Дисертації з теми "Amorphous-amorphous interfaces"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-40 дисертацій для дослідження на тему "Amorphous-amorphous interfaces".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Kast, Matthew. "Towards Tunable and Multifunctional Interfaces: Multicomponent Amorphous Alloys and Bilayer Stacks." Thesis, University of Oregon, 2017. http://hdl.handle.net/1794/22288.
Повний текст джерелаHassanali, Ali. "WATER AT MOLECULAR INTERFACES: STRUCTURE AND DYNAMICS NEAR BIOMOLECULES AND AMORPHOUS SILICA." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275314943.
Повний текст джерелаMews, Mathias [Verfasser], Bernd [Gutachter] Rech, i. Cabarrocas Pere [Gutachter] Roca, and Bernd [Gutachter] Szyszka. "Interfaces in amorphous/crystalline silicon heterojunction solar cells / Mathias Mews ; Gutachter: Bernd Rech, Pere Roca i Cabarrocas, Bernd Szyszka." Berlin : Technische Universität Berlin, 2016. http://d-nb.info/1156181437/34.
Повний текст джерелаRoss, Nick. "Interfacial Electrochemistry of Cu/Al Alloys for IC Packaging and Chemical Bonding Characterization of Boron Doped Hydrogenated Amorphous Silicon Films for Infrared Cameras." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849696/.
Повний текст джерелаLidbaum, Hans. "Transmission Electron Microscopy for Characterization of Structures, Interfaces and Magnetic Moments in Magnetic Thin Films and Multilayers." Doctoral thesis, Uppsala universitet, Experimentell fysik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-107941.
Повний текст джерелаFagas, Georgios. "Vibrational properties of complex solids." Thesis, Lancaster University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321898.
Повний текст джерелаVarache, Renaud. "Development, characterization and modeling of interfaces for high efficiency silicon heterojunction solar cells." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112279/document.
Повний текст джерелаThe interface between amorphous silicon (a-Si:H) and crystalline silicon (c-Si) is the building block of high efficiency solar cells based on low temperature fabrication processes. Three properties of the interface determine the performance of silicon heterojunction solar cells: band offsets between a-Si:H and c-Si, interface defects and band bending in c-Si. These three points are addressed in this thesis.First, an analytical model for the calculation of the band bending in c-Si is developed. It assumes a constant density of states (DOS) in the a-Si:H band gap. The influence of most parameters of the structure on the band bending is studied: band offsets, DOS in a-Si:H, interface defects, etc. The presence of quantum confinement at the interface is discussed. Analytical calculations and temperature dependent planar conductance measurements are compared such that the band offsets on both (p)a-Si:H/(n)c-Si and (n)a-Si:H/(p)c-Si can be estimated: the valence band offset amounts 0.36 eV while the conduction band offset is 0.15 eV. In addition, it is shown that the valence band offset is independent of temperature whereas the conduction band offset follows the evolutions of c-Si and a-Si:H band gaps with temperature. A discussion of these results in the frame of the branch point theory for band line-up leads to the conclusion that the branch point in a-Si:H is independent of the doping.Then, analytical calculations are developed further to take into account the real solar cell structure where the a-Si:H/c-Si structure is in contact with a transparent conductive oxide and an undoped buffer layer is present at the interface. Measurements of the planar conductance and of the interface passivation quality are interpreted in the light of analytical calculations and numerical simulations to open a way towards a method for the optimization of silicon heterojunction solar cells. It is particularly shown that a trade-off has to be found between a good passivation quality and a significant band bending. This can be realized by tuning the buffer layer properties (thickness, doping), the TCO-contact (high work function) and the emitter (defect density and thickness). Interestingly, an emitter with a high DOS leads to better cell performances.Finally, a new type of interface has been developed, that was not applied to heterojunction solar cells so far. The c-Si surface has been oxidized in deionized water at 80 °C before the (p)a-Si:H emitter deposition such that (p)a-Si:H/SiO2/(n)c-Si structures were obtained. A tunneling current model has been developed, implemented in the 1D numerical device simulator AFORS-HET and used to study the effect of a wide band gap interfacial layer (as it is the case for SiO2) on cell performance: the fill-factor and the short-circuit current are dramatically reduced for thick and high barriers. However, a SiO2 layer has only little impact on optical properties. Fabricated samples show a passivation quality halfway between samples with no buffer layer and with an (i)a-Si:H buffer layer: this is explained by the presence of a negative fixed charge in the oxide. The band bending in (n)c-Si is higher with an oxide layer than with an (i)a-Si:H buffer layer. Solar cells demonstrate that this new concept has the potential to achieve high power conversion efficiencies: for non-optimized structures, an open-circuit voltage higher than 650 mV has been demonstrated, while the oxide does not seem to create a barrier to charge transport
Luo, Haoming. "High frequency thermomechanical study of heterogeneous materials with interfaces." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI130.
Повний текст джерелаHeat transfer is actually intimately related to the sound propagation (acoustic transfer) in materials, as in insulators and semi-conductors the main heat carriers are acoustic phonons. The concept of the presence of interfaces has been largely exploited for efficiently manipulating phonons from long-wavelength to nanometric wavelengths, i.e., frequencies in THz regime, responsible for thermal transport at room temperature. In this thesis, the finite element method is used to perform transient analysis of wavepacket propagation in different mediums. I started with a parametric study of attenuation of acoustic wave-packets in a 2D semi-infinite elastic system with periodic circular interfaces. Three key parameters are investigated, including rigidity contrast, interface density and phonon wavelength. Different energy transfer regimes (propagative, diffusive, and localized) are identified allowing to understand the phonon contribution to thermal transport. Besides the circular interfaces, mechanical response and acoustic attenuation for different types of interfaces are also investigated, such as Eshelby’s inclusion, dendritic shape inclusion and porous materials with ordered/disordered holes. In order to extend the study to amorphous materials, I also considered a heterogeneous medium with random rigidities distributed in space according to a Gaussian distribution based on the theory of heterogeneous shear elasticity of glasses. Finally yet importantly, viscoelastic constitutive laws are proposed to take into account the frequency-dependent intrinsic phonon attenuation in glasses, with the aim of reproducing such intrinsic attenuation using a homogeneous viscous medium. Finite element simulation confirms that a continuum model may strictly follow the atomistic attenuation (G) for a well-calibrated macroscopic linear viscoelastic constitutive law. Compared with the experimental data in a-SiO2, our second constitutive law reproduces qualitatively and quantitatively the three regimes of acoustic attenuation versus frequency : successively Γ∝ω^2,ω^4,ω^2
Zhu, Kai Schiff Eric A. "Interface modulation spectroscopy and doping physics in amorphous silicon." Related Electronic Resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2003. http://wwwlib.umi.com/cr/syr/main.
Повний текст джерелаGandy, Amy S. "A Transmission Electron Microscopy study of the Interaction between Defects in Amorphous Silicon and a Moving Crystalline/Amorphous Interface." Thesis, University of Salford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502784.
Повний текст джерелаGandy, Amy Sarah. "A Transmission electron microscopy study of the interaction betweeen defects in amorphous silicon and a moving crystalline amorphous interface." Poitiers, 2008. http://theses.edel.univ-poitiers.fr/theses/2008/Gandy-Amy/2008-Gandy-Amy-These.pdf.
Повний текст джерелаL'endommagement induit par implantation de xénon dans le silicium a été étudié par microscopie électronique à transmission (MET). Les implantations réalisées à 350°C, à une énergie de 250keV et pour des fluences supérieures à >1x1016 Xe ions/cm2 conduisent à la formation d'une couche amorphe enterrée. Les observations effectuées sur les échantillons recuits montrent la présence d'une rangée de grandes cavités allongées dans la direction perpendiculaire à l'interface. Ceci suggère que, lors de la recristallisation du silicium, le déplacement simultané des deux interfaces entraîne le déplacement du gaz jusqu'à son confinement dans de larges bulles. Afin de mieux appréhender les mécanismes qui conduisent au mouvement des bulles, de l'hélium à faible dose a été implanté dans du silicium préalablement amorphisé par implantation de Li à basse température. L'implantation d'hélium dans le silicium amorphe conduit à la formation de bulles de forme irrégulière. Ce résultat diffère du silicium cristallin où des bulles sphériques sont obtenues pour des conditions d'implantation identiques. Les expériences réalisées ‘in situ’ dans le MET montrent clairement d'une part que les bulles sont poussées par l'interface, et d'autre part la nucléation de micromacles. Il a été mis en évidence au cours de cette étude que les bulles sont mobiles à plus basse température dans le silicium amorphe que dans la phase cristalline. Lors de la recristallisation, les bulles se trouvent alors confinées dans le matériel amorphe, ce qui résulte en leur coalescence et à la formation de larges bulles une fois que les deux fronts de recristallisation se sont rejoints. De plus, il a été établi que la formation de micromacles dans la région recristallisée est liée à un excès de défauts de type interstitiels dans la zone amorphe. Ce résultat est contraire aux modèles de la littérature qui suggèrent que les micromacles se forment soit sur des plans {111} soit sur les bulles
Gilchrist, Valerie A. "The adsorption of surfactant at the amorphous polymer-solution interface." Thesis, University of Surrey, 2002. http://epubs.surrey.ac.uk/844324/.
Повний текст джерелаDjurberg, Viktor. "Tailoring the Magnetic Properties of Amorphous TbCo Nano Films." Thesis, Uppsala universitet, Materialfysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-348209.
Повний текст джерелаWalczak, Malgorzata. "Role and properties of the confined amorphous phase of polymers." Phd thesis, Paris, ENSAM, 2012. http://pastel.archives-ouvertes.fr/pastel-00839174.
Повний текст джерелаLiu, Richard Yufeng. "Oxygen Transport as a Structure Probe for Amorphous Polymeric Systems." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1103694304.
Повний текст джерелаEggers, Tatiana M. "Surface and Interface Effects of Magnetoimpedance Materials at High Frequency." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7282.
Повний текст джерелаFavre, Wilfried. "Silicium de type n pour cellules à hétérojonctions : caractérisations et modélisations." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00635222.
Повний текст джерелаShin, Yun Kyung. "The water-amorphous silica interface: electrokinetic phenomena in a complex geometry, and treatment of interactions with biomolecules." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299587783.
Повний текст джерелаKoishi, Ayumi. "Mécanismes de nucléation des carbonates." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU032/document.
Повний текст джерелаPrecipitation and dissolution of calcium carbonate (CaCO3) are key processes in both natural and engineered systems due to their intimate association with the Earth’s carbon cycle. Precipitation usually occurs on foreign substrates since they lower the energetic barriers controlling nucleation events. This so-called heterogeneous nucleation results from the interplay between the fluid supersaturation and the interfacial free energies present at the substrate-nucleus-fluid interfaces. Despite the relevance of interfacial energies for the fate of heterogeneous nucleation, the current literature remains scarce in their absolute values, which limits the accuracy of reactive transport modelling. Of particular relevance to the carbon cycle, the formation of biominerals accounts for a major reservoir of the carbonate minerals in the lithosphere. Recent studies have revealed the existence of multistep nucleation pathways that involve formation of amorphous calcium carbonate (ACC), a metastable intermediate during the early stages of biomineral formation. Such amorphous precursors allow molding of the intricate shapes of biominerals, while their stability and crystallization kinetics are effectively controlled by multiple factors. Elucidating the underlying mechanisms is beneficial for the development of biomimetic materials.The first goal of this dissertation is to develop a predictive understanding of interfacial energy values governing CaCO3 heterogeneous nucleation as a function of specific physico-chemical properties of the substrates, such as hydrophobicity. This last was investigated using phlogopite, a common mica, with and without fluorine substitution yielding hydrophobic and hydrophilic substrates. In situ time-resolved Grazing-Incidence Small Angle X-ray Scattering experiments were performed to obtain effective interfacial energy values. Interestingly, the extracted values for both substrates were similar, and thermodynamically these substrates provide a good template for nucleation, but the pathways differ. By ex situ Atomic Force Microscopy characterization, the hydrophilic substrate was shown to promote the formation and stabilization of ACC, whereas the hydrophobic one favored the formation of calcite. These results point to the intrinsic structural flexibility of CaCO3 and its advantage in heterogeneous nucleation processes.The second goal is to provide an atomistic description of the substrate hydrophobicity/hydrophilicity. Water adsorption on phlogopite was studied in situ using Near-Ambient Pressure X-ray Photoelectron Spectroscopy to investigate the effect of fluorine substitution and the influence of different types of counterions (K+, Na+ vs. Cs+). The results of the spectroscopy experiments were further interpreted using molecular dynamics simulations and bond-valence theory. The combination of these techniques shows that the substrate hydrophobicity stems from a competition between two factors: hydration of counterions vs. that of substrate.The final goal is to study the molecular mechanisms by which Mg2+, a common impurity in biogenic amorphous precursors, increases the kinetic persistence of ACC. Inelastic Incoherent Neutron Scattering and X-ray Photon Correlation Spectroscopy were combined to elucidate the nanoscale dynamics of water and ions within ACC. The presence of Mg2+ was shown to enhance the atomic diffusion within the solid while simultaneously increasing the stiffness of the hydrogen bond network. These counter-intuitive results are addressed by considering the different factors included in the pre-exponential term of the nucleation rate equation within the framework of the classical nucleation theory. Overall, the results point to the importance of water as a kinetic stabilizer, and to the existence of steric barriers that lower the crystallization rate
Desmond, Jasmine L. "Investigating the adsorption of select polar functionalities with the aqueous electrolyte/amorphous silica interface to understand the 'low salinity' effect." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/78792/.
Повний текст джерелаDefresne, Alice. "Amélioration de la passivation de cellules solaires de silicium à hétérojonction grâce à l’implantation ionique et aux recuits thermiques." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS533/document.
Повний текст джерелаA-Si:H/c-Si heterojunction solar cells have reached record efficiencies of 24.7%. The passivation of c-Si is the key to achieve a high-efficiency. Indeed, the abrupt discontinuity in the crystal structure at the amorphous/crystal interface induces a high density of dangling bonds creating a high density of defects in the band gap. These defects act as recombination centers for electron-hole pairs photogenerated in c-Si. Several dielectric layers can be used to passivate n-type and p-type wafers: (i) SiO₂ produced by thermal growth, (ii) Al₂O₃ deposited by ALD, (iii) a-SiNₓ:H and a-Si:H deposited by PECVD. The most versatile passivation layer is a-Si: H because it is effective for both p-type and n-type wafers. In addition, this process has a low thermal budget since the deposition is made at 200°C. The drawback of this passivation layer, in particular when p-type doped, is that it does not withstand temperatures above 200°C. However, in order to have a good electrical contact, TCO and metal electrodes require high temperature annealing (between 300°C and 500°C).We implanted Argon ions in solar cell precursors with energies between 1 and 30 keV, which allows to control the depth to which we are creating defects. By varying the fluence between 10¹² Ar.cm⁻² and 10¹⁵ Ar.cm⁻² we control the concentration of defects. We show that implantation with an energy of 5 keV and a fluence of 10¹⁵ Ar.cm⁻² is not sufficient to damage the a-Si:H/c-Si interface. The effective lifetime of the minority charge carriers, measured using a photoconductance technique (decay time of photoconductivity), decreases only from 3 ms to 2.9 ms after implantation. On the other hand the implantations at 10 keV, 10¹⁴ Ar.cm⁻² or at 17 keV, 10¹² Ar.cm⁻² are sufficient to degrade the effective lifetime by more than 85%.Following implantation the solar cells have been annealed in a controlled atmosphere at different temperatures and this up to 420°C. We show that annealing can heal the implantation defects. Moreover, under certain conditions, we obtain lifetimes after implantation and annealing greater than the initial effective lifetime. Combining ion implantation and annealing leads to robust passivation with effective carrier lifetimes above 2 ms even after annealing our solar cell precursors at 380°C. We used a large variety of techniques such as photoconductance, photoluminescence, spectroscopic ellipsometry, Transmission Electron Microscopy, Secondary Ion Mass Spectrometry, Raman spectroscopy and hydrogen exodiffusion to characterize and analyze the physico-chemical phenomena involved in the modification of solar cells precursors. We discuss here several effects such as the increase of the effective lifetime and the temperature robustness by the preservation of hydrogen in amorphous silicon layer and this even after annealing. This hydrogen preservation can be explained by the increase of the number of Si–H bonds in amorphous silicon and the formation of cavities during implantation. In the course of annealing the hydrogen which diffuses is trapped and then released by cavities and dangling bonds, which limits its exodiffusion and makes it available for dangling bonds passivation
ANTOINE, ANNE-MARIE. "Mecanismes de croissance et de constitution d'interfaces dans les couches minces de semiconducteurs amorphes hydrogenes etudies par ellipsometrie spectroscopique in situ." Paris 7, 1987. http://www.theses.fr/1987PA077179.
Повний текст джерелаAwad, Yousef Odeh. "Characterization of amorphous silicon carbide and silicon carbonitride thin films synthesized by polymer-source chemical vapor deposition mechanical structural and metal-interface properties." Thèse, Université de Sherbrooke, 2006. http://savoirs.usherbrooke.ca/handle/11143/1821.
Повний текст джерелаPan, Jie. "UNDERSTANDING ELECTRICAL CONDUCTION IN LITHIUM ION BATTERIES THROUGH MULTI-SCALE MODELING." UKnowledge, 2016. http://uknowledge.uky.edu/cme_etds/62.
Повний текст джерелаMessaadi, Saci. "Modélisation électrique de couches ou de fils minces métalliques : Effet thermique d'interface verre-couche amorphe." Nancy 1, 1987. http://www.theses.fr/1987NAN10048.
Повний текст джерелаOcampo, Juan. "Etude des phénomènes d'interface dans la glace : adsorption, croissance des clathrates et désordre protonique : [thèse en partie soutenue sur un ensemble de travaux]." Grenoble 1, 1988. http://www.theses.fr/1988GRE10087.
Повний текст джерелаLabdi, Yamina. "Caracterisation des structures n+in+ minces, a base de sillicium amorphe hydrogene par la methode des courants limites par charge d'espace : prise en compte des effets d'interface." Paris 7, 1988. http://www.theses.fr/1988PA077091.
Повний текст джерелаSahli, Salah. "Etude du comportement electrique de films minces de gaas amorphes ou polycristallins elabores par depots en phase vapeur ou par plasma a partir d'organometalliques." Toulouse 3, 1986. http://www.theses.fr/1986TOU30049.
Повний текст джерелаKnutson, Christopher C. "The chemistry and device applications of amorphous thin-film interfaces." Thesis, 2011. http://hdl.handle.net/1957/26076.
Повний текст джерелаGraduation date: 2012
Access restricted to the OSU Community at author's request from Dec. 13, 2011 - Dec. 13, 2012
Divya, G. "Structural signatures of relaxation mechanisms in glass forming and devitrifying colloidal suspensions." Thesis, 2023. https://etd.iisc.ac.in/handle/2005/6105.
Повний текст джерелаLin, Yang-You, and 林沇佑. "The Impact on Photovoltaic Efficiency with Regards to Defect Densities of Amorphous Silicon Layers and Carrier Recombination Velocity at Interfaces in a Heterojunction Solar Cell Using Silvaco ATLAS." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/15593378593498140236.
Повний текст джерела大葉大學
電機工程學系
98
This study involves the novel heterojunction with intrinsic thin layer (HIT) solar cell structure. Combining the advantages of both crystalline silicon and amorphous silicon, a new structure of silicon-based solar cell was proposed - the heterojunction with an intrinsic thin layer (HIT) solar cell. It has high stability and large light absorption coefficient. It is manufactured under low temperature deposit process, which results in a low cost thin film HIT solar cell with high conversion efficiency. The influence of various layer materials and interfaces on the performance of n-type c-Si based bifacial HIT solar cell has been investigated by using the Silvaco TCAD simulation software. Accordingly, the design optimization of HIT solar cell was proven.
Lien, Wei-Kuang, and 連偉光. "The influence of p/i interface on hydrogenated amorphous silicon solar cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/13566522814091809944.
Повний текст джерела國立中興大學
電機工程學系所
99
In this thesis, 13.56 MHz plasma-enhanced chemical vapor deposition (PECVD) with pulse-wave modulation of RF plasma is used to fabricate the hydrogenated amorphous silicon (a-Si:H) solar cells. The initial gas concentration is adjusted to control the dissociation of the gases in the plasma and its influence on the performance of solar cells is investigated. The p-layer deposition is controlled by adjusted B2H6 initial-growth gas concentration. The results show that B2H6 flowed into the chamber before the plasma excitation 8 seconds can reduce excessive dissociation of boron atoms on the film surface. The i-layer deposition is controlled by adjusted SiH4 initial-growth gas concentration to increase the dissociation of hydrogen molecules to passivate the dangling bond on the surface of p-layer, which can increase the density of silicon films and reduce the defects on p/i interface. Adjust the initial-growth hydrogen gas concentration can reduce the defects due to oxygen atoms on the p/i interface. Reducing the initial-growth SiH4 gas concentration for i-layer deposition can increase the absorption of short-wavelength photons, but decrease the fill factor and conversion efficiency of solar cells. The initial-growth of i-layer can significantly influence the structure of p/i interface, thus results in the variation of fill factor and conversion efficiency of the a-Si:H solar cells. Control the dissociation of B2H6 of p-layer on the interface between TCO and p-layer and the initial-growth SiH4 of i-layer on p/i interface can effectively improve the fill factor and conversion efficiency.
Yeh, Chun-Cheng, and 葉雋正. "Back Interface Engineering of Amorphous In-Ga-Zn-O Thin Film Transistor." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/70049527206321314667.
Повний текст джерела國立交通大學
光電工程學系
99
With a high mobility (>10 cm2/Vs) and a low threshold voltage (< 5 V) under a low temperature process, transparent amorphous oxide semiconductor thin-film transistors (AOS TFTs) draw considerable attention due to their applications on flexible displays. Beside, a-IGZO is very stable in atmosphere, which makes it an ideal material in sensor technology. In this study, the sensor structure is based on a-IGZO TFT with an additional sensing layer capped above it. a-IGZO active layer is act as electrical transport layer, and the sensing layer can improve sensitivity significantly to diverse bio-chemical molecules. The sensing mechanism might be due to carrier transfer or field effect interaction between sensing layer and a-IGZO active layer under sensing process and influenced by the concentration of specific molecules. This work opens a route to develop low-cost large-area bio/chemical sensor array based on the commercialized a-IGZO TFT technology. Furthermore, we proposed a structure with capping metal layer onto the active layer of bottom-gate a-IGZO TFT to provide a solution to enhance device performance and threshold voltage modulation, which does not cause leakage current degradation. In addition, the device mobility increases significantly after introducing the metal capping layer, and easily oxidized material caused higher mobility in comparison. It is possibly due to variation of oxygen concentration in a-IGZO film causing higher conductivity and carrier concentration in region near the edge and under capping layer assisting carrier transportation. We also propose a defect reduction effect based on reducing weak-bonded oxygen in a-IGZO film. The results enable the development of a-IGZO TFT for the applications like RFID and display driving.
Yi, Yang Chun, and 楊俊儀. "A Study of Interface Between Metal/Amorphous Semiconductor/ Compound Semiconductor and Its Applications for MESFET." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/95373515315744947343.
Повний текст джерела國立成功大學
電機工程研究所
81
The direct coupled field-effect transistor logic (DCFL) which consist of MESFET is widely used for large scale integrated circuit because of its simple circuit and low power dissipation. In addition, MESFET is also an important structure for opto-electrical applications. Unfortunately,the Schottky barrier height between metal and Ⅲ-Ⅴ material is low owing to Fermi-level pinning, this results in low logic swing and makes circuit easily disturbed by noise which limit the work characteristics of MESFET. Recently, the Schottky barrier height is improved by depositing an amorphous material layer which has high energy gap between metal and Ⅲ-Ⅴcompound semiconductor to bring about slow interface state at interface. In this thesis, we deposit three different amorphous materials (a-Si:H, a-SiC:H, a-SiGe:H) between metal (we use Al, Au, Pt) and Ⅲ-Ⅴ smeiconductor and observe the change of Schottky barrier height, reverse leakage current, and breakdown voltage. From experiment,we found that the Schottky barrier height between Au/SiC(200A) is the highest in GaAs and Pt/Si(80A) in InP. In these three amorphous materials, SiC has the least reverse leakage current and the largest breakdown voltage. We use Au/SiC( 500A) as the gate to fabricate field-effect transistor and the transconductance(gm) is 1.5 ms/mm.
Kuo, Jui-Lin, and 郭睿麟. "Interface Improvement Thin-Film Transistors with Amorphous Mg-InGaZnO/InGaZnO AP-PECVD Fabricated Channel Structure." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/2h8m8x.
Повний текст джерела國立交通大學
電子研究所
107
Nowadays, Active-matrix organic light-emitting diode (AMOLED) display applications are toward large size, low power consumption, flexible substrate, high speed and high resolution. Amorphous oxide thin film transistor (AOS) has good electron mobility, process uniformity, low process temperature and high optical transmittance to meet the specifications of next-generation displays. Among many amorphous oxide thin film transistors, IGZO TFT is also competitive with better electron mobility (>10cm2/V-s), small subthreshold swing, large switching ratio (>106) and good reliability. In this paper, the channel layers are all prepared by atmospheric pressure plasma enhanced chemical vapor deposition (AP-PECVD). Because the process is in a non-vacuum system, the cost can greatly decrease, and it is beneficial to large-area manufacturing. Our active layer is double channel structure, 30nm IGZO and 10nm Mg-doped IGZO (Mg-IGZO). The atomic percentage of Mg is 5% of Zn. With subsequent XPS and AFM analysis, this structure can reduce the oxygen vacancy and enhance the metal-oxide bonds strength and the defects between channel with dielectric layer are greatly reduced due to the addition of Mg, which effectively improve the device performance, such as electron mobility, subthreshold swing and switch ratio. Through the comparison of electrical analysis, it was found that using rapid thermal annealing (RTA) is superior to the using furnace annealing in the annealing process and the rapid thermal annealing is a low thermal budget annealing, which is suitable for the application of flexible application. In addition, the faster process time and cost savings of the RTA combined with atmospheric pressure plasma enhanced chemical vapor deposition system can help increase production. In this experiment, the AP-PECVD fabricated amorphous Mg-InGaZnO/InGaZnO channel structure thin-film transistors was successfully fabricated, and the channel layer treated by rapid thermal annealing at 500°C for 30 seconds in O2 ambient was significantly improved. The electron mobility is 16.66 cm2/V·s, the low sub-threshold swing is 83.91 mV/dec, the high switching current ratio is 6.47×107 and the small off current is maintained at about 10-12pA level.
Schuhmann, Henning. "Hochauflösende mikroskopische und spektroskopische Untersuchungen zur strukturellen Ordnung an MgO-CoFeB-Grenzflächen." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9929-2.
Повний текст джерелаFeng, Yu-ting, and 馮宇廷. "The investigation of mechanical properties of ZrCu/Zr/ZrCu amorphous-crystalline nanolaminates with inclined interface by molecular statics simulation." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/90556427491033621712.
Повний текст джерела國立中山大學
機械與機電工程學系研究所
100
In this study, the mechanical properties of Cu-Zr binary bulk metallic glasses (BMG) were investigated at the nano-scale. The stable amorphous structures and corresponding energies of BMG structures are performed by density functional theory (DFT) calculation as reference data. This study will combine the Force-Matching (FM) method and Basin-Hopping (BH) method to develop a new method for fitting the Cu-Zr Tight-binding (TB) potential parameters. Moreover, the Bulk modulus, Shear modulus, Young''s modulus and Poisson ratio of Cu46Zr54, Cu50Zr50 and Cu64Zr36 structures are calculated with the fitting TB parameters. In addition, the compression process of BMG materials is simulated by the Molecular Statics. The stress and strain are obtained to investigate the deformation mechanism of CuZr/Zr/CuZr nanolaminates at 0 and 45 inclined degree. Finally, we investigate the angle in the deformation process under different strain in the shear band, shear transformation zones (STZs) and force caused by the slip of the atomic distribution of TFMGs layer.
Eilers, Gerrit. "Korrelationen zwischen struktureller Ordnung und elektrischen Transporteigenschaften in CoFeB|MgO|CoFeB Tunnelmagnetowiderstandselementen." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B4D9-2.
Повний текст джерелаThiel, Karsten. "Strukturelle Untersuchung der amorph/kristallinen Grenzfläche mittels quantitativer hochauflösender Transmissionselektronenmikroskopie an den Systemen a-Si/c-Si und a-Ge/c-Si." Doctoral thesis, 2006. http://hdl.handle.net/11858/00-1735-0000-0006-B448-6.
Повний текст джерелаWeisemöller, Thomas. "X-ray analysis of praseodymia." Doctoral thesis, 2009. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2009111311.
Повний текст джерела