Thèses sur le sujet « Lithic substrate »
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Lins, Leila Cristina Rosa de. « Propagação da lichieira por alporquia em diferentes substratos e épocas do ano ». Universidade Federal de Viçosa, 2013. http://locus.ufv.br/handle/123456789/4593.
Texte intégralConselho Nacional de Desenvolvimento Científico e Tecnológico
The aim of this study was to assess the influence of different times of the year and substrates on the rooting of air layers of lychee (Litchi chinensis Sonn.) for the production of seedlings to ensure the formation of uniform and productive orchards. Air layers were done in plants of the Bengal cultivar using leafy and healthy woody branches, with about 1.0 to 1.5 cm in diameter, in which complete girdling were performed with 2.0 cm wide at a distance of 30 to 40 cm below the apex. Then the branches were wrapped in moistened substrate. Air layering was made at six times of the year (January, March, May, July, September and November) and two substrates were used (coconut fiber and sphagnum) in a 6 x 2 factorial design in a randomized block with ten replicates, each block represented by a matrix plant. After 90 days, layers were separated from the matrix plant and evaluated for rooting and callus formation; root number, considering only the primary roots; length, area, volume and diameter of the roots; dry mass of roots and calluses, in addition to the dry mass of shoots (leaves and stems). The months of January, March, September and November showed the best results for allanalyzed variables related to rooting. With respect to the substrates, the only difference was in the months of January and March regarding root number and dry mass of roots, where the sphagnum showed the best results. The month of July was more favorable to the formation of calluses. The period between September and March was more suitable to the propagation of lychee, when there were rooting percentages above 90%, in addition to the formation of large amounts of roots.
Neste estudo, objetivou-se verificar a influência da época do ano e de diferentes substratos no enraizamento de alporques de lichieira (Litchi chinensis Sonn.), visando à produção de mudas que assegurem a formação de pomares uniformes e produtivos. Foram feitos alporques em plantas da cultivar Bengal, utilizando ramos lenhosos bem enfolhados e sadios, com cerca de 1,0 a 1,5 cm de diâmetro, nos quais foram realizados anelamentos completos de 2,0 cm de largura, à distância de 30 a 40 cm abaixo do seu ápice. Em seguida, os ramos foram envoltos por substrato umedecido. Foram avaliadas seis épocas de realização dos alporques (janeiro, março, maio, julho, setembro e novembro) e dois substratos (esfagno e fibra de coco), em um esquema fatorial 6 x 2, no delineamento em blocos casualizados com dez repetições, sendo cada bloco representado por uma planta-matriz. Passados 90 dias, os alporques foram separados da planta-matriz e avaliados quanto à porcentagem de enraizamento e de calejamento; ao número de raízes, considerando apenas as raízes primárias; ao comprimento, à área, ao volume e ao diâmetro das raízes; à massa seca de raízes e calos, além da massa seca da parte aérea (folhas e caule). Os melhores resultados para todas as variáveis relacionadas ao enraizamento analisadas foram verificados nos meses de janeiro, março, setembro e novembro. Com relação aos substratos, houve diferença apenas nos meses de janeiro e março para número de raízes e massa seca de raízes, tendo o esfagno apresentado os melhores resultados. O mês de julho foi mais propício à formação de calos. O período compreendido entre os meses de setembro e março foi o mais propício à propagação da lichieira, quando foram obtidas porcentagens de enraizamento superiores a 90%, além da formação de grande quantidade de raízes.
Jeyaranjan, Aadithya. « Adhesion of Germanium Electrode on Nickel Substrate for Lithium Ion Battery Applications ». Scholar Commons, 2015. https://scholarcommons.usf.edu/etd/5509.
Texte intégralEustache, Etienne. « Microsystèmes de stockage d'énergie sur substrat 3D ». Nantes, 2016. https://archive.bu.univ-nantes.fr/pollux/show/show?id=1e832b83-4efd-4a39-8aaf-10735e08b591.
Texte intégralProviding autonomy to miniaturized electronic devices is a challenge. New research directions should be investigated in order to increase the performance of Liion microbatteries (MB) and micro-supercapacitors (MSC). Developing power sources with a 30 topology instead is a promising approach to surpass the planar devices energy density. Ln this exploratory thesis, we realized 30 structures at the micrometric scale by deep etching of a silicon substrate. This architecture is used as a common base to fabricate Li-ion MB and MSC. A TiO2 MB negative electrode has been realized by atomic layer deposition (ALD) on top of the microstructures. Electrochemical characterizations show a proportional increase (x30) of the capacity with the specific surface area of the 30 architecture. A conformal lithium phosphate (Li3P04) film has also been developed by ALD. The ionic conductivity (=4. 10-7 S/cm) and the limited thickness (60 nm) of the layer establish this material as a 30 MB potential solid-state electrolyte. Furthermore, MSC with interdigitated 30 electrodes have been fabricated. Mn02 thin films have been deposited by electrodeposition on top of the 30 substrate. Results demonstrate that this approach allow to achieve pseudocapacitive devices with high specific capacitance
Gil, Rashapal Ram. « Aluminium and its alloy as substrates for the lithium rechargeable electrode ». Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363538.
Texte intégralvan, Lierop Jean. « Influence of variations in ceramic thickness and bonding substrate on the fracture resistance of lithium disilicate restorations ». University of the Western Cape, 2017. http://hdl.handle.net/11394/6626.
Texte intégralRestorative dentistry aims to replace lost or damaged tooth structure with durable and life-like alternatives. To accommodate the inherent limitations and weakness of the restorative materials, preparation techniques often require the sacrifice of healthy tooth structure to create enough restorative space. This can lead to weakening of the remaining tooth structure, with subsequent damage or catastrophic failure. When using indirect restoratives, the development of adhesive luting agents (adhesive cements) and stronger allporcelain restorations (lithium disilicate) has contributed to the development of “minimally invasive” preparation techniques and concepts such as cavity design optimization (CDO) and bio-substitution. With these techniques, resin materials are combined with ceramic restoratives in an attempt to not only produce strong restorations, but also increase the longevity of the remaining tooth. The clinician needs to therefore find the ideal preparation design that combine such materials to produces a clinically performing restoration while increasing the strength and longevity of the underlying tooth.
Henrot, Fabien. « Composants à hauts facteurs de forme pour les résonateurs acousto-électriques et les dispositifs électro-optiques sur substrats mono-cristallins ». Thesis, Besançon, 2015. http://www.theses.fr/2015BESA2032/document.
Texte intégralOver the past decades, minutiarization and compacity have become a focus subject for companies specialisedin the manufacturing of radio-frequency components. Active components are typically manuafctured onsilicon wafers with well-known structuring methods. Passive ones are often manufactured on single cristalsuch as Quartz or Lithium Niobate, especially for acoustic wave generation or lightwave guiding. Theguiding of optical or acoustical waves leads to the manufacturing of sensors or filters which can be usedfor telecommunications or for the industry. Improvement in waveguiding allows for less power-consuming andmore compact devices but a 3D-structuring is usually required. This technology readness is high leveled forsilicon structuring but not for single crystals such as Lithium Niobate. This work presents the development andthe manufacturing of high aspect ratio three-dimensionnal structures in single-crystals using precise sawing.These structures show an optical waveguiding capability which allow the improvements of electro-opticmodulators or filters. Combined with a periodic reversing of Lithium Niobate polarization, these structuresallows for bulk acoustic wave generation leading to high electromechanical coupling and equivalent phasevelocity resonant modes. In non-linear optic field, this kind of structures lead to the improvement of secondharmonic generation e_ciency by reducing the cross section of waveguide. The manufactured devices in theframework of this project can actuelly be used in several domains of physic
Palanisamy, Asha. « High Energy Density Battery for Wearable Electronics and Sensors ». University of Dayton / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1480511507315736.
Texte intégralBrigouleix, Catherine. « Elaboration et étude de couches minces électrochromes déposées par pulvérisation cathodique : mise en œuvre de démonstrateurs sur substrat flexible ». Bordeaux 1, 2003. http://www.theses.fr/2003BOR12648.
Texte intégralThe aim of this thesis was to study flexible electrochromic devices. They can modulate their visible and near infra-red transmittance under polarization. They are constituted of a stack of thin layers : i. ) an electrochromic active layer based on nanocrystaline WO3, coloured under cathodic bias, ii. ) a lithium-ion conducting electrolyte which can be based either on photopolymerizable organic constituents, or on an inorganic film (LiPON), iii. ) an ion storage counter electrode, which can be either an anodic colouring material such as nanocrystalline ''LixNi0. 5O'', or an optically passive oxide such as nanocristalline lamellar ''V2O5/TiO2''. This set of layers is sandwiched between two transparent conductive electrodes deposited on polyethyleneterephtalate flexible substrates. Electrochromic layers and inorganic electrolyte were deposited by cathodic sputtering. Correlation between deposition parameters, electrochromic properties and structural properties were established
Kang, Sangbeom. « The epitaxial growth of GaN and A1GaN/GaN Heterostructure Field Effect Transistors (HFET) on Lithium Gallate (LiGaO₂) substrates ». Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13903.
Texte intégralRavi, Ajaay. « Run-Time Active Leakage Control Mechanism based on a Light Threshold Voltage Hopping Technique (LITHE) ». University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1302550444.
Texte intégralGaniek, Maximilian [Verfasser], et Paul [Akademischer Betreuer] Knochel. « Metalation and Halogen-Lithium exchange of sensitive substrates and mild ester homologation in continuous flow / Maximilian Ganiek ; Betreuer : Paul Knochel ». München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1172634327/34.
Texte intégralBohne, Laura [Verfasser], Wolfram [Akademischer Betreuer] Jaegermann et Helmut F. [Akademischer Betreuer] Schlaak. « Integrierte 3D-Lithium-Ionen-Dünnschichtbatterien : Dünnschichtkathoden auf strukturierten Substraten und elektrochemische Eigenschaften / Laura Bohne. Betreuer : Wolfram Jaegermann ; Helmut F. Schlaak ». Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2012. http://d-nb.info/1106114965/34.
Texte intégralHallot, Maxime. « Micro-batteries tout solide en technologie Li-ion sur substrats Silicium planaires et tridimensionnels pour objets connectés ». Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I115.
Texte intégralMiniaturized sensors for Internet of Things (IoT) application is in expansion since the last 10 years. All solid-state lithium-ion battery is a promising candidate. Nevertheless, in spite of high technological readiness level, planar micro-batteries suffer from a lack of energy density meaning that it is necessary to develop new architectures to fullfill the performances requirements. 3D structures is needed for such application and this work is focused on the synthesis of positives electrodes with high storage capacity and high operating voltage by Atomic layer deposition (ALD). In the frame of this work,we will rely structurals and electrochemicals properties by differents characterisations techniques for batteries materials
Denoyelle, Elise. « Développement d’une microbatterie Li-ion 3D & ; Étude d’une anode de silicium amorphe déposée par LPCVD sur substrat 3D ». Caen, 2010. http://www.theses.fr/2010CAEN2005.
Texte intégralSince the first Integrated Circuits, the Semiconductors industry has innovated in the field of miniaturization at the device level. For several years, NXP company has designed sb-SiP systems (silicon-based System in Package) which allow the insertion of passive components into passive devices on which an active device is mounted. The concept depends upon the PICS technology (Passive Integration Connective Substrate) which allows the integration of capacitors of high values. Considering the achievement of this process, NXP wishes to develop new products as 3D Li-ion microbatteries. At first, we developed a partnership approach in order to acquire competences in lithium-ion technology. The different contacts allow us to define more precisely the technological components needed in order to create a 3D-microbattery on silicon substrate. In a second part, we adress the study of an amorphous silicon thin film anode deposited by LPCVD (Low Pressure Chemical Vapor Deposition). The objective of the study is to measure the electrochemical performances of the amorphous silicon anode on 2D and 3D silicon substrate
Jones, Jessica C. « Atomic Layer Deposition of H-BN(0001) on Transition Metal Substrates, and In Situ XPS Study of Carbonate Removal from Lithium Garnet Surfaces ». Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703333/.
Texte intégralBrigouleix, Catherine. « Elaboration et étude de couches minces électrochromes déposées par pulvérisation cathodique. Mise en oeuvre de démonstrateurs sur substrat flexible ». Phd thesis, Université Sciences et Technologies - Bordeaux I, 2004. http://tel.archives-ouvertes.fr/tel-00005358.
Texte intégralLétiche, Manon. « Élaboration de matériaux pour microbatterie 3D Li-ion par dépôt de couches atomiques (ALD) et caractérisations structurales operando ». Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10183/document.
Texte intégralIn order to address the demand on energetic needs to sustain nomad and miniaturized electronic devices, micro-devices performance for energy storage such as Li-ion microbatteries (MB) have to be improved. An attractive way to meet the required performance consists in using 3D topology increasing the specific surface while keeping the initial surface footprint (in the mm2 range) which is significantly enhancing the delivered energy density of the MB. The development of thin film technologies such as ALD enabling conformal deposition makes it possible. In the framework of this thesis, a solid electrolyte (Li3PO4) has been developed and optimized by ALD, on a 3D micro-architectured silicon substrate obtained by microfabrication techniques. A positive electrode (LiMn1.5Ni0.5O4) has also been developed and optimized as a function of the deposition parameter by RF sputtering deposition on a Si/Al2O3/Pt substrate. A volumetric capacity of 63 µAh.cm-2.µm-1 has been measured for a film of 420 nm thick obtained at 0.01 mbar and then annealed at 700°C under air atmosphere. Finally, a prototype has been proposed to realize an electrochemical cell for the purpose of in situ/operando follow-up by XRD of a thin film electrode deposited on silicon substrate
Braun, Loïc. « Composants à ondes élastiques de surface pour le filtrage à gabarits maîtrisés aux fréquences radios pour applications spatiales et professionnelles ». Thesis, Besançon, 2015. http://www.theses.fr/2015BESA2020/document.
Texte intégralThis thesis deals with the development of surface acoustic wave devices (SAW) for filtering applications in the VHF and UHF bands. Several filter structures are studied. The first ones are longitudinally coupled resonator filters (LCRF) manufactured on Quartz with a relative pass-band narrower than 0,1 % centered at about 1 GHz. These filters have been fabricated and characterized, yielding less than 5 dB insertion loss with rejection levels in excess of 20 dB as predicted by our P-matrix model. One of these filters has been mounted in an oscillator to validate its characteristics.To improve the design of such filters, we have developed a model accounting for transverse mode contributions on their spectral function. Comparisons between theory and experiment emphasizes the accuracy of the developed model. We also have investigated impedance element and slanted transducers (fan-shaped) filter structures to produce filters with relative pass-band ranging from 1 to 15 % in the 100 − 300 MHz frequency range. For each type of filters, we have developed a model to predict their electrical response. A balanced-bridge filter configuration with a 2 % relative pass-band and four fan-shaped filters with pass-band larger than 10 % have been fabricated and characterized. Finally, we have studied two approaches for the development of SAW devices operating at frequencies in the vicinity of 3 GHz. The first approach exploits Diamond-based substrates, providing phase velocity higher than 5 km.s−1. The second one uses a nano-imprint lithography process to reduce the pitch of electrode gratings
ROSSI, FEDERICO. « Study of exopolysaccharide-producing cyanobacteria in biofilm growing on lithic substrate and in extreme environments ». Doctoral thesis, 2010. http://hdl.handle.net/2158/547903.
Texte intégralChen, Yen-ming, et 陳彥名. « Molecular beam epitaxial growth of nonpolar ZnO on lithium aluminate substrate ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/31570381553949354041.
Texte intégral國立中山大學
材料與光電科學學系研究所
100
Both non-polar (10-10) (m-plane) and polar (0001) (c-plane) zinc oxide (ZnO) have a good lattice match with lithium aluminum (LiAlO2, LAO) (200) substrate, so it is difficult to control the epitaxial orientation. Therefore, this research is to explore how the growth parameters influence on the crystal orientation of ZnO film grown by plasma assisted molecular beam epitaxy. The experimental results show that m-plane ZnO can be grown with low zinc flux and low oxygen pressure. Increasing zinc flux and oxygen pressure will lead to increase in growth rate, and consequently, c-plane ZnO will nucleate on the substrate besides m-plane zinc oxide. The substrate temperature is one of the main factors that influence the choice of zinc oxide epitaxial orientation. High temperature will promote the m-plane zinc oxide nucleation, while low temperature will conduct to the c-plane zinc oxide nucleation. Under low zinc flux and low oxygen pressure, epitaxy of ZnO with different crystalline orientations can be achieved through changing the substrate temperature. The surface morphology and roughness of the substrate will affect the particle size and surface morphology of ZnO epilayers. When the substrate is smooth, the crystal size of the epitaxial film is large and the surface is flat with many rectangular stripes, taking on the platform-like morphology. If the substrate is rough with many scratches, the particle size becomes small and the surface is granular-like and rather rough. Furthermore, when the substrate is rough, it is difficult to control the different orientations of ZnO epitaxial films through changing the substrate temperature.
Stone, Barbara Ann. « Physical characterization of lithium niobate thin films on silicon substrates ». Thesis, 1988. http://hdl.handle.net/1911/13320.
Texte intégralWang, Shunxi. « Lithium niobate thin films on diamond substrates for SAW devices ». Thesis, 2001. http://hdl.handle.net/1911/18047.
Texte intégralHuang, Hung-Jia. « Optical characterization of lithium niobate thin film waveguides sputtered on sapphire substrates ». Thesis, 1991. http://hdl.handle.net/1911/13528.
Texte intégralBohne, Laura. « Integrierte 3D-Lithium-Ionen-Dünnschichtbatterien : Dünnschichtkathoden auf strukturierten Substraten und elektrochemische Eigenschaften ». Phd thesis, 2012. https://tuprints.ulb.tu-darmstadt.de/2957/1/Dissertation_LB_web.pdf.
Texte intégralHuang, Hsin-Shun, et 黃新舜. « Design and Fabrication of Ridge-type Directional Coupler on Gamma-ray Irradiated Lithium Niobate Substrate ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/98144096587498236544.
Texte intégral國立臺灣大學
光電工程學研究所
99
In this thesis, ridge waveguides are fabricated by using proton exchange and wet etching in gamma-ray irradiated lithium niobate(LiNbO3). Experimental results show the depths and aspect ratios of ridge structures are all improved, which gives rise to optical fields of higher aspect ratios and electro-optic modulators with better characteristics. The ridge structures are obtained by proton exchange for 8 hr with various acid sources and etched for 8 hr with a mixture of hydrofluoric acid and nitric acid. The deepest depth and the aspect ratio of ridge structure are 4.472μm and 1.3 when the dosage of gamma-ray irradiation is 162.5krad. Moreover, the coupling length is shortened by 8.2% when a ridge-type directional coupler is fabricated with gamma-ray irradiated lithium niobate, which indicates that coupling effect is enhanced due to gamma-ray irradiation. And the half-wave voltage is decreased by 37.94%, and the extinction ratio is increased by 46.54%. Thus, it shows that gamma-ray irradiation is advantageous for the improvement of lithium niobate integrated optical waveguides.
Lin, Albert Jian. « Lithium niobate thin films deposited on silicon substrates for SAW applications (surface acoustic wave) ». Thesis, 1996. http://hdl.handle.net/1911/14063.
Texte intégralLi, Yu-Zhi, et 李育誌. « Periodic Segmented Waveguides and Ridge Optical Waveguides Based on Z-cut Lithium Niobatgte Substrates ». Thesis, 2002. http://ndltd.ncl.edu.tw/handle/05646476412629395757.
Texte intégral大同大學
光電工程研究所
90
In this thesis, the proton-exchanged technique is used to fabricate several waveguide on z-cut Lithium Niobate substrates . This technique has the advantages such as simple treatment, low loss and low cost. At the same time, we also use the Inductively Coupled Plasma Reactive Ion Etching, ICP-RIE to etch the Lithium Niobate. By mixture of 、Ar and . We find that if we input different proportion of Hydrogen, we can get the different etching rate and it also affects the roughness of the etched surface. Finally we also take use of the technique to fabricate the ridge-type waveguide. Both theoretical analysis and experimental measurement has been carried out for the comparison. In this thesis, the near-field(NF) method is applied to the index profile measurement. However, there exist noise problem. We propose the use of a field function calculated by variation method to smooth the measured intensity profile without or loss of accuracy. A new trial field, namely, the modified Hermite-Gauss (MHG) function has been used. We have coupled laser beam(at 0.6328 μm wavelength) into devices by virtue of the end-fire coupling method, have also verified the therries .
Rua, João Luís dos Santos Heleno da. « Baterias de lítio em filme fino : fabrico e caracterização de LiCoO2 para utilização no cátodo ». Master's thesis, 2015. http://hdl.handle.net/1822/47229.
Texte intégralEsta dissertação inclui a deposição e caracterização do Óxido de Lítio Cobalto (LiCoO2) para utilização como cátodo de uma bateria de lítio em filme fino recarregável e flexível. Atualmente, a maior desvantagem desta tecnologia de baterias é a capacidade reduzida. Com este trabalho pretende-se investigar processos de melhoria da capacidade e durabilidade das baterias de lítio em filme fino, passando pelo aumento dos números de ciclos de cargas/ descargas que as baterias conseguem realizar até à sua degradação. Um desses processos consiste na tentativa de obter filmes de LiCoO2 com uma determinada orientação estrutural a temperatura reduzida (~400 ºC), temperatura esta compatível com o substrato flexível de Kapton® utilizado. Para isso recorreu-se, a dois tipos de tratamento térmico: recozimento dos filmes de LiCoO2 num forno convencional e recozimentos dos mesmos por via laser. Outro processo consiste na tentativa de aumentar a área de contacto entre os vários filmes constituintes de uma bateria (sem aumentar as dimensões da bateria), através da incidência do feixe laser num substrato de Kapton®. Para além disto, o ânodo de lítio foi substituído pelo ânodo de germânio que possui uma elevada capacidade gravimétrica (1384 mAh/g) [1], uma elevada difusão de iões de lítio, alta capacidade de inserção/extração de iões de lítio e consegue suportar elevadas taxas de carga/descarga, conduzindo a um melhor desempenho na ciclagem da bateria. A bateria a fabricar será constituída por um substrato de Kapton® 500HN; uma camada de Si3N4, um filme fino de LiCoO2 como cátodo e um filme de LiPON como eletrólito depositados por RF sputtering. O ânodo, inicialmente, foi um filme fino de lítio depositado por evaporação térmica e posteriormente utilizou-se germânio depositado por e-beam. Os contactos são platina depositada por DC sputtering e titânio depositado por e-beam. Para caracterização da bateria recorreu-se a análises de ciclos de carga/descarga utilizando o potencióstato Gamry 600; AFM e microscopia ótica para o substrato de Kapton®; espectroscopia Raman para os filmes de LiCoO2 com recozimento a laser e análises num microscópio SEM para verificar a adesão dos filmes finos.
This dissertation includes the deposition and carachterization of Lithium Cobalt Oxide (LiCoO2) as a cathode on a thin-film lithium-ion rechargeable battery in a flexible substrate. Nowadays, the biggest flaw in this battery technology is its low capacity. This work’s intention is to investigate new processes to improve the capacity and durability of thin-film lithium-ion batteries by increasing its cyclability untill its degradation.One of these processes consists in the attempt to obtain thin films of LiCoO2 with a certain structural orientation on a low temperature (~400 ºC), which is compatible with the Kapton® flexible substrate used.Two types of thermal treatments were used to achieve that: conventional furnace annealing and laser annealing. Another process consists in the attempt to increase the surface area between the many thin-film that form the battery (without increasing the battery’s dimensions), by using a laser to create patterns in the Kapton® substrate. Besides, the anode material (lithium metal) was replaced by germanium, which has a high gravimetric capacity (1384 mAh/g)[1], a high lithium ions difusion, high capacity of lithium ions insertion and extraction and is able to support high charging/discharging rates, which leads to a better performance in the battery’s ciclabillity. The fabricated battery had a Kapton® 500HN substrate; Si3N4, LiCoO2 (as cathode) and LiPON (as electrolyte) thin films deposited by RF sputtering. The anode, initialy, was a lithium thin film deposited by thermal vaporization, but later it was switched to germanium deposited by e-beam.The current collectors are: a Pt thin film deposited by DC sputtering (for the cathode) and a Ti thin film (for the anode) deposited by e-beam. As characterization it will be used the Gamry 600 potentiostate to cycle the battery; AFM and optical microscopy for the Kapton® substrate; Raman spectroscopy for the laser annealed LiCoO2 thin films and SEM analysis of the whole battery to analise the adhesion of the thin films.
« Finite Element Analysis of Silicon Thin Films on Soft Substrates as Anodes for Lithium Ion Batteries ». Master's thesis, 2011. http://hdl.handle.net/2286/R.I.8896.
Texte intégralDissertation/Thesis
Appendix H - Movies (zipped)
M.S. Mechanical Engineering 2011
Tsai, Chih-Hao, et 蔡志豪. « The effect of lithium manganese oxide as thin film positive electrodes by annealing treatment and substrate bias assisted sputtering ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/82263149598462231145.
Texte intégral逢甲大學
材料科學所
92
Abstract Secondary lithium batteries have been the primary power supply components for various portable electronic devices, such as cell phones and notebook computers. However, as the weight and volume of the portable devices continuously decrease, the search for smaller, lighter, and higher-power-density sources has never stopped. In order to meet these requirements, the concept of Thin Film Batteries (TFB), or all solid state micro-batteries, has therefore been of great interest. With only a few micron meters of thickness or less, thin film batteries are compatible with micron electro-mechanical devices, and can be the back-up power for SRAM, as well. This research uses LiMn2O4 as cathode material of thin film batteries. The applied substrate bias during sputtering of LixMn2-yO4 thin film will control the ion-bombarding energy and achieve the in-situ modification. Moreover, the air annealing will improve the properties of LixMn2-yO4 thin film, such as the capacity, discharge voltage and electric conductivity. The result shows that bias -20VDC will deposit LixMn2-yO4 film with some appropriate defects. These defects are expected to provide a flexible space which can help to maintain the spinel structure. These films have better cycle life and their discharge capacity can reach 122 mAh/g. The 600℃-1hr air annealing can increase effectively the characteristic of 0VDC deposited LixMn2-yO4 films. These air-annealed films can have a perfect spinel structure and exhibit a two-stage discharge voltage plate(4.1 and 3.9V).
« Study on Buckling of Stiff Thin Films on Soft Substrates as Functional Materials ». Doctoral diss., 2014. http://hdl.handle.net/2286/R.I.24814.
Texte intégralDissertation/Thesis
Ph.D. Mechanical Engineering 2014