Дисертації з теми "FABRICATING MONOLAYER"
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1
McCoy, Kendra Michele. "Surface monolayer initiated polymerization a novel means of fabricating sub-100nm features /." Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04122004-094757/unrestricted/mccoy%5Fkendra%5Fm%5F200405%5Fphd.pdf.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Chemical Engineering, Georgia Institute of Technology, 2004.Clifford L. Henderson, Committee Chair ; Peter Ludovice, Committee Member ; Laren Tolbert, Committee Member ; Dennis Hess, Committee Member ; W. Brent Carter, Committee Member. Includes bibliographical references (leaves 119-128).
2
McCoy, Kendra Michele. "Surface Monolayer Initiated Polymerization: A Novel Means of Fabricating Sub - 100 nm Features." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5232.
Повний текст джерелаАнотація:
The speed of microelectronic devices is controlled by the size of the transistor gate. In order to create faster devices, the size of this transistor gate must shrink. Microlithography is the method used to define patterns in semiconductor devices, and it is optimized periodically to create smaller features. It is a subtractive process that relies on the selective removal of sections of a photosensitive polymeric film called photoresist. This photoresist is exposed to patterned ultraviolet radiation that changes the local solubility of the film and allows for the creation of relief patterns in the resist using a developing solvent. Decreasing the wavelength of the light used to expose the patterns is the primary method for decreasing the minimum feature size that can be printed by this process. There are a number of challenges associated with decreasing the exposure wavelength for conventional lithographic processes. First of all, the polymeric films must be transparent at the exposure wavelength in order to allow light to propagate through the entire thickness of the film. Secondly, there is a limit in the thickness of the photoresist films that can be used. This thickness limits the etch resistance of the film. In fact, the issues concerning etch resistance and transparency are generally in opposition. This makes designing photoresist platforms for future lithographic applications very difficult. Therefore, to overcome these limitations, we are developing an unconventional approach to microlithography. In our approach, entitled Surface Monolayer Initiated Polymerization, polymer structures are formed on a surface by polymerizing a monomer in a patterned fashion using a self-assembled monolayer that can be locally activated to initiate the reaction. This process has been demonstrated by creating patterned polystyrene films on native silicon dioxide surfaces. In these initial studies, it took more than one day to create features. This is unacceptable for a lithographic application. The kinetics of all the processes involved in making these patterned layers is described. Along with these rate constants, means of optimizing these rates are also presented. Additionally, the patterns grown in these initial studies exhibited poor uniformity. Methods of optimizing the patterns formed are also presented.
3
Shen, Cai. "Self-assembled monolayers of thiolates as templates for micro/nano fabrication." Thesis, St Andrews, 2008. http://hdl.handle.net/10023/603.
Повний текст джерела
4
Yang, Jeong Hyeon. "Fabrication of gold nanoparticle array on micro-nano structrued self-assembled monolayers." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157582.
Повний текст джерела
5
Maglione, Maria Serena. "Preparation of electro-active self-assembled monolayers for the fabrication of advanced electronic devices." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/565694.
Повний текст джерелаАнотація:
La presente Tesis Doctoral se centra en el estudio del comportamiento conmutable de monocapas auto-ensambladas (SAMs) empleando moléculas electroactivas. Así se realizaron interruptores moleculares cuyo comportamiento fue estudiado en superficies y otros dispositivos tecnológicos. Se emplearon para tales estudios cuatro familias de moléculas electroactivas, las cuales son antraquinonas (AQ), ferrocenos (Fc), tetratiafulvalenes (TTF) y derivados de policlorotrifenilmetano (PTM).
La tesis está estructurada de tal manera que cada capítulo está dedicado a una familia específica de moléculas, estando la primera parte de cada capítulo centrado en la descripción, el diseño y la síntesis de las mismas. Le sigue la fabricación de SAMs en sustratos de óxido de indio y estaño (ITO) u oro, dependiendo de la funcionalidad de la molécula y, finalmente, la integración de moléculas en un dispositivo específico.
Concretamente, monocapas de derivados de PTM y de TTF se fabricaron sobre superficies de ITO y oro, respectivamente. La investigación de sus propiedades de conmutación se llevó a cabo mediante voltamperometría cíclica (CV) usando como mecanismo de lectura la respuesta óptica, magnética y/o de capacitancia. Así, se lograron interruptores moleculares con múltiples estados con alto potencial de aplicabilidad en el campo de dispositivos de memoria.
Además, SAMs mixtas de los derivados de Fc y AQ se fabricaron en sustratos con patrones de ITO // oro logrando sistemas con propiedades confinadas en áreas especificas. El confinamiento de las propiedades superficiales fue comprobado a través de la interacción supramolecular entre β-ciclodextrinas y las diferentes especies redox de las moléculas AQ y Fc.
También, se probó la viabilidad de la integración de SAMs de AQ sobre ITO en dispositivos microfluidicos. La actividad redox de la AQ se utilizó como fuerza motriz en el desplazamiento de gotas de agua, realizando un sistema micro-electro mecánico que funciona a bajo voltaje y, por lo tanto, con alto potencial de aplicabilidad en campos biológicos.
Finalmente, los derivados Fc, TTF y PTM se integraron en transistores de efecto de campo (FETs), funcionalizando el canal activo, el contacto puerata o el dieléctrico.
La presencia de las moléculas electroactivas en las interfaces de los FETs demostró tener un efecto notable en la respuesta de los dispositivos, abriendo nuevas perspectivas para las futuras tecnologías en el campo de la electrónica molecular.The present Doctoral Thesis is focused on the study of the switchable behavior on Surface of specifically designed electroactive molecules by fabricating self-assembled monolayers (SAMs). Subsequently to the study on surface, the molecules were integrated into various devices in order to investigate the effects of the electro-active switch in more sophisticated systems. Four family of electroactive molecules were employed to reach these goals, namely antraquinones (AQ), ferrocenes (Fc), tetrathiafulvalenes (TTF) and polyclorotriphenylmethy (PTM) derivatives. The thesis is structured in such a way that each chapter is dedicated to a specific family of molecules, being the first part of the chapter focused on the description, the design and the synthesis of the molecule of interest. It follows the fabrication of the SAMs on on indiumtin oxide (ITO) or gold substrates, depending on the molecule functionality and, finally, the integration of the molecule in a specific device. SAMs of PTMand TTF derivatives were fabricated on ITO and gold, respectively, and the investigation of their switching properties was carried out by cyclic voltammetry (CV) and using as read-out mechanism the optical, magnetic or capacitance response. In such a way, multi-state molecular switches with high potential in the field of memory devices were achieved. Furthermore,mixed SAMs of Fc and AQ derivatives were fabricated on patterned ITO//gold substrates, where the supramolecular interaction of the different redox species with b-cyclodextrin was used as a proof of the confinement of the surface properties. The feasibility of the integration of electroactive molecules in devices was tested incorporating SAMs of AQ derivatives on specifically designed ITO electrodes in microfluidic chips. The redox activity of the AQ moiety was used as the driving force for the water actuation, realizing a micro electro-meccanical system operating at low voltage and, hence, with high potential in biological fields. Finally, Fc, TTF and PTM derivatives were integrated in field effect transistors, by functionalizing the active channel, the gate contact or the dielectric, respectively. The presence of the electroactive molecules at the FET interfaces was proved to have a remarkable effect on the devices response, opening new perspectives for the future molecule-based technologies.
6
Gardner, Timothy John. "The fabrication and characterization of surface-functionalized microstructures : monolayers as precursors to molecular wires." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12484.
Повний текст джерела
7
Chen, Tao, Rainer Jordan, and Stefan Zauscher. "Polymer brush patterning using self-assembled microsphere monolayers as microcontact printing stamps." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-138826.
Повний текст джерелаАнотація:
Self-assembled microsphere monolayers (SMMs) hold significant promise for micro- and nanopatterning. Here we exploit, for the first time, SMMs as stamps for microcontact printing (μCP) and demonstrate this to fabricate patterned initiator templates that can subsequently be amplified into polymer brushes by surface initiated atom transfer radical polymerization (SI-ATRP). SMM stamps avoid the need for expensive and sophisticated instrumentation in pattern generation, and provide a broad range of accessible surface chemistries and pitch size control.
8
Chen, Tao, Rainer Jordan, and Stefan Zauscher. "Polymer brush patterning using self-assembled microsphere monolayers as microcontact printing stamps." Royal Society of Chemistry, 2011. https://tud.qucosa.de/id/qucosa%3A27784.
Повний текст джерелаАнотація:
Self-assembled microsphere monolayers (SMMs) hold significant promise for micro- and nanopatterning. Here we exploit, for the first time, SMMs as stamps for microcontact printing (μCP) and demonstrate this to fabricate patterned initiator templates that can subsequently be amplified into polymer brushes by surface initiated atom transfer radical polymerization (SI-ATRP). SMM stamps avoid the need for expensive and sophisticated instrumentation in pattern generation, and provide a broad range of accessible surface chemistries and pitch size control.
9
Chesnau, Frédérick [Verfasser], and Michael [Akademischer Betreuer] Zharnikov. "Fabrication of Metal-Insulator-Metal assemblies for spintronic devices using self-assembled monolayers / Frédérick Chesnau ; Betreuer: Michael Zharnikov." Heidelberg : Universitätsbibliothek Heidelberg, 2011. http://d-nb.info/1180545710/34.
Повний текст джерела
10
Lakbub, Jude. "Fabrication of Chemically Modified Nanometer-sized Gold Electrodes and Their Application in Electrocatalysis at Pt Nanoparticles." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1385.
Повний текст джерелаАнотація:
Hydrogen evolution via proton reduction occurs at a high rate at the surface of Pt than at Au electrodes. Using cyclic voltammetry, chemically modified nanometer-sized Au electrodes, prepared by the Laser-Assisted Puller Method, were employed to examine current amplification by electrocalysis at Pt nanoparticles adsorbed on the modified Au electrode surfaces. The electrodes were modified with Self-Assembled Monolayers (SAMs) of cysteamine and soaked in Pt colloid solutions overnight. Monitoring the decrements of the characteristic steady-state catalytic current for proton reduction indicated that aggregates of Pt nanoparticles are adsorbed on the cysteamine monolayers and desorb from them particle by particle. The results also indicate that some particles are strongly attached to the modified electrode surface and do not deplete even after thorough rinsing.
11
Hajlaoui, Riadh. "Effet de la structure sur les propriétés électriques et optiques d'oligomères conjugués semi-conducteurs. Application à la réalisation de transistors à effet de champ et de diode électroluminescentes." Rouen, 1995. http://www.theses.fr/1995ROUES005.
Повний текст джерелаАнотація:
L'étude structurale des polymères conjugués montre que leur désordre moléculaire et structural limite la qualité de leurs propriétés électroniques, et restreint donc leur éventuelle application à des composants électroniques. L'utilisation de systèmes moléculaires structuralement bien définis devrait par contre permettre de s'affranchir de ces défauts chimiques et physiques, et d'améliorer ainsi l'efficacité du transport de charges dans ces matériaux semi-conducteurs. Cette démarche est illustrée ici par l'étude du sexithiophène (6T) et de ses dérivés substitués. La première partie est consacrée à la description des techniques expérimentales de préparation des films minces, puis des composants électroniques réalisés à partir de ces semi-conducteurs organiques, tels que transistors à effet de champ en couche mince et diodes électroluminescentes. L'étude des propriétés structurales et optiques a mis en évidence que ces films sont polycristallins, et que l'orientation des chaînes moléculaires sur le substrat est contrôlée par la nature du substrat, par la température de dépôt et par la position de substitution de groupes alkyles sur cette molécule (6T). Les mesures de conductivité et de mobilité d'effet de champ du sexithiophène et de ses dérivés montrent que pour le , -dihexyl-sexithiophène, la conductivité présente une anisotropie importante, alors que b,b'-dihexyl-sexithiophène se comporte comme un isolant. La température du substrat utilisée lors du dépôt du film influe sur la conductivité et sur la mobilité du sexithiophène. La mobilité plus faible de 6T à température ambiante est attribuée à une plus grande concentration de défauts tels que joints de grains. Les caractéristiques statiques des diodes électroluminescentes, dont les couches actives sont constituées de sexithiophène ou de l'un de ses dérivés, montrent un effet redresseur (semi-conducteur de type-p). Les caractéristiques transitoires montrent un courant capacitif bref, suivi d'un courant permanent donnant lieu à émission lumineuse. Dans une structure bicouche, on remarque une augmentation de l'émission lumineuse et une augmentation du rendement d'électroluminescence par rapport à la structure monocouche. L'intensité du spectre d'électroluminescence enregistré pour la structure bicouche dans la gamme 500-700 nm montre qu'en baissant la température l'émission augmente, ceci est attribué à une diminution du rendement des transitions non radiatives
12
KAKOTY, NIMISHA. "SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF MOLYBDENUM DISULFIDE NANOSHEET." Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14871.
Повний текст джерелаАнотація:
The search for monolayer materials to substitute silicon in electronic devices has widened in the past decade. Despite the benefits of two dimensional graphene, it has no band gap and behaves as a semi-metal. Molybdenum disulphide is a promising material as it boasts a band gap of up to 1.9eV in a monolayer form. In this project, an inexpensive method of fabricating monolayer MoS2 is designed and growths on Si-substrates for future use in electronic devices will be attempted with this fabrication method
13
Li, Hsuan-De, and 李宣德. "Fabrication of multilayer and monolayer graphene devices." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/74261588473944922097.
Повний текст джерелаАнотація:
碩士中原大學
物理研究所
98
Graphene has emerged as an exciting material because of the novel properties associated with its special two-dimensional structure. Due to its special band structure, graphene has observed an abnormal half-integer quantum Hall effect. We would like to fabricated the graphite sheets (multilayer or monolayer graphene) and than to made devices for studying quantum transport. We have made graphene by two methods, micromechanical cleavage and longitudinal unzipping of carbon nanotubes. The first method is the cleavage of the graphite with the tape to produce the graphene. This 3M scotch-tape is better in a variety of tape, and it is relatively apt to make graphene under the environment of low-temperature and low-humidity. The second method is by using KMnO4/H2SO4 to cause the chemical reaction for longitudinal unzipping of carbon nanotubes to make graphene nanoriboons, and than transfer graphene nanoribbons on SiO2/Si substrate. By checking on the optical microscope, we can find the graphite or few layer graphene. The thickness is distinguished of the graphite sheets from the color of image. And also analyzed the Raman spectrum and Atomic force microscope (AFM) of graphene, and determine the number of graphene layers. In the future work, first, the weak localization effect will be studied for quantum interference in graphenes. Second, the graphenes will be fabricated for studying spin electronics.
14
孫介偉. "Fabrication of Nanometer Scale Self-Assembled Monolayer Devices." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/05071359390456759302.
Повний текст джерела
15
Chang, Hsuan-chun, and 張亘鈞. "Fabrication of TCO on Self-Assembled Monolayer Modified Glass." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/85599557965519861587.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
98
In this work, we studied the deposition of ITO and AZO on self-assembled monolayer (SAM) modified glass substrate with RF sputtering. In general , deposition of ITO and AZO thin films under low temperature condition result in the amorphous or less crystallinity structures, which needed to be improved by post annealing of thin film at high temperature. However, in this study, we have found that high crystallinity can be achieved in low temperature by modification of glass substrate by SAMs prior to ITO and AZO deposition.The ITO with high electrical conductivitycan be fabricated by using –SH SAM modified glass substrate. We attributed the improvement of electrical conductivity to larger quantity of Sn atoms attached on thiol functional group. In addition, for the deposition of AZO, the surface tension of glass substrate was modulated by fabrication of SAMs with different functional groups, which the preferential growth direction of AZO thin film could be controlled to along c-axis or a-axis.
16
Jia-XingWu and 吳家興. "Fabrication of Thiol Monolayer Functionalized Schottky-type NOx Sensors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/49fuw8.
Повний текст джерелаАнотація:
碩士國立成功大學
化學工程學系
106
In this work, we devoted to fabricate the NOx sensor based on Au/InGaP Schottky diode. In order to enhance NOx selectivity and sensing response, self-assembled monolayer (SAM) – dithiol was used for modifying the Schottky contact because of its self-assembled property and particular functional group. The effect of SAM immersion time (t=1,6,12,24,36,48,60h) and carbon number of SAM (n=3,6,9,10,11,16) has been comprehensively discussed in our research. In addition, the selectivity and sensing performance of dithiol modified Au/InGaP Schottky diode in different temperature and NOx concentration has been researched. With a view to fabricating the best NOx sensing performance Schottky diode, cyclic voltammetry is applied to simulate the thiol monolayer self-assembled on Au surface and its amount is also further calculated by reduction peak current analysis. At the end of this study, the first order kinetic and thermodynamic model has been fitting successfully with NOx sensing results.
17
Chen, Lian-Hua, and 陳斂樺. "Fabrication of Gold Nanoparticles LB Films by Templating Langmuir Monolayer." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/75549242425829011061.
Повний текст джерелаАнотація:
碩士國立成功大學
化學工程學系碩博士班
94
Gold nanoparticles (Au NPs) were prepared and surface modified by mercaptosuccinic acid (MSA) to render a surface with carboxylic acid groups (MSA-Au). Octadecylamine (ODA) was used as a template monolayer to adsorb the Au NPs dispersed in subphase. The effects of MSA concentration on the incorporation of MSA-Au to the ODA monolayer and the relevant behavior of the mixed monolayer are studied by the pressure-area (π-A) isotherm and by the observation of transmission electron microscopy (TEM). The experimental results show that the adsorbed density of Au NPs is low without the surface modification of MSA. When MSA was added into the Au NPs containing subphase, the incorporation amount of gold particles increases with increasing concentration of MSA up to about 1 x 10-5 M for the particle density 1.3 x 1011 particles/ml. With further increase of MSA concentration, the adsorbed particle density decreases due to the competitive adsorption between the free MSA molecules and the MSA-Au NPs. It is inferred that that free MSA molecules are more easily to adsorb, than the MSA-Au NPs, to the ODA monolayer. Therefore, an excess amount of MSA presented in the subphase is disadvantageous to the incorporation of gold particles. The study on the monolayer behavior also exhibits that the π-A isotherm of ODA monolayer shifts right when little amount of Au NPs or free MSA molecules are incorporated. However, when higher amount of particles are adsorbed at the air/liquid interface, a left-shift of the π-A isotherm appears probably due to the adsorption of MSA molecules onto the particles surface and the transferring of the particles from beneath the ODA monolayer to the air/water interface. According to the present method, it is able to prepare uniform particulate film of controlled density through the controlling of particle concentration in the subphase, the MSA concentration, and the compression of monolayer. Next, we replaced the ODA monolayer with PDPA polymer as template to adsorb the gold nanoparticles of subphase. PDPA polymer spread at interface as template is the same of ODA monolayer to adsorb gold nanoparticles capped MSA molecular by electrostatic interface to obtain the organic/inorganic mixed film improving the application of polymer.
18
Chiou, Tz-Chen, and 邱子宸. "Fabrication and characterization of monolayer MoS2 nanosheet transistor for VLSI applications." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f3zq2t.
Повний текст джерела
19
Huang, Wei-Ping, and 黃偉萍. "Monolayer WSe2 field effect transistor：Device fabrication and bias dependent optical properties." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/7w23j7.
Повний текст джерелаАнотація:
碩士國立交通大學
電子物理系所
103
We investigate the device fabrication and photoluminescence properties of monolayer tungsten diselenide (WSe2) field-effect transistor (FET). The WSe2 monolayers were grown on sapphire substrates by chemical vapor deposition (CVD), and then transferred onto SiO2/Si substrates for fabricating back-gate FETs. In CVD growth, we found that introducing hydrogen (H2) plays a key role in the WSe2 growth, in addition to the growth temperature, pressure and W/Se ratio. A suitable amount of H2 could efficiently reduce the defect densities and improve the emission properties. The fabricate back-gate FETs show p-type characteristics, with high current on/off ratios. The FET performance can be further improved by thermal annealing processes at relative low temperatures. Then, we investigate the effects of gate-control carrier doping on the emission properties of WSe2 monolayers. With the applied gate voltage, PL peaks of charged excitons can be observed at the low energy side of neutral excitons, by which the binding energy of both positive and negative charged excitons can be determined. Moreover, we found that the PL emission of defect-bound excitons could be suppressed by applying a negative gate voltage, indicating that the defects are mostly acceptor-like. Finally, we investigate the gate-dependent valley polarization and coherence, which could be helpful in developing WSe2 for future valleytronic application.
20
Tsai, Meng Shiun, and 蔡孟訓. "Fabrication of bacteriorhodopsin photoelectric chips with self-assembled monolayers." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/19470997224065160710.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
99
Purple membrane (PM) is part of the cell membrane of archaeon Halobacterium salinarum, where bacteriorhodopsin (BR) resides as the major protein and acts as a light-driven proton pump. In this thesis, self-assembled monolayers (SAM) formed by carboxyalkylphosphonic acids were employed to fabricate ITO glass, followed by amination to subsequently immobilize PM through bioaffinity interactions. The layer-by-layer coating was confirmed by both contact angle and cyclic voltammetry measurements, with the observation of variation of contact angles from 3~5° on ITO, up around 75° on the SAM layer, and finally down to 20~30° on PM, and of decrease of redox peak-currents of the electrode with increased coating layers. The coating was also confirmed by XPS analyses. The photocurrent responses of the PM-coated chips strongly depended on the buffers to suspend PM and to post-wash chips and on the pHs of the measuring electrolyte, with the achievement of a maximum photocurrent density of 1.1±0.1 μA/cm2. Both AFM and XPS analyses suggested the coating amount and morphology of PM on ITO glass significantly affected the photoelectric performance of the prepared chips. Finally, delipidation of the immobilized PM with a SDS flow resulted in BR unfolding and refolding and in PM displacement and reorganization. About 30% of the chip-photocurrent activities were recovered, demonstrating the robustness of the prepared PM-coated chips and suggesting the PM potential for future applications in DSSC and biochips.
21
廖均恆. "Investigation and fabrication of self-assembled monolayer nano-transistor with three electrodes." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/26431769854028866134.
Повний текст джерела
22
Ho, Yu-Hsuan, and 何雨璇. "Study the Fabrication of AZO Films on Self-Assembled Monolayer Modified Glass." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/c9aua4.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
100
In this work, we studied the deposition of AZO on self-assembled monolayer (SAM) modified glass substrate with RF sputtering. In general , deposition of AZO thin films under low temperature condition result in the amorphous or less crystallinity structures, which needed to be improved by post annealing of thin film at high temperature. However, this way will substantially increase production costs. In this study, we have found that high crystallinity and low resistivity can be achieved in room temperature by fabricating AZO thin films on long chain length SAM modified glass substrate. In addition, for the deposition of AZO, the surface tension of glass substrate was modulated by fabrication of SAMs with different wettability, which the preferential growth direction of AZO thin film could be controlled to along c-axis or a-axis.
23
Han-WenChan and 詹涵雯. "Fabrication of P3HT/Gold Nanoparticles LB Films by P3HT Templating Langmuir Monolayer." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/91485576767826224805.
Повний текст джерелаАнотація:
碩士國立成功大學
化學工程學系碩博士班
98
Regioregular poly-(3-hexylthiophene)(rr-P3HT) and mixed P3HT/ octadecylamine(ODA) was used as template monolayers to adsorb the gold nanoparticles (AuNPs) dispersed in subphase. Furthermore, the adsorption of AuNPs was enhanced by the destabilization effect of ethanol and CaCl2 introduced into the colloidal solution. The behaviors of the P3HT/AuNPs mixed films were studied by the pressure-area (π-A) isotherm and by the observations of transmission electron microscopy (TEM) and atomic force microscope (AFM). The experimental results show that P3HT do not form a homogeneous monolayer and tends to aggregate at the air/liquid interface. Meanwhile, the AuNPs adsorbed by the P3HT monolayer are low, attributable to the short interaction distance between AuNPs and P3HT. The introduction of ethanol and CaCl2 into the colloidal solution can increase the adsorbed amount of AuNPs, decrease the aggregation structure of P3HT, and leads to a more homogeneous P3HT/AuNPs monolayer. In addition, the introduction of ODA in the P3HT monolayer can also decrease the aggregation of P3HT molecules and enhance the incorporation of AuNPs into the monolayer.
24
fu-long, lin, and 林福龍. "Study Self-Assembled Monolayer on Silicon-Pattern Fabrication and Chemical Sensor Application." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/36880848580706936439.
Повний текст джерелаАнотація:
碩士國立交通大學
材料科學與工程系
91
In recent research reports, self-assembled monolayer (SAM) has been studied in many filed , especially in molecular device、nanodevice and biotechnology. As we know many applications in electronic, chemical or biosensor, display, or biochip almost requires the two-dimensional pattern for different substrates. Therefore how to pattern the SAM, especially the feature size down to sub-micron or nano-scale, would become a more and more important direction for the future. The alkyl silane and aromatic silane are typical used as nanoresist for SAM application, such as Octadecyltrichlorosilane (OTS) and Octyltriethoxysilane(OTES) in this thesis studying. The SAM’s resist usually has a good pattern transfer property after developed. Because it is thinner than typical polymer resist and it’s also suitable used in nanolevel lithography. On the other hand, the terminal with amino or hydroxyl groups of SAM are often used as linker (or precursor)for bonding or absorbing the biomolecular 、nanoparticle、or carbon nanotube….etc, such as 3- Amino-propyl triethoxy silane(APTS) in this thesis studying. But the packing density and structure (monolayer or sub-monolayer) of SAM on silicon may have variety changes by different conditions of prepared mode and surroundings, especially it may stronger effecting used as resist for application. Due to that, in this thesis, we firstly focus on choosing the different prepared mode by self-assembly OTS on silicon and compare the OTES using the chemical etch to test their packing density and also study the reliability for the resist application. And finally we will also discuss the prepared mode and analysis of APTS. The second part we will focus on using the E-beam writer and Scanning Probe Microscopy (SPM) lithography to pattern the SAM. After the pattern transfer, it will further selectively immobilize APTS and gold nanoparticle on the pattern region. In this part, the sub-micron to nanoscale pattern of gold nanopareicle has been developing. Integrated the above techniques on our design thin film transistor (TFT) for pH sensor was in the third part. The tail of amino group of APTS, it’s behavior exhibit like pH-dependent conductance that change when surface charge during protonation and deprotonation in solution. In the other hand, the Alkyl silane is used as the resist and modifies on sensor surface (except channel) for isolating the charge affecting and further pattern the APTS and gold nanoparticle. Using the SPM lithography create 2-D patterns on TFT device, the result is not well. Because the substrate must be conductor or semiconductor by this way, but there is a insulator to effect oxidation on device, so it only see some mechanical scrape the monolayer, resulting the APTS packing density on poly-Si channel is very weaker and further effecting the gold nanoparticle absorb on poly-Si surface. Therefore the pH —sensor fabricate, in here, it is direct modify of APTS and gold nanoparticle on overall device. But there are very random results of electricity measurement by different pH detection. There are many factors may possibility effecting of the detection. But the dimension and structure of device and measurement may stronger effect the pH detection and it’s also more than surfaces modify the SAM effecting of our discussion. But we also learn something in this study, like prepare and analyze the SAM, and using the SPM or E-beam techniques pattern the monolayer, electronic device measurement, and design of electronic device.
25
Zena, Desalegn Manayeh, and Desalegn Manayeh Zena. "Hybrid Polymer Solar Cells: Self-Assembled Monolayer Assisted Fabrication of ZnO Nanostructures, Surface Modification and Device Fabrication." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/78352470891245176544.
Повний текст джерелаАнотація:
博士國立臺灣科技大學
化學工程系
101
In this study, zinc oxide (ZnO) nano-rods were fabricated on self-assembled monolayer (SAM) modified ZnO seeded indium oxide (ITO) substrates. By changing the tail group and growth time of SAM, the nano-rod thickness, diameter as well as optical properties can be controlled effectively. X-ray diffraction patterns confirmed that, with the optimized growth conditions, the nano-rods are highly crystalline with (002) preferred orientation, which are desirable for solar cell application. With optimized nano-rods, hybrid polymer solar cells based on ZnO nano-rod/ poly (3-hexylthiophene) (P3HT) were fabricated. We employed benzoic acid (BA) and C60-propandioic acid (CPA) individually as modifier in the interface of ZnO nano-rod/ P3HT. It is revealed that the short-circuit current (Jsc) of the device can be improved significantly by applying the CPA-SAM, while the BA-SAM enhanced the open circuit voltage (Voc). Mixing-SAMs of CPA and BA in different compositions can improve the Jsc and Voc simultaneously. The power conversion efficiency improved from 0.31% for the device without SAM modification to 0.73% with the interfacial modification using mixing-SAMs in optimized ratio. We attribute the improvement in conversion efficiency to higher charge separation ability and carrier mobility of CPA-SAM and the work function modulation of ZnO surface by the BA-SAM.
26
Lin, Sheng-wei, and 林聖為. "Coupling of self-assembled monolayer and bioaffinity adsorption to improve purple-membrane chip fabrication." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/ckaek6.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
100
Bacteriorhodopsin residing in the purple membrane (PM) of Halobacterium salinarum can generate photoelectric responses after being illuminated. In this study, different self-assembled monolayer (SAM) molecules as well as immobilization methods were employed to optimize the fabrication process of PM chips and to control the orientation of immobilized PMs. The contact angles of ITO varied with the lengths of coating carboxyalkylphosphonic SAMs, with 16PHDA yielding the most hydrophobic surface (～90°) and 3PPA the most hydrophilic one (10-20°). In CV analyses, the oxidation and reduction peak currents of 16PHDA-coated ITO were -37 and 34 μA, respectively, with both values increasing with the SAM length and reaching to -43 and 43μA, respectively, for 3PPA. In addition, PM bioaffinity-immobilized on longer carboxyalkylphosphonic SAM-coated ITO was wedge-shaped in appearance as revealed by AFM analyses, yielding higher differential photocurrents and longer decay time of the B2 pulse photocurrents than the PM coated on shorter SAMs. Polar solvents favored the adsorption of 6PHA on ITO through its phosphonic end, and the coating amount of PM on an aminophosphonic SAM, APPA, was higher than that on its length-equivalent carboxyalkylphosphonic SAM, 3PPA. Furthermore, the surface morphology and roughness of ITO had effects on the coating and differential photocurrent response rate of coated PM. Moreover, PM covalently immobilized on 16PHDA-coated ITO was orientated with its cytoplasmic side facing ITO no matter the coating conditions. The papain-digested PM generated higher photocurrents than the undigested one when coated with pH 4.5 and 7 suspension buffers, while the results were vice versa when a pH 5.2 buffer was used. Compared to affinity immobilization, the covalent method led to a much less coating amount and more stretching of PM; however, both methods yielded the same PM orientation.
27
Yu-LinHsiao and 蕭裕霖. "Fabrication of Graphene Oxide Monolayer by Langmuir-Blogett Technique and Its Application on Glucose Biosensor." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/33483753812572750655.
Повний текст джерелаАнотація:
碩士國立成功大學
化學工程學系
103
In order to prepare graphene oxide (GO) and glucose oxidase (GOx) monolayer, we functionalize the graphite with oxidize agent by modified Hummer’s method. Moreover octadecylamine (ODA) monolayer was used as a template to adsorb GO and GOx from solution to air/water interface by interactions between the template and GO or GOx. We study the behavior of the GO/ODA and GOx/ODA mixed monolayer at air/water interface by pressure-time (π-t) isotherm and the pressure-area (π-A isotherm) isotherm. The morphology of the GO/ODA LB film was examined using Transmission electron microscope (TEM) and Atomic force microscope (AFM). In order to regain the film conductivity, we expose the GO/ODA LB film under UV light to form Reduced Graphene Oxide (rGO). Then the GO and rGO monolayer were dipped on the platinum for biosensors fabrication to study electrochemical property and to get the sensor sensibility. According to experiment results, GO can be adsorbed by surfactant on air/water interface and form GO monolayer. The surface coverage and morphology of the monolayer on the air/water interface can be controlled by surface pressure. From the electrochemical experiment, rGO which reduced by UV light has better electrochemical activity. It shows the best sensing ability to hydrogen peroxide when dipping 3 layers of rGO on the substrate. Moreover the glucose sensor exhibits the highest sensitivity(5.808 μA/cm2∙mM).
28
Tsai, Hui-Jung, and 蔡惠榕. "Fabrication of Nanoparticulate Monolayers by using Langmuir-Blodgett and Self-Assembly Techniques for Superhydrophobic Surface." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/40495496481385559821.
Повний текст джерелаАнотація:
博士國立成功大學
化學工程學系碩博士班
97
Nanoparticulate monolayers were prepared by using Langmuir-Blodgett and self-assembly techniques and used for superhydrophobic surface application. Langmuir monolayers of octadecylamine (ODA), octadecylthiol (ODT), and mixed ODA/ODT at air/liquid interface were used as template layers to adsorb gold nanoparticles (AuNPs) dispersed in the subphase. Furthermore, the adsorption of AuNPs was also enhanced by the destabilization effect of ethanol introduced into the colloidal solution. The monolayer not only acts as a template layer to incorporate AuNPs but also as a capping agent to in-situ modify the adsorbed NPs, providing van der Waals interaction among NPs for self-organization into ordered domains. The behaviors of the monolayers were studied using the pressure-area (π-A) isotherms, hysteresis and relaxation curves, and the observations of transmission electron microscopy (TEM) and Brewster angle microscope (BAM). For the ODA/AuNPs and ODT/AuNPs systems, the results indicated that ODA monolayer has a much higher ability, than the ODT monolayer, in incorporation AuNPs, attributed to the electrostatic interaction between ODA and AuNPs. By using ODA monolayer with appropriate molecular density, as well as the adjusting of the ethanol concentration, a close-packed particulate film of AuNPs can be prepared through the monolayer compression. The results also show that over loading of the ODA molecules increases the fractional ratio of free ODA molecules at the interface which obstructs the coalescence of particulate domains and, therefore, a close-packed particulate monolayer cannot be approached. The presence of ethanol in the subphase not only enhances the particle adsorption to the interface but also triggers a more expanded ODA monolayer, which plays a key role in preparing a close-packed particulate monolayer. For the mixed ODA/ODT systems, the incorporation of AuNPs was mainly performed by ODA molecules through the electrostatic interaction, while the specific affinity of ODT molecules to the AuNPs plays a role to increase the density of capping agents on an AuNPs, leading to a higher van der Waal interaction among NPs for self-organization into ordered domains. The experimental results showed that the utilization of the mixed ODA/ODT monolayer can improve the stability of AuNPs incorporated at the air/liquid interface and is helpful to the formation of an AuNPs particulate film with close-packed and ordered structure. For the application of particulate thin films on surperhydrophobic surface, a micro/nano dual-scale particulate film with raspberry-like morphology was prepared by using LB deposition and electrostatic layer-by-layer (ELBL) technique. Micro-size silica particles were used to prepare a surface with microscale roughness. Nano-size silica particles were then assembled on the particulate film to construct a finer structure on top of the coarse one. The as-deposited particulate films were surface-modified with alkylsilane to render a surface with surperhydropboic property. The advancing and receding contact angles of water on the dual-size structured surface were 169o and 165o, respectively. The scale ratio of the micro/nano surface structure and the regularity of the particulate films on the superhydrophobic surface performance are discussed.
29
WU, YI-CHIEH, and 吳怡潔. "Study the Fabrication of Molybdenum Thin Films on Self-Assembled Monolayer Modified Glass Substrate by DC Magnetron Sputtering." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/77173351442008803990.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
101
In general, molybdenum thin film can be used as an electrode in CIGS or CZTS solar cells device. High power and high temperature condition is conducive to better crystallinity and resistivity, but it required numbers of energy and is not suit for flexible substrate. In this work, we studied the deposition of molybdenum thin film with DC magnetron sputter on soda lime glass substrate modified by self-assembled monolayer (SAM). First, we sputtered molybdenum on soda lime glass substrate which was not modified to find the optimization parameters. Basing on these parameters, we use SAMs to modify the soda lime glass substrate to get better crystallinity and lower resistivity of molybdenum thin films. Sputtering the molybdenum thin films at room temperature on soda lime glass substrate modified by –SH and -COOH SAMs can increase the mobility because of chemical bonding between molybdenum and SAMs. In order to observe the changing of the carrier mobility of molybdenum thin films, we control the concentration of –SH and –COOH SAMs. At last, the mobility and carrier concentration could be adjusted by changing the ratio of mixing COOH- and CF3- SAMs.
30
Lin, Meng-Hsien, and 林孟賢. "Plasma Modification of Self-Assembled Monolayers for Chemical Patterning and Fabrication of Large-Area 3D Plasmonic Supercrystals." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/34801414462583826120.
Повний текст джерелаАнотація:
博士國立清華大學
奈米工程與微系統研究所
99
Nanotechnology has been developed as a reliable technology for producing minimal components to perform more precise functions. In particular, the availability of nanolithography and nanostructure fabricating processes is important in the fields of photonics, electronics, biotechnology, and metamaterial. In our research, we present a generic and efficient chemical patterning method, compared with conventional photolithography this approach is without diffraction limit. Base on this approach, we expand a method for synthesizing three-dimensional (3D) gold and silver nanoparticle supercrystal films. Since nanoparticles have unique properties of surface plasmon, this technology will offer a pathway to designer plasmonic metamaterials. We fabricate chemical pattern based on local plasma-induced conversion of surface functional groups on self-assembled monolayers. Here, spatially controlled plasma exposure is realized by elastomeric poly(dimethylsiloxane) (PDMS) contact masks or channel stamps with feature sizes ranging from nanometer, micrometer, to centimeter, and an achievable resolution is down to the 50 nm range. This chemical conversion method has been comprehensively characterized by a set of techniques, including contact angle measurements, X-ray photoelectron spectroscopy (XPS), scanning photoelectron microscopy (SPEM), scanning electron microscopy (SEM), and scanning Kelvin probe microscopy (SKPM). In particular, XPS and SPEM can be used to distinguish regions of different surface functionalities and elucidate the mechanism of plasma-induced chemical conversion. Based on plasma-induced conversion, we expand a simple and efficient method for synthesizing large-area (>cm2), three-dimensional (3D) gold and silver nanoparticle supercrystal films. In this approach, Janus nanoparticle (top face solvent-phobic and bottom face solvent-philic) films with an arbitrary number of close-packed nanoparticle monolayers can be formed by using layer-by-layer (LbL) assembly from suspensions of thiolate-passivated gold or silver colloids. Furthermore, we demonstrate that these films can act as true 3D plasmonic crystals with strong transverse (intralayer) and longitudinal (interlayer) near-field coupling. In contrast to conventional polyelectrolyte-mediated LbL assembly processes, this approach allows multiple longitudinal coupling modes with a conspicuous spectral dependence on the layer number. We have found a universal scaling relation between the spectral position of the reflectance dips related to the longitudinal modes and the layer number. This relation can be understood by the presence of a plasmonic Fabry-Pérot nanocavity along the longitudinal direction, allowing the formation of standing plasmon waves under plasmon resonance conditions. The realization of 3D plasmonic coupling enables broadband tuning of collective plasmon response in a wide spectral range (visible and near-infrared) and a key pathway to designer plasmonic metamaterials.
31
Lin, Po-Fan, and 林柏帆. "The fabrication of nanodiamond microarray chip by self-assembled monolayer technology：The optical measurement of coupled gold nanoparticles on microarray chip." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/91364082524239950833.
Повний текст джерелаАнотація:
碩士國立交通大學
應用化學系所
98
Recently, nanodiamond has become one of the best candidates to serve as a biobinding platform due to its special properties such as, high chemical stability, good photo-stability, easily surface modification, and binding affinity with biomolecules. In the first part of this thesis, we used E-Beam lithography system to design patterned nanostructure arrays. By using self-assembled monolayer (SAM) technology, we were able to position nanodiamonds into regular arrays on the silicon substrate and to fabricate a nanodiamond microarray chip. In the second part of this work, we bound the nanodiamond surface with two complementary DNA sequences and gold nanoparticles. After the gold nanoperticle hybridize on the nanodiamond microarrays, we measured the micro-PL spectrum of nanodiamonds through a confocal microscope. In the spectrum, we observed enhancement of the PL signal of the nanodiamonds after hybridization, which demonstrated that the gold nanoparticles have modfied the optical signal from the nanodiamonds. In the future, the signal will be used as an index for biosensing purposes.
32
Lin, Kai-Siang, and 林楷翔. "Study of Low Temperature Alumiminum-induced and Self-assembled Monolayer-assisted Fabrication of Polycrystalline Silicon – the Effect of 3-aminopropyltriethoxysilane." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/h7k6h4.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
105
In this research, we focus on how to transfer amorphous silicon (a-Si) to poly-crystalline Si (poly-Si). There are many methods to fabricate poly-Si on glass substrate. Chemical vapor depostition can directly deposit poly-Si on heterogeneous substrate. Solid phase crystallization (SPC), Excimer laser crystallization (LC), Metal induced crystallization (MIC) can recrystallize a-Si film to poly Si film by giving secondary energy. These methods usually need much high process temperature. In this decades, application on soft materials has already been a big issue. In order to fabricate poly-Si film on soft board, it is necessary to decrease the process temperature. In our approach, we use aluminum induced crystallization method. By improving the quality of a-Si film with hydrogen or using self-assembles momolayers with different functional group to modify the surface tention and polarity of the substrate prior to the deposition of silicon, the process temperature may decrease to the temperature which soft board can endure. In this study, we find that the substrate modified by aggregate APTES-SAM has some effects. After Si atoms deposite on the modified substrate by RF-sputterin, there comes some covalent bonding like Si-O-Si or Si-N-N-Si. And the follow up Si atoms will grow near these seed crystal sites. Without capped with aluminum and annealing process, it can grow up poly-Si in partial region. Although this kind of Si film can not called a poly-Si film because there still exists some amorphous regions in the film, we try to figure out this phenomenon and give a reasonable explains.
33
Lin, Che-Yu, and 林哲宇. "Fabrication of platinum electrodes on transparent conductive glass by electrochemical deposition and surface modification of self-assembled monolayers." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/39458332276985459951.
Повний текст джерелаАнотація:
博士國立清華大學
化學工程學系
100
In this study, we aim to develop a simple, low temperature process to fabricate the Pt counter electrodes for dye-sensitized solar cells (DSSCs) based on electrochemical deposition techniques including electroless deposition (ELD), electrodeposition (ECD) and surface modification of self-assembled monolayers (SAMs). By electroless deposition, a cost-effective and low- temperature wet process to coat Pt on counter electrode has been developed with superior coating selectivity by means of self-assembly monolayers modification and electroless deposition techniques. Images of fluorescent test and atomic force microscope measurements demonstrated that 3-(2-Aminoethylamino) propylmethyl- dimethoxysilane (Me-EDA-Si) was homogeneously grafted on FTO surface and XPS result proves that the palladium deposited on the FTO surface initiates the electroless deposition. The Pt deposit so obtained exhibits rough morphology and increased active sites. This method makes it easy to deposit a Pt thin-film under ambient condition without the need for high vacuum chamber. Moreover, the so-prepared DSSC exhibits improved performance compared to the DSSC with a sputtered Pt counter electrode. In the case of electrodeposition, Pt counter electrodes with low charge-transfer resistance (Rct), low Pt loading and high active surface area can be obtained within 30s by using the direct-current deposition in the presence of 3-(2-Aminoethylamino) propyl -methyldimethoxysilane (Me-EDA-Si) as an II additive. The addition of Me-EDA-Si can not only enhance the current efficiency but also inhibit the growth of semicircle-like grains, thus resulting in Pt electrode with high active surface area. Consequently, the dye-sensitized solar cells (DSSCs) fabricated with so-prepared Pt electrodes exhibited cell efficiency of 7.39% while 0.01 vol% Me-EDA-Si was added, which is much superior to that with sputtered-Pt electrodes under the same assembly conditions. In the last part, we would like to know how additive affects the Pt nucleation and growth mechanism on the FTO surface since the additive seemingly acts as an accelerator during Pt electrodeposition by studying the FESEM images of electrodeposited-Pt electrode fabricated from a plating bath containing Me-EDA-Si. According to the current-time transients experiments and S-H theory model simulation, we found that Me-EDA-Si functions as accelerator to promote nucleation with low concentration of additive under high precursor concentration. By contrast, excess additive tends to influence the nucleation of Pt deposition towards to progressive mechanism.
34
Shu, Shi-Heng, and 許適恆. "Study the fabrication of self-assembled 3-Aminopropyltriethoxysilane (3-APTS) monolayer on silicon substrates and using it as a platform for grafting reactions." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/88666450213481547982.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
97
This research focuses on fabrication of self-assembled monolayer (SAM) of 3-Aminopropyltriethoxysilane (3APTS) on silicon substrates, and using it as a platform for the grafting reaction. A controllable method of fabricating monolayers was demonstrated which considering the surface wettability of substrates, the solubility of SAM molecule in solvent and the concentration of SAM solution during the fabrication process. Well-ordered SAM can be formed by using mixed solvents with optimized conditions. In addition, we study the synthesis of 1.4-dimethane- carboxylic acid benzene (DMCAB)-protected silver nanoparticles. UV-VIS and FTIR results suggested that the carboxylate bonding of DMCAB anchored on nanoparticle surface with a bridging bidentate type. Finally, we successfully use 3APTS SAM as a platform to graft 4-Fluorobenzoic acid (4-FBA) and silver nanoparticles on it respectively through chemical reaction.
35
Bandhyopadhyay, Sabyasachi. "Gold Electrode Functionalized with Amide SAM: Electron Transfer Properties and Fabrication of Bio-inspired Electrodes." Thesis, 2019. http://hdl.handle.net/10821/8216.
Повний текст джерелаАнотація:
Amide bonds provide primary linkage between amino acids which are basic
functional groups in biology. They support complex structures of protein backbones,
form scaffolds that transport ions and they mediate electron transfer as well.
The entire thesis work had two major objectives. First objective was to study the electron transfer properties through self assembled monolayers (SAMs) containing alkyl and amide linkages. This has been achieved by performing conventional cyclic
voltametry and chronoamperometry on alkyl and amide functionalized SAMs terminated
with a redox active group like ferrocene (Fc) and hemin. These SAM modified surfaces have been characterized using attenuated total reflection mode FTIR (ATR-FTIR)
spectroscopy, X-ray photoelectron spectroscopy (XPS) and surface enhanced Raman spectroscopy (SERS). The goal was to understand how the presence of amide linkages in the electron transfer pathway alters its rate. These rates have been compared with those obtained using straight chain alkane thiols where no amide linkage exists.
Individual residues are mutated on SAMs to understand their role in tuning the
electron transfer rate. Specifically we are interested in understanding how cysteine and tryptophan residues tune the rate of electron transfer. For this reason alkylthiol SAMs are functionalized with terminal thiol and imidazole groups, which provide coordination sites of transition metal catalysts. In particular heme based catalysts are used which bind to these terminal thiol and imidazole to create bioinspired electrodes (modified electrodes with biological structure or activity can be used for electrochemical investigations). Thiol and imidazole bound bioinspired electrodes can be used for mimicking the active sites of cytochrome P450 and myoglobin, respectively. The electron transfer rate constant as well as the reorganization energies has been determined for these catalysts bound modified surfaces using conventional “Laviron” procedure. Second objective was to study the nature of S-H bond of alkylthiols at the interfaces, forming SAMs on metal (Au/Ag) surfaces. Initially the normal Raman spectra of alkylthiols and deuterated alkylthiols were collected to determine any shift in C-S stretching mode (nCS) and C-S-H bending mode (bCSH) after deuteration. This observation was extended to the detection of SH/SD on surfaces. H/D sensitive SER spectra of a series of thiols forming SAMs on Ag and Au surfaces and NPs have been recorded. The presence of characteristic H/D shifts or the lack of any shift was then used to elucidate the protonation state of thiols in a series of SAMs.Research was carried out under the supervision of Dr. Avishek Dey of the Inorganic Chemistry division of SCS [School of Chemical Sciences]
36
THIEU, TIEN, and 武氏進韶. "Study the fabrication of self-assembled monolayers (SAMs) on transparent substrates and the deposition of aluminum doped zinc oxide (AZO) thin films on top of the SAMs modified substrates." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/57998949752338398930.
Повний текст джерелаАнотація:
博士國立臺灣科技大學
化學工程系
101
A facile, robust and effective method was used to fabricate organosilane self assembled monolayers (SAMs) on transparent substrates. Specifically, polyethylene terephthalate (PET) substrate surfaces could be chemically modified while avoiding chemical degradation. The results shown that UV – Ozone pretreatment for PET (uv-PET) substrate surfaces used favours a more densed packing of silane molecules in the self assembled processes due to generating a large surface concentration of hydrophilic moieties by UV irradiation. Various substrate surfaces having different functional groups, wettability, and the surface tension were developed by coating organosilane SAMs on PET and glass substrates. Aluminium doped zinc oxide (AZO) were deposited on transparent substrates via RF magnetron sputtering at room temperature. The sputtering parameters such as working distance and working pressure were varied from 3 to 7 cm and from 2.0 x 10-3 to 8.0 x 10-3 Torr, respectively. The effects of electron-donating/withdrawing properties of SAM functional groups on property of AZO films have been studied. The resistivity of AZO films deposited on uv-PET was decreased from 2.29 x 10-3 to 1.12 x 10-3 Ωcm by applying SAM modification at optimized conditions of 20W, 6 cm and 5.0 x 10-3 Torr. High optical transmittance of AZO films was also achieved at around 85% in visible wavelength region. The properties of SAMs on transparent substrate and the structural, electrical and optical properties of AZO films were characterized by contact angle (CA), X-ray photoelectron spectroscopy (XPS), Atomic force microscopy (AFM), X-ray Diffraction (XRD), Field-Emission Scanning electron microscope (FE-SEM), Hall measurement and Ultraviolet–visible spectroscopy (UV-Vis).