovoltaic of the future. In the first part of this thesis, we will discuss the issues related to the deposition apparatus, and the strategies applied to solve them. Afterwards, the SnS based solar device, which exhibited the best performance, will be described and discussed: our result is consistent with similar processes from international laboratories. Since the reproducibility of this result has been observed to be a complex task, we will study its origin. A possible correlation between the performance of our devices and the thermal history of the SnS raw material used to evaporate the absorber layer has been suggested. Then, since even the best performing device exhibited a poor performance, i.e. far from the theoretical limit for a material with the SnS energy band gap, we will study the effects of several post deposition treatments, designed to enhance optoelectronic characteristics by improving the crystalline quality of the absorber material. Similar post deposition treatments are fundamental in other technologies, as in the CdTe case. We will study two types of thermal treatment: those taking place in a controlled atmosphere and those in air, by adding different compounds (with and without chlorine) to promote the absorber layer recrystallization process. The results will be discussed case by case. Up to now, we focused on the improvement of the absorber layer to enhance the performance of our devices. In the last part of this thesis, we will investigate some alternatives for the other layers constituting the solar device: the front and back contact, and the n-type semiconductor material which completes the p-n junction.
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GAUR, SHAILENDRA KUMAR. "HEAT & MASS TRANSFER ANALYSIS OF GOLD, TIN & INDIUM THIN LAYER DEPOSITION ON SURFACE." Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14778.
Повний текст джерелаАнотація:
The surface temperature is required to specifying the temperature of the evaporating Gold, Tin and Indium source using constant elements for turn off the refinement in the post-processing settings. The present work represents the modeling of nanoscale Gold, Tin & Indium films by computing the film thickness, mass deposited on the substrate and mass transfer rate on silicon substrates with time dependent model using BDF solver. Gold is deposited by thermal evaporation process 34-38 nm by evaporating at temperature of 2000 °K in the vacuum of 50 Pa. Mass of gold deposited for 60 sec is 5.8 x 10-6 kg with mass transfer rate of 9.9 x 10-8 kg/sec. The SEM micrographs shows the smooth and uniformly distributed nanoscale gold film on silicon and the average grain size of gold is 12-30 nm. The XRD analysis shows the polycrystalline face centered cubic (fcc) structure in preferential (111) plane. Tin and Indium is evaporated from a resistively heated evaporator source at a temperature of 1855 °K and 1485 °K respectively in a pressure (vacuum) of 100 Pa onto silicon surface held on a fixed surface. The film thickness varies between 144 nm to 165 nm for Tin and 160 nm to 183 nm for Indium across the sample after 60 sec of deposition, with radial symmetry about the midpoint of the source. The film thickness as well as mass deposited at a point increases linearly with time. Like gold mass deposited & mass transfer rate for tin and indium also computed from the flux arriving on the substrate. Since the angular distribution is of particular interest in this model, by increasing the integration resolution to a maximum value for ensuring the most accurate angular resolution when computing the flux. The SEM micrographs of Tin and Indium at different magnifications shows the 100nm to 1microns grain size along the grain boundaries. Similarly, XRD analysis with Kα (wavelength 1.541874) shows the peaks of intensity at different 2θ angles for different orientations of planes with polycrystalline structure. The XRD of tin shows tetragonal polycrystalline structure in preferential (101) plane while XRD for indium shows tetragonal bcc structure in preferential (103) plane for tin & indium thickness of 164 nm, 183 nm respectively. Deposited gold, tin & indium film thickness measured from Dektek surface profiler at different points on the substrate surface.
41
Tsai, Wei Tao, and 蔡維道. "The Study of Copper-Zinc-Tin-Sulfide Thin Film Prepared by Evaporation and Sulfurisation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/17815306951236066473.
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Hsieh, Ming-Hao, and 謝明浩. "Structural properties of copper-zinc-tin-sulfur (CZTS) thin film fabricated by co-evaporation method." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/93933273811371970805.
Повний текст джерелаАнотація:
碩士逢甲大學
光電學系
101
In this study, the copper-zinc-tin-sulfuride (CZTS) thin-film was synthesized via co-evaporation and sequent sulfuration process. Copper, zinc and tin were used as the source for co-evaporation process. The sulfur powder was used for sulfuration process under high temperature 550 oC. The influence of sulfuration time (0.5 hr, 1 hr, 1.5 hr, 2 hr) on characteristic of CZTS thin-film was discussed. The morphology and compositional ratio of the as-fabricated CZTS thin-film was investigated used SEM and EDS, respectively. When the sulfuration time increases, the surface of CZTS thin-film is denser. In the XRD and Raman spectra of post-sulfurated sample, the purity CZTS crystalline phase was found. The band gap of the CZTS with sulfuration time 2 hr2 is around 1.2 eV in the photoluminescence spectra and the CZTS thin-film has the p-type semiconductor behavior in the Hall measurement.
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ZAN, SHI-WEI, and 詹世偉. "Preparation and characterization of Indium-Tin-Oxide deposited by direct thermal evaporation of metal Indium and Tin." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/21530797670498052337.
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44
Chang, Chia-Hua, and 張家華. "Growth and Photovoltaic Applications of Indium Tin Oxide Nanostructures Using Electron Beam Evaporation." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/14752975434876605238.
Повний текст джерелаАнотація:
博士國立交通大學
光電工程學系
100
Indium-tin-oxide (ITO) has been a useful material as transparent conductive electrodes for the last two decades. Both solar cells and light-emitting-diodes benefit from the property of ITO to improve the conversion efficiency or light extraction, respectively. In this work, we developed a growth method to deposit ITO nanostructures, including the nano-columns, nanowhiskers, and nanorods. These nanostructures were applied for the GaAs-based, Si-based, and polymer-based solar cells, to reduce the surface reflectance or increase carrier collection. We further investigated the growth mechanism of ITO nanostructures which was dominated by the tin-induced self-catalytic vapor-liquid-solid (VLS) and the vapor-solid (VS) growth mechanism. The growth process could be divided into three steps: (1) nucleation, (2) column growth, and (3) side branch growth. We show evidence of the initial droplets formation to confirm the existence of the liquid phase. The core-shell structure had been observed in the TEM image of ITO nanorods, and hence the EDX analysis demonstrated higher concentration of tin in the shell than that in the core. The shell layer could absorb ITO vapor during the growth of ITO nanowhiskers. After investigation of the growth mechanism of ITO nanostructures, the applications had been discussed. First, we deposited the oriented ITO nano-columns on GaAs-based solar cell to provide broadband antireflection. Therefore, the conversion efficiency of the ITO nano-columns GaAs-based solar cell increased by 28% compared to a cell without any AR treatment. Next, we deposited the ITO nanowhiskers on the micro groove textured Si-based solar cell to combine the nano-and micro-textured antireflective coating. The compound antireflective structures increased light harvesting in the near-infrared. The conversion efficiency of the combined antireflective coated Si-based solar cell achieved 17.2%, compared to 16.1% of the conventional Si based solar. Finally, the ITO nanorods were prepared on ITO glass which functioned as three-dimensional (3D) nanoelectrode. The nano-electrode increased the hole collection efficiency for the organic solar cell. Compared to the organic solar cell with a flat electrode, the conversion efficiency and lifetime of the ITO nano-electrode organic solar cell increased by 10%, and 100%, respectively. We then conclude the growth and photovoltaic applications of the ITO nanostructures and provide future outlooks.
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Chiu, Li-Yen, and 邱立言. "Structure and mechanical properties of AlSiN/TiN multilayer deposited by cathodic arc evaporation." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/47608317571405371385.
Повний текст джерелаАнотація:
碩士明道大學
材料科學與工程學系碩士班
99
In this thesis, the bigger particle defect of AlSiN/TiN multilayer which was coated by using Cathode Arc Deposition (CAE) systems was studied. The rotation speed of the sample holder on process was changed when AlSiN/TiN multilayer was coated and the mechanical property and structure of multilayer ware measured. The advantage of CAE system is that it can use alloy target and it owns better uniformity, stronger adhesion and higher deposition rate. The advantage of multilayer films is not only that it combines the characteristics of each single film, also it significantly improve the hardness, adhesion loss. The mechanical properties of multilayer films are better than the one of single-layer. Multilayer film has more excellent performance; however, very few researches study the rotation speed on the coating process. Many evidences prove that the different rotation speed on the process can change adhesion wear, hardness of thin films, and indeed increase or decrease the thin film lifetime. In this study, the coating time was kept the same but the rotation speed and period number are changed. The change of mechanical structure with different period number was explored. The range of rotation speed is from 1 RPM to 16RPM. The mechanical properties such as surface hardness, adhesion and wear behavior are compared. The surfaces and cross sections of AlSiN / TiN multilayer are observed by using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Water Contact angle. The microstructures of thin films were analyzed by using X-ray diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). The adhesion was measured by using Rockwell Hardness Test and the Scratch Test. The hardness of films was measure by using Nanoindentation Test. The friction coefficient of film was measured by using the Wearing Test tests.
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Lin, Che-Yu, and 林哲宇. "Synthesis of Tin Oxide Nanowires by Thermal Evaporation and Application of Field Emission." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/13539095624384016099.
Повний текст джерелаАнотація:
碩士國立中正大學
化學工程研究所
99
This research was devoted to synthesize tin dioxide nanowires on the Si wafer by a thermal evaporation method and estimation of the field emission properties. The research was divided into two parts. The first part of the research was production. We used Au metal particles and silicon wafer as the catalyst and substrate , respectively , and use SnO powder as the evaporation source for the experiments. The result found that the diameter of SnO2 nanowires was changed by experiment parameters . SnO2 nanowires’ diameter were about 50~65 nm with the synthesis temperature of 1000℃. In addition , we found that the diameter decreased by increasing the amount of oxygen gas. The SnO2 nanowires were about 15~35 nm. In the second part of the research was the study of field emission properties. As-synthesized SnO2 nanowires was used as the cathod. The lowest turn-on field value was 1V/μm using 10~15nmSnO2 nanoemitters. We found that the turn-on field value was increased by increasing the diameter of SnO2 nanowires. The highest field enhancement factor value was 9650 usingt 15~20 nm SnO2 nanoemitters , The field enhancement factor value was decreased by increasing the diameter of SnO2 nanowires.
47
Huang, Meng-Shu, and 黃孟書. "Fabrication and characterization of Indium Tin Oxide transparent conductive films by Electron-Beam Evaporation." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/yv5b2a.
Повний текст джерелаАнотація:
碩士國立虎尾科技大學
光電與材料科技研究所
95
Abstract ITO is the most popular material for transparent electrical conduction film of commercial applications. There are several applications based on its excellent properties such as good conductivity, high transmittance rate for visible light, high absorbability for ultraviolet region and good chemical stability. This thesis studies the e-beam vaporized ITO thin film on glass substrate. The optical and electrical properties were studies with several process parameters such as the flow rate of oxygen, growth temperature, e-beam accelerated voltage. Systematic studies for the ITO related process parameters in the e-beam technology were well done in this thesis. With well controlled ITO film with process parameters optimized in the thesis, sheet resistance as low as 9.8(Ω/□) and high transparency as 95% with wavelength 470nm can both be achieved.
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Jie, Chen Zheng, and 陳政傑. "A study of indium tin-oxide transparent conductive oxide films by using electron-beam evaporation." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/60540112983326686828.
Повний текст джерелаАнотація:
碩士明新科技大學
化學工程與材料科技系碩士班
101
Transparent conductive electrodes with high transmittance and low resistance to optoelectronic device have gradually been widely used，such as touch panel、solar call、liquid crystal displays、with the rapid expansion of these product markets、the growth transparent conductive electrode rapidly increase in demand.Wherein the Indium tin oxide (Indium Tin Oxide; ITO) plays the important role of the conductive electrodes in a plane display. ITO film having a low resistance, and have a high transmittance in the visible range, the method of the preparation of indium tin oxide, mainly by sputtering method and electron beam deposition method, wherein the electron beam deposition method does not cause the surface of the elementinjury, and therefore subject to widespread attention. In this study, using an electron beam deposition method a growing Indium tin oxide thin film on the sodaline glass. Study their structural, electrical and optical properties of the thin film micro different deposition thickness, substrate temperature, spot oxygen flow and subsequent heat process.Using X-ray diffraction analyzer crystalline; Scanning electron microscope to observe the surface morphology of the sample; UV / VIS / NIR spectrometer transmittance ; sheet resistance of the four-point probe studies; Hall effectThe measurement to obtain the carrier concentration and the mobility of the thin film. The interpretation of the results, indium tin oxide film at a substrate temperature of 200 oC growth ITO film 100 nm thin film growth leads to 8 sccm O2 annealing at 300 ℃ in the 550nm transmittance of 98%, you can get a better quality factor of 0.055Ω-1, the experimental results using an electron beam vapor deposition by appropriate annealing the transparent conductive film of low resistance and high transmittance can be obtained.
49
謝明穎. "Study on the Synthesis, Optical and Electrical Properties of Tin-Doped Indium Oxide Nanowires by Thermal Evaporation Method." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/59130193560766787511.
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Gabriel, Brian M. Wolfe Douglas E. "Synthesis-structure-property-performance relationships of tin, CrN, and nanolayer (Ti,Cr)N coatings deposited by cathodic arc evaporation for hard particle erosion resistance." 2009. http://etda.libraries.psu.edu/theses/approved/PSUonlyIndex/ETD-3477/index.html.
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