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Topuz, Burcu Berna. "Synthesis And Characterization Of Copper Phthalocyanine Deposited Mica Titania Pigment." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611519/index.pdf.
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In the present work, anatase and rutile titanium dioxide (TiO2) coated lustrous mica pigments were prepared by heterogeneous nucleation method. Anatase-rutile phase transformation of the TiO2 on mica substrate was achieved by coating very thin layers of tin (IV) oxide on mica surfaces prior to TiO2 deposition. Muscovite mica, which was used in the experiments was sieved, pre-treated with sodium bicarbonate and decantated before coating process. The surface morphology of mica titania pigments and anatase-rutile phase transformation were investigated by SEM and XRD analyse, respectively. Also, microwave-assisted synthesis of copper phthalocyanine and tetracarboxamide copper phthalocyanine pigments were carried out with phthalic anhydride and trimellitic anhydride precursors, respectively. Molecular structures of these pigments were confirmed by FT-IR and UV-visible spectroscopy analyse. Furthermore, combination pigments were obtained by the process of deposition of copper phthalocyanine pigments on mica-titania pigment substrate in dimethyl formamide solvent. FT-IR analysis and XRD analyse were performed to observe the transformations in the crystal forms of copper phthalocyanines on the substrate. The surface morphologies of copper phthalocyanines on the mica titania pigments were investigated by SEM analysis. Varying amounts of copper phthalocyanines were deposited on the mica surfaces, and nitrogen elemental analysis was performed to determine the amount of copper phthalocyanines. The resulting pigments were incorporated into alkyd based resin to prepare paint samples. L*a*b* values, gloss property, and hardness of the paint samples were determined by color measuring device, gloss meter and hardness measuring device, respectively.
The resulting combination pigments obtained in this study showed improved luster, hue, and color intensity. Furthermore, in literature it was reported that these pigments have very high bleed resistance. This can be attributed to large macromolecular structure of copper phthalocyanine on the surface of mica titania pigment that prevents bleeding of the pigment from the paint. Moreover, the paint samples obtained from combination pigments showed higher hardness with respect to the paint sample of the mica titania pigment.
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Marda, Sandeep Kumar. "PHOTOVOLTAIC CELLS BASED ON COPPER PHTHALOCYANINE AND CADMIUM SULFIDE HETEROJUNCTION." UKnowledge, 2008. http://uknowledge.uky.edu/gradschool_theses/557.
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This work focuses on the solar cell based on the heterostructure formed between Copper Phthalocyanine (CuPc) and Cadmium Sulfide (CdS). Two different fabrication techniques were used for depositing the organic and inorganic layers of CuPc and CdS layers respectively. CuPc was deposited by electrodeposition while CdS was deposited by chemical bath deposition. Hybrid CdS/CuPc thin films were obtained from CdS films grown on Glass/ITO by chemical bath deposition followed by electrodeposition of CuPc onto these films and annealing at 250˚C after the deposition of each layer. The maximum open circuit voltage (Voc) and the short circuit current density (Jsc) obtained for this heterojunction solar cell are 0.59v and 0.7mA/cm2 respectively and these are the highest values achieved in literature till date. The materials characteristics and electrical performances of the device were analyzed. The effect of increasing the thickness of CuPc and CdS on the short circuit current density and open circuit voltage were also investigated.
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Starke, Thomas. "Gas sensing applications of phthalocyanine thin films." Thesis, Nottingham Trent University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312313.
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Din, Salahud. "Copper phthalocyanine (CuPc) thin films and nanostructures : growth and device applications." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11058.
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The development and utilisation of phthalocyanine (Pc) materials for practical applications has been subject of intense research due to their desirable optical, electrical, and recently discovered magnetic properties. Typically, in crystalline organic materials the charge transport, light absorption and magnetisation are anisotropic and strongly depend on structure, morphology and molecular orientation. Hence, an understanding of growth mechanism and controlled fabrication of thin films and nanostructures is essential for tailoring properties desirable for specific applications. e.g., for OFETs, crystalline thin films or one-dimensional nanostructures. Recently, vast advancement has been made in developing functional organic films including sublimation in (ultra) high vacuum using organic molecular beam deposition (OMBD). This environment can provide the essential material purity and structural reproducibility required in future high performance optoelectronic device applications, but is unfortunately costly. In this thesis, we introduce a lesser-known technique, organic vapour phase deposition (OVPD), operating at lower cost but still maintaining high purity. The morphology, crystallinity, spectroscopic characteristics and structure of copper phthalocyanine (CuPc) thin films and nanostructures have been investigated and their dependence on deposition conditions, i.e., substrate temperature and substrate type has been studied. We compare films obtained by OMBD and OVPD and find different morphological and structural changes; the surface morphology changes from granular to larger nano-fibrous and nano-whiskers with increasing substrate temperatures. In OMBD, the structure in a small proportion of the film changes from α-CuPc to β-CuPc at a substrate temperature of 200 oC. In the case of OVPD films, extensive study of the influence of parameters such as deposition pressure, deposition time and source to substrate distance is performed and variation in film morphology, texture, structural composition and molecular orientation is observed. We find that by successive growth of films produced by OMBD and OVPD, the molecular orientation can be controlled by the first “seed” layer. With further processing and optimisation, it is hoped that this could be used to create interpenetrating networks of different organic materials and optimal molecular orientation. We also demonstrate the fabrication using OVPD of high density CuPc nanowires with typical diameters between 10 - 100 nm, high directionality, and exceptional aspect ratios. We show that these nanowires are of a new crystal phase, named eta-CuPc. Lastly, OFETs fabricated with OMBD and OVPD grown CuPc thin films and nanowires are characterised. The current on/off ratio, mobilities and threshold voltage for thin films produced by the two methods are comparable and similar to what has been reported in literature. In contrast, OFETs with CuPc nanowires show remarkable improvement in turn-on voltage, while mobilities also seem to improve dramatically, although this is difficult to quantify. The challenges in growing CuPc nanowires directly on FETs with precise control of position and directionality are reviewed. The key issues that need to be resolved for future applications of these one-dimensional nanostructures are identified and are subject of on-going research. To conclude, this work has made important contribution in the efforts to develop, improve and enhance the deposition methods for fabricating functional thin films and nanostructures of CuPc material for use in organic electronic devices.
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Chintakula, Goutam. "SCHOTTKY DIODES ON COPPER PHTHALOCYANINE NANOWIRE ARRAYS EMBEDDED IN POROUS ALUMINA TEMPLATES." UKnowledge, 2008. http://uknowledge.uky.edu/gradschool_theses/556.
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Vertically aligned nanowire arrays of copper phthalocyanine (CuPc) and CuPc-Al Schottky diodes, of controllable diameter and length were fabricated by cathodic electrodeposition of CuPc into anodized alumina (AAO) templates, followed by annealing at 300 ºC in Argon. AAO over Aluminum tape and that over ITO-glass were both used as starting templates for the device fabrication. Depending on the dimensions of the starting AAO template, diameters of CuPc nanowires ranged from 30 nm to 40 nm and the lengths ranged from 500 nm to 1 μm. The temperature dependence of the phase and the absorption spectrum of the nanowires are reported. The electrodeposited nanowires (as prepared) had the preferred crystallite orientation of the α-phase. ITO formed the ohmic contact and Schottky contacts were formed between CuPc and aluminum. Insertion of a thin layer of PEDOT:PSS between CuPc nanowires and the ITO electrode improved the contact and reduced the series resistance by an order of magnitude. Schottky diodes were characterized and analyzed at room temperature and at cryogenic temperatures.
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Willis, Michael J. "Structural and polymorphic considerations on the effects of copper phthalocyanine pigment on polypropylene." Cincinnati, Ohio University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?ucin1179176317.
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Thesis (M.S.)--University of Cincinnati, 2007.Title from electronic thesis title page (viewed July 18, 2007). Includes abstract. Keywords: polypropylene; nucleation; spherulite; copper phthalocyanine; pigment Includes bibliographical references.
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WILLIS, MICHAEL J. "STRUCTURAL AND POLYMORPHIC CONSIDERATIONS ON THE EFFECTS OF COPPER PHTHALOCYANINE PIGMENT ON POLYPROPYLENE NUCLEATION." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1179176317.
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Miller, Nicholas A. II. "Role of oxygen and water absorption on charge transport in copper phthalocyanine thin films." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10164121.
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Organic semiconductors have been studied thoroughly and are well understood, though the effects in which oxygen and humidity have on them are less well known. In this thesis we immerse copper phthalocyanine thin films deposited at two different substrate temperatures and with two different thicknesses to an environment with oxygen pressures from 10 mbar to 210 mbar and water vapor pressures from 5 mbar to 13 mbar. The conductivity of our thin films at atmospheric oxygen and water pressure ranged from as high as 6:7 × 10−4 S/m and as low as 9:6 × 10−5 S/m, about 7 orders of magnitude less than silicon and germanium. At the smallest oxygen doping, the conductivity ranged from as high as 4:9 × 10−5 S/m to as low as 1:1 × 10−5 S/m. We can conclude that the small grain samples are more easily doped by oxygen, the small grain samples have a larger sensitivity gain than the large grain samples, and the intrinsic conductivity increases as both grain size decreases and as film thickness decreases.
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Siegert, Benjamin [Verfasser], Milena [Akademischer Betreuer] Grifoni, and Jascha [Akademischer Betreuer] Repp. "STM transport through copper phthalocyanine on thin insulating films / Benjamin Siegert. Betreuer: Milena Grifoni ; Jascha Repp." Regensburg : Universitätsbibliothek Regensburg, 2015. http://d-nb.info/1080609784/34.
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Hassan, Aseel Kadhim. "Studies in electronic conduction processes in organic semiconducting thin films of copper phthalocyanine prepared by evaporation." Thesis, Keele University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306847.
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Kraus, Michael [Verfasser], and Wolfgang [Akademischer Betreuer] Brütting. "Charge carrier transport in organic field-effect devices based on copper-phthalocyanine / Michael Kraus. Betreuer: Wolfgang Brütting." Augsburg : Universität Augsburg, 2011. http://d-nb.info/1077700180/34.
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Grobosch, Mandy. "Experimentelle Bestimmung der elektronischen Eigenschaften anwendungsrelevanter Grenzflächen organischer Halbleiter mittels Photoelektronenspektroskopie." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1245078865618-45903.
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Diese Dissertation unter dem Titel Experimentelle Bestimmung der elektronischen Eigenschaften anwendungsrelevanter Grenzflächen organischer Halbleiter mittels Photoelektronenspektroskopie wurde am Leibniz Institut für Festkürper- und Werkstoffforschung (IFW) Dresden am Institut für Festkörperforschung (IFF) unter der Betreuung von Prof. Dr. B. Büchner angefertigt. Zur wissenschaftlichen Untersuchung kamen hierbei zwei Typen anwendungsrelevanter Grenzflächen. Zum einem wurde der Einfluss einer Elektrodenpräparation unter Normalbedingungen mittels ex-situ Reinigungsverfahren im Vergleich zu insitu präparierten Kontakten auf das elektronische Verhalten des organischen Halbleiters Sexithiophen an Grenzflächen zu metallischen Substraten studiert. Als Substratmaterialien kamen hierbei die Metalle Silber, Palladium, Gold und Platin zum Einsatz. In einer zweiten Studie wurden die Grenzflächen der organischen Halbleiter Sexithiophen und Kupfer(II)- Phthalocyanin in Kontakt zu dünnen Filmen des Übergangsmetalloxides La0.7Sr0.3MnO3 untersucht. Auch hier wurde eine vergleichende Untersuchung für ex-situ und in-situ gereinigte La0.7Sr0.3MnO3-Kontakte durchgeführt. Die hierzu verwendeten Filme wurden im IFW Dresden am Institut für Metallische Werkstoffe (IMW) hergestellt. Auch im Rahmen dieser Untersuchungen stand der Einfluss von Sauerstoff auf das elektronische und chemische Verhalten an den Grenzflächen im Vordergrund.
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Jayasinghe, Aroshan Park Kenneth T. "Fabrication of a single layer organic photovoltaic device based on an indium-tin-oxide/copper phthalocyanine/aluminum heterostructure." Waco, Tex. : Baylor University, 2006. http://hdl.handle.net/2104/4855.
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Ghani, Fatemeh. "Nucleation and growth of unsubstituted metal phthalocyanine films from solution on planar substrates." Phd thesis, Universität Potsdam, 2012. http://opus.kobv.de/ubp/volltexte/2013/6469/.
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Organic solar cells (OSC) are interesting as low cost alternative to conventional solar cells. Unsubstituted Metal-phthalocyanines (Pc) are excellent electron donating molecules for heterojunction OSC. Usually organic solar cells with Pcs are produced by vapor deposition, although solution based deposition (like spin casting) is cheaper and offers more possibilities to control the structure of the film. With solution based deposition several parameters (like temperature, solvent and etc.) affect the self-organized structure formation via nucleation and growth. The reason why vapor deposition is typically used is the poor solubility of the metal-phthalocyanines in most common solvents. Furthermore the process of nucleation and growth of Pc aggregates from solution is not well understood. For preparation of Pc films from solution, it is necessary to find the appropriate solvents, assess the solution deposition techniques, such as dip coating, and spin casting. It is necessary to understand the nucleation and growth process for aggregation/precipitation and to use this knowledge to produce nanostructures appropriate for OSC. This is important because the nanostructure of the films determines their performance.
In this thesis, optical absorption and the stability of 8 different unsubstituted metal Pc’s were studied quantitatively in 28 different solvents. Among the several solution based deposited thin films produced based on this study, copper phthalocyanine (CuPc) dissolved in trifluoroacetic acid (TFA) is chosen as a model system for an in-depth study. CuPc has sufficient solubility and stability in TFA and upon solution processing forms appropriate structures for OSCs. CuPc molecules aggregate into layers of nanoribbons with a thickness of ~ 1 nm and an adjustable width and length. The morphology and the number of deposited layers in the thin films are controlled by different parameters, like temperature and solution concentration. Material properties of CuPc deposited from TFA are studied in detail via x-ray diffraction, UV-Vis and FT-IR spectroscopy. Atomic force microscopy was used to study the morphology of the dried film.
The mechanism of the formation of CuPc nanoribbons from spin casted CuPc/TFA solution in ambient temperature is investigated and explained. The parameters (e.g. solution concentration profile) governing nucleation and growth are calculated based on the spin casting theory of a binary mixture of a nonvolatile solute and evaporative solvent. Based on this and intermolecular interactions between CuPc and substrate a nucleation and growth model is developed explaining the aggregation of CuPc in a supersaturated TFA solution.
Finally, a solution processed thin film of CuPc is applied as a donor layer in a functioning bilayer heterojunction OSC and the influence of the structure on OSC performance is studied.In den vergangenen Jahren wurden kosteneffiziente nasschemische Beschichtungsverfahren für die Herstellung organischer Dünnfilme für verschiedene opto-elektronische Anwendungen entdeckt und weiterentwickelt. Unter anderem wurden Phthalocyanin-Moleküle in photoaktiven Schichten für die Herstellung von Solarzellen intensiv erforscht. Aufgrund der kleinen bzw. unbekannten Löslichkeit wurden Phthalocyanin-Schichten durch Aufdampfverfahren im Vakuum hergestellt. Des Weiteren wurde die Löslichkeit durch chemische Synthese erhöht, was aber die Eigenschaften von Pc beeinträchtigte. In dieser Arbeit wurde die Löslichkeit, optische Absorption und Stabilität von 8 verschiedenen unsubstituierten Metall-Phthalocyaninen in 28 verschiedenen Lösungsmitteln quantitativ gemessen. Wegen ausreichender Löslichkeit, Stabilität und Anwendbarkeit in organischen Solarzellen wurde Kupferphthalocyanin (CuPc) in Trifluoressigsäure (TFA) für weitere Untersuchungen ausgewählt. Durch die Rotationsbeschichtung von CuPc aus TFA Lösung wurde ein dünner Film aus der verdampfenden Lösung auf dem Substrat platziert. Nach dem Verdampfen des Lösungsmittels, die Nanobändern aus CuPc bedecken das Substrat. Die Nanobänder haben eine Dicke von etwa ~ 1 nm (typische Dimension eines CuPc-Molekül) und variierender Breite und Länge, je nach Menge des Materials. Solche Nanobändern können durch Rotationsbeschichtung oder auch durch andere Nassbeschichtungsverfahren, wie Tauchbeschichtung, erzeugt werden. Ähnliche Fibrillen-Strukturen entstehen durch Nassbeschichtung von anderen Metall-Phthalocyaninen, wie Eisen- und Magnesium-Phthalocyanin, aus TFA-Lösung sowie auf anderen Substraten, wie Glas oder Indium Zinnoxid. Materialeigenschaften von aufgebrachten CuPc aus TFA Lösung und CuPc in der Lösung wurden ausführlich mit Röntgenbeugung, Spektroskopie- und Mikroskopie Methoden untersucht. Es wird gezeigt, dass die Nanobänder nicht in der Lösung, sondern durch Verdampfen des Lösungsmittels und der Übersättigung der Lösung entstehen. Die Rasterkraftmikroskopie wurde dazu verwendet, um die Morphologie des getrockneten Films bei unterschiedlicher Konzentration zu studieren. Der Mechanismus der Entstehung der Nanobändern wurde im Detail studiert. Gemäß der Keimbildung und Wachstumstheorie wurde die Entstehung der CuPc Nanobänder aus einer übersättigt Lösung diskutiert. Die Form der Nanobändern wurde unter Berücksichtigung der Wechselwirkung zwischen den Molekülen und dem Substrat diskutiert. Die nassverarbeitete CuPc-Dünnschicht wurde als Donorschicht in organischen Doppelschicht Solarzellen mit C60-Molekül, als Akzeptor eingesetzt. Die Effizienz der Energieumwandlung einer solchen Zelle wurde entsprechend den Schichtdicken der CuPc Schicht untersucht.
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Khan, Imran. "Fundamental studies of surface enhanced resonanace raman scattering and the preparation and photodegradation of photolabile copper phthalocyanine pigment precursors." Thesis, University of Strathclyde, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275124.
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Vallurupalli, Subhash C. C. "Fabrication and characterization of Schottky diode and heterojunction solar cells based on Copper Phthalocyanine (CuPc), Buckminster Fullerene (C₆₀) and titanium dioxide (TiO₂)." Lexington, Ky. : [University of Kentucky Libraries], 2005. http://lib.uky.edu/ETD/ukyelen2005t00340/Subhash.pdf.
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Thesis (M.S.)--University of Kentucky, 2005.Title from document title page (viewed on November 18, 2005). Document formatted into pages; contains xiv, 101 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 99-100).
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Vallurupalli, Subhash C. C. "Fabrication and Characterization of Schottky diode and Heterojunction Solar cells based on Copper Phthalocyanine (CuPc), Buckminster Fullerene (C60) and Titanium Dioxide (TiO2)." UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_theses/260.
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Organic solar cells are cheaper and much easier to fabricate than the conventional inorganic solar cells, but they suffer from low efficiencies due to low carrier mobilities in organic films. In this study Copper Phthalocyanine (CuPc) and Buckminster Fullerene (C60) based Schottky diodes were fabricated on ITO coated glass substrates to study their performance and a study of the effect of thickness on the cell parameters of CuPc Schottky diodes was made. Also, TiO2 based devices were studied to see the effect of TiO2 layer on the cell parameters. The J-V curves were analyzed for series resistance, diode ideality factor and reverse saturation current density. The devices were also characterized by SEM and XRD measurements.
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Sintyureva, Marina. "Engineering the phase behaviour of high performance inkjet colorants." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/engineering-the-phase-behaviour-of-high-performance-inkjet-colorants(0617f94f-7744-4576-9c05-69f659c52545).html.
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Dyes for inkjet printing are typically of the chromonic type. Chromonic mesophases have gained considerable attention as a well-defined group of lyotropic mesogens with different properties from conventional amphiphiles. While extensive research has been dedicated to the field of surfactant liquid crystals, structural and aggregation studies of chromonics have only emerged as a topic of interest within the last few years. The liquid crystalline structures in aqueous solutions of commercial Cu - phthalocyanine and black dyes have been examined using a combination of optical microscopy, UV-vis spectroscopy, nuclear magnetic resonance, wide- and small-angle X-ray diffraction and electronic paramagnetic resonance with a view to examining the phase behaviour of the chromonic mesophases formed over a broad range of concentrations and temperatures. These studies were performed in order to resolve outstanding problems concerning structural properties of these systems. Optical microscopy allowed us to identify the liquid crystalline phases and to construct the phase diagram. The observations show that both of these dyes form nematic mesophase above 15% wt / wt% dye. The small-angle diffraction data confirmed that the nematic phase for the black dye is maintained throughout the 16-25% composition range. A further increase in concentration leads to the formation of the hexagonal phase. The Cu – phthalocyanine dye also formed a nematic phase at low concentrations, with the aggregates undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye concentration. These studies showed that this ordered phase possessed hexagonal symmetry. The wide-angle X-ray results demonstrated that aggregation involved π-π stacking of the molecules into columns. An additional reflection at ca. 6.8Å was observed for the black dye, which is believed to arise from “head – to – tail” packing of the molecules within the aggregates (a similar phenomenon observed in other azo dyes, e.g. Edicol Sunset Yellow).The densities of both dyes were measured over the studied range of concentrations. This enabled us to calculate the parameters of the aggregates within the hexagonal mesophase. A comparison between the area of the molecule and the cross-section of the aggregates showed that the aggregates of both dyes were the unimolecular stacks.
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Svensson, Pamela. "DFT investigations of the donor-acceptor couple CuPc/C60." Thesis, Uppsala universitet, Materialteori, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-297935.
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The donor-acceptor couple CuPc/C60 has been the subject of recent studies in organic solar cells due to its combined abilities in light absorption (CuPc) and charge transport (C60). By better understanding the electronic and geometric nature of the system it is possible to shed light on how the molecules act under different conditions. In this study the geometric properties for three different configurations have been studied by means of Density Functional Theory (DFT). By comparing the molecular structure of pristine CuPc with the structure of CuPc in the presence of C60, a slight elongation of the bonds is observed when the fullerene is present. This is especially true for the Cu-N bonds. By further including van der Waals interactions, no change in bond lengths is observed. This, in turn, suggests that, most likely, the interaction between the two molecules is relatively weak and the C60 will not have a major influence on the electronic structure of CuPc. The N1s X-ray Photoelectron Spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) calculations confirm these conclusions, as only very small changes in peak positions are observed when comparing pristine CuPc with CuPc/C60.Tack vare sina egenskaper inom absorption och laddningsöverföring har CuPc och fullerenen C60 varit föremål för omfattande studier bland forskare inom organiska solceller. Genom att få större förståelse för den geometriska såväl som den elektroniska konfigurationen inom och mellan paret kan man förutse hur dessa kommer att bete sig i olika sammansättningar. I denna studie har de geometriska förutsättningarna studerats där olika konfigurationer beräknats genom täthetsfunktionalteori (DFT). Genom att mäta bindningslängderna mellan koppar, kol och de olika typer av kväve i CuPc i de olika systemen, kan det inses att bindningarna förlängs då C60 läggs till. Då van der Waals-interaktioner inkluderades observerades ingen större förändring i bindingslängderna i jämförelse med fallet utan van der Waals-interaktioner. Detta tyder på att växelverkan mellan de två molekylerna är relativt svag och att C60-fullerenen ej har någon större påverkan på elektronkonfigurationen i CuPc. Beräkningarna av N1s X-ray Photoelectron Spectroscopy (XPS) och Near Edge X-ray Absorption Fine Structure (NEXAFS) stödjer denna slutsats då endast små skiftningar i topparna observerades vid jämförelse mellan rent CuPc och CuPc/C60.
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Smith, Jaqueline Margaret. "Microcharacterisation of halogenated copper phthalocyanines using transmission electron microscopy." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241835.
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Granet, Julien. "Étude de l’effet Kondo au sein d’auto-assemblages de phtalocyanines par spectroscopie tunnel et photoémission." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0029/document.
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Au cours de cette thèse, nous nous sommes intéressés à l'effet Kondo moléculaire au sein de réseaux supramoléculaires bidimensionnels en contact avec des surfaces métalliques monocristallines. Les techniques mises en oeuvre sont la diffraction d'électrons lents (LEED) et la microscopie à effet tunnel (STM) pour l'étude de la croissance ainsi que la spectroscopie à effet tunnel (STS) et la photoémission pour l'étude des propriétés électroniques. Les molécules employées dans le cadre de ce travail sont composées de macrocycles de phtalocyanine et tétraphénylporphyrine. Elles ont été choisies sur la base de l'orbitale contenant le spin moléculaire. Dans un premier cas, une phtalocyanine non métallée 2HPc a été déposée sur une surface monocristalline d'Ag(111). Un transfert de charge du métal vers la molécule conduit à l'apparition d'un effet Kondo à base température observé par STS sur des molécules individuelles ainsi que sur des auto-assemblages. Dans le deuxième cas, nous avons choisi un composé hôte à double plateaux contenant un ion cérium de type 4f. Nous avons mis en évidence l'influence du substrat sur l'effet Kondo. En effet, tandis que nous observons par STS, l'apparition d'une résonance Kondo lorsque la molécule est auto-assemblée sur Ag(111), aucun effet n'est observé sur Cu(111). Les résultats sont discutés en terme d'interactions molécule-molécule et molécule-substratIn this work, we investigated molecular Kondo effect in two-dimensional supramolecular lattices adsorbed on metallic single crystalline surfaces by means of low-energy electron diffraction (LEED), scanning tunneling microscopy/spectroscopy (STM/STS) and photoemission (PES). The molecular compounds used in this PhD thesis have been chosen in regards to their spin orbital. The first molecule under investigation is a metal free phthalocyanine adsorbed on Ag(111). A Kondo effect has been evidenced by STS for single molecules as well as for self-assembly up to one monolayer coverage at low temperature. In that case, the spin originates from charge transfer from the Ag surface to the molecule. The second molecular compound is a double-decker molecule hosting a cerium 4f-ion. In that case, a Kondo resonance is evidenced by STS when it is self-assembled on Ag(111) whereas it is absent on Cu(111). These results are discussed in terms of intermolecular and molecule-metal interactions
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Cox, Jennifer Jane. "Structure of organic molecular thin films vapour deposited on III-V semiconductor surfaces." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327025.
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Chen, Jun Yan, and 陳俊諺. "Synthesis and characterization of polymeric copper phthalocyanine." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/69227308222695134424.
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CHUANG, TZ-YING, and 莊子瑩. "Morphology Study of Mixed Copper Phthalocyanine (CuPC)-Fullerene (C60) Molecular Heterojunction." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/22854276990622623709.
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碩士輔仁大學
化學系
97
In this thesis, we investigated the heterojunction morphology in the small weight molecular solar cells. Copper Phthalocyanine (CuPC), electron donor, and Fullerene (C60), electron acceptor, blend films were fabricated by vacuum co-evaporation and annealing at different temperatures. These films have been characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM). The SEM and AFM images have shown that the aggregation of CuPC and C60 become more serious, and crystals appeared with increased temperature. The results of photoluminance (PL) and lifetime measurements suggested that the stacked molecule would decrease the intensity in PL and lifetime. Different deposit rate would cause different molecule cluster grain size evaporated on substrate. Through SEM images and device measurements, it is found that the power conversion efficiency would become better when the deposit rate is larger. The reason is the distance between molecular clusters on substrate getting closer and therefore increasing the mobility as raising the deposit rate.
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Lin, Chien-Hung, and 林建宏. "A Photoemission Study of Electronic Structures at the calcium / copper phthalocyanine Interface." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/34847165434065690148.
Full textAbstract:
碩士國立清華大學
材料科學工程學系
95
In this project, we have utilized synchrotron radiation photoemission to investigate how the organic semiconductor CuPc interacts with Ca at different thicknesses. According to our observations, the interaction at the Ca/CuPc interface can be divided into four stages. In stage I, where the evaporation time is less than 15 s, the Ca atoms transfer some charge to CuPc, making both the HOMO and the cutoff shift to high binding energies. In stage II, where the evaporation time is less then 100 s, a new peak appears inside the CuPc gap, while the HOMO and the cutoff remain unshifted. The new peak increases in intensity with increasing Ca thickness. As to the N 1s and C 1s core-level spectra, they become broadened. Furthermore, a new Cu 3p core appears at low binding energy, shifted away from the pristine 3p core by 1.6 eV. In stage III, where the evaporation time is less than 500 s, the strength of the new valence peak does not increase, and the whole valence band spectra change insignificantly. However, the new Cu 3p core increases in intensity at the expense of the original Cu 3p core. In the final stage, where the evaporation time is greater 500 s, the metallic Ca appears.
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Yu, Ting-Shu, and 游定書. "Mixed Organic Thin Films of Copper Phthalocyanine and Rubrene: Characterization and Transistor Application." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/59421581632014195257.
Full textAbstract:
碩士國立清華大學
化學系
100
Mixed organic semiconducting thin films were prepared by vacuum-depositing copper phthalocyanine (CuPc) and rubrene of different mixing ratio onto oxide-terminated Si(100) wafers that were pre-modified with self-assembled monolayer (SAM) of either octadecyltrichlorosilane (OTS) or 4-phenylbutyltrichlorosilane (4-PBTS). The thin films were characterized by atomic force microscopy (AFM) and various synchrotron-based techniques such as x-ray photoemission spectroscopy (XPS), x-ray diffraction (XRD), and near-edge x-ray absorption fine structure (NEXAFS) spectroscopy to obtain the information about the thin films in various aspects such as electronic structure, morphology, crystallinity, averaged molecular orientation, etc. The out-of-plane XRD data show that all the mixed films are composed of CuPc in predominately crystalline from and rubrene in exclusively amorphous form. More informative structural change can be obtained by examining grazing incidence x-ray diffraction (GIXD) images. For pure CuPc film, the a-b plane of CuPc crystallite is found to be parallel to the substrate surface. For the films of increasing rubrene percentage, the CuPC crystallite becomes tilted away from the substrate surface, forming elongated diffraction spots. For the mixed film of the highest rubrene percentage (90%), CuPc crystallites decrease in size, lose surface registry, and become powder-like samples, producing characteristic powder-diffraction rings. In consistence with the structural change documented by x-ray diffraction data, the average tilt angle of CuPc molecules, measured from the surface, also decreases dramatically by up to 10°, as recorded by NEXAFS data. Moreover, there seems to be very little chemical interaction between CuPc and rubrene molecules so as to effect observable changes in XPS N 1s spectra and N K-edge NEXAFS spectra (incidence angle of 55°) for CuPc of different mixed films. Organic field effect transistors based on the aforementioned mixed semiconducting films were fabricated. For mixed-film OFET, a modest mobility of at least 2 × 10–2 cm2/Vs can all be obtained, with the best value of 5.9×10–2 cm2/Vs obtained for the mixed film of 75% CuPc+25 % rubrene grown on 4-PBTS substrate. Comparing the AFM images with mobility data, we found that a larger width in the characteristic CuPc features in AFM image seems to give better electrical performance, suggesting a beneficial effect exerted by the larger CuPC grains.
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Kung, Li-Jen, and 龔立仁. "High-performance organic thin-film transistors with copper phthalocyanine-modified source/drain contacts." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/32671442937312071825.
Full textAbstract:
碩士國立交通大學
顯示科技研究所
94
The insulator surface treatment transforms the hydrophilic SiO2 surface to hydrophobic one that is more suitable for organic materials deposition. Organic thin-film transistors (OTFTs) modified by poly(��-methylstyrene) (P�埒S) exhibit a high mobility (0.5 cm2/Vs ) with a high on/off ratio ( > 106 ). Copper phthalocyanine (CuPC) has been used as the contact buffer layer to improve the device performance of organic thin-film transistors (OTFTs). By incorporating with 10 nm CuPC, the contact resistance was decreased to 70%, deduced from line-transfer method. The mobility was also improved by 86%. The higher hole current observed in the hole-only diode incorporating with CuPC further confirm the improvement of hole-injection efficiency. Finally, it is inferred that the lower injection barrier is resulted from the induced gap states at the Au/CuPC interfaces.
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Tang, Fu-Syong, and 湯富雄. "Thermal annealing effect of copper phthalocyanine on the performance of organic light-emitting diode." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/83968178138068413281.
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Chen, Chun-Ming, and 陳俊銘. "A Study on NO Gas Sensing Properties with Lead, Copper, and Nickel Phthalocyanine Thin Films." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/11900162788633234410.
Full textAbstract:
碩士國立臺灣大學
化學工程學系
86
This study is on the gas-sensing properties of nitric monoxide（NO） with organic semiconductors, such as lead, copper, and nickel phthalocyanines. The metal phthalocyanine thin films were vacuum deposited on sapphire substrates with interdigitated gold electrode and assembled into a sensing head. The sensing head is placed into the gas-sensing chamber for the detection of NO gas. When expose to the NO gas, the films adsorbed gas molecules and cause the change in conductance. It was found that the deposition conditions do affect the film''s surface morphology and crystal structure, and hence causing the difference in sensing properties. In this work, we kept the deposition conditions fixed while varying various organic solvents in treating phthalocyanine thin films. It''s concluded that solvent treatments also play an important role in film''s morphology and crystal form. Based on our experiment results, among thermally deposited metal phthalocyanines thin films studied, only the lead phthalocyanine possess good sensing properties when exposed to low concentration (<100ppm) of NO gas. The other two types of non-treated phthalocyanines (CuPc, NiPc) could not reach an equilibrium state in a brief time when exposed to ambient NO gas. Among various solvent vapors treated phthalocyanine thin films, the ethanol vapor treated thin films possess better sensing properties to nitric monoxide, showing shorter response time and faster desorption rate. Finally, the non-linear diffusion mechanism is used to fit experimental data and to obtain the adsorption constant, diffusion coefficient, trap concentrations and γ values. It is concluded that films with smaller power index (γ) possess larger adsorption constant (k). The diffusion coefficient （D=N0 x0^2/C0t）is proportional to the trap concentrations (N0) and decreases with the increase of the diffusion time (τ). For non- treated lead phthalocyanine film of 1000A thickness, diffusion constant D=5.03×10^-12 m2/s and adsorption constant k=2.06×10^18（1/ m3 ）^0.62 are obtained. For ethanol vapor treated lead phthalocyanine, diffusion constant D=4.65×10^-13 m2/s and adsorption constant k=1.47×10^11（1/ m3）0.35 are obtained, and possess larger effective diffusion constant and shorter response time.
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Hsiao, Jung-Hua, and 蕭榮華. "The study of nitrogen dioxide gas sensing properties of vacuum deposition copper phthalocyanine thin film." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/b7mz7w.
Full textAbstract:
碩士國立成功大學
化學工程學系碩博士班
92
Copper phthalocyanine was vacuum deposition onto gold electrode. The effects of substrate temperature and post-deposition annealing on the film morphology and crystalline structure were studied. The film characteristics were related to their sensing propertied to NO2. The results show that the CuPc films which deposition at low substrate temperature (Td = 25℃) have fine-grain morphology and the stacking axis (b axis) of CuPc molecules is normal to the substrate. When Td is elevated to 100-200℃, fiber-like morphology was observed, with orientation mainly parallel to the substrate. XRD results shows that CuPc thin film have a diffraction peak at 2�� = 6.86∘and the peak intensity increases with increasing substrate temperature. The gas sensing properties shows that the fiber-like structure prepared at Td = 100℃ have the largest current change (sensitivity) value and highest adsorption-desorption equilibrium constant due to its higher highest electrical conductivity and large surface area. After annealing time 2 hr of heat annealing at 200℃, the XRD peak intensity increases but a longer gives no effect to increase the peak intensity further. CuPc films have smoother morphology after heat annealing which lead to a smaller sensitivity.
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Lin, Yi-Ting, and 林怡婷. "Fabrication of copper phthalocyanine based organic thin-film transistors with silk fibroin as the gate dielectric." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/96643434023593944382.
Full textAbstract:
碩士國立清華大學
材料科學工程學系
101
In this thesis, we have used silk fibroin as the gate dielectric layer and CuPc as the p-type semiconductor material to fabricate organic thin-film transistors (OTFTs). Experimental parameters include the substrate temperature during thermal deposition, CuPc thickness and the passivation layer. When the depositing substrate temperature is 90℃ and the thickness of CuPc is 45nm, a field-effect mobility value of 0.96 cm2V-1s-1, an on/off ratio of ca. 1.1x103 and a threshold voltage of -2.08V are achieved. AFM and GIXRD were used to characterize the CuPc thin film. The morphology of the CuPc thin film strongly depends on temperature, specifically in the grain size and shape. At 30℃, the CuPc grains are needle-like. When the temperature increases to 90℃, the CuPc grains become rod-like. When CuPc is deposted on silk fibroin, the degree of crystallization of CuPc thin film is better than that on the untreated SiO2. TTC was used as the passivation layer to reduce the hysteresis loop and to increase the stability of the device. Ambipolar OTFTs with a bilayer of CuPc and F16CuPc was also fabricated. A bilayer of 45nm CuPc/ 30nm F16CuPc exhibits the best performance of ambipolar characteristics. The field-effect mobilities of electrons and holes are 0.14 and 0.03 cm2V-1s-1 respectively. With the assistance of the TTC passivation layer, 45 nm CuPc/ 17 nm F16CuPc ambipolar exhibits better ambipolar characteristics. The field-effect mobilities of electrons and holes are 0.035 and 0.47 cm2V-1s-1 respectively.
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CHOU, TING-WEI, and 周廷衛. "The Study of Removal Mechanisms in Copper Phthalocyanine by Photocatalyst TiO2 and Activated Carbon in Water." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/75865875352848752171.
Full textAbstract:
碩士弘光科技大學
環境工程研究所
104
In recent years, the development of electromechanical materials, such as: field effect transistor (FET), semiconductor and optoelectronics were replaced with the organic materials. The organic semiconductor material had high absorption rate, low cost, good flexibility and wide coverage. It was better than inorganic semiconductor material. The organic dye was widely used in the manufacturing process. Because of copper phthalocyanine had a chemical stability, adhesion resistance, light resistance, low production costs and sustain in high temperature, etc. Therefore, the copper phthalocyanine was applied widely. Due to its high stability, the process leading to the factory discharged waste water was not generally easy to use chemical or physical treatment. The effluent water contained large amounts of suspended solids, high oxygen demand, pH, colour and low biodegradation. In this study used titanium dioxide (TiO2) and activated carbon (AC) to degrade copper phthalocyanine, and experimental factors of single activated carbon, single titanium dioxide and both. The result indicated that the CuPc treated with long-term UV light to caused higher abs values, since the photocatalytic destroyed copper phthalocyanine of huge and complex structure. The macro-molecular structure of copper phthalocyanine cleaved into small copper phthalocyanine isomers, and added the photocatalyst of TiO2 to form light copper phthalocyanine isomers fastly. In addition, added the 60 mg/L activated carbon in the temporized test, the removal rate of copper phthalocyanine could be up to 100%, and the condition of pH3 and pH7 lasted 300 min and 210 min, respectively. Adding activated carbon increase 55.7 % COD, and 57.7% NH3-N removal efficiency in neutral environment. Finally, the photocatalytic reaction of CuPc improved the adsorption capacity of activated carbon.
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Chen, Wei-Hung, and 陳威宏. "1.Fabrication of copper phthalocyanine rods on gold nanoparticle films and its application in organic solar cells2.Mechanical properties of biomolecules studies using atomic force microscopy." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/9e9rs5.
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博士國立中興大學
化學系所
98
Two topics are included in this thesis: (1) Fabrication of copper phthalocyanine (CuPc) rods on gold nanoparticle (AuNP) films and its application in organic solar cells. (2) Mechanical properties of biomolecules studies using atomic force microscopy. To improve the performance of CuPc-based photovoltaic devices, we tried to synthesize rod-like CuPc, which was thought to be beneficial to increase the interfacial area, and incorporate AuNP films, which have special optical and electric properties. And we fabricated this cell using electrochemical deposition techniques coupled with micelle disruption methods to provide a cheaper and more rapid way to product organic photovoltaic devices. The preliminary results of photocurrent measurements showed that AuNP films indeed increase the photocurrent of CuPc comparing with the CuPc photovoltaic cell without AuNP films. Single molecule manipulation technique, which can control the movement with angstrom-level accuracy and apply force with piconewton precision, was used to study the mechanical properties of titin proteins, double-stranded deoxyribonucleic acid (dsDNA) and single-stranded deoxyribonucleic acid (ssDNA). At the case study of titin proteins, the force spectrum of a commercial engineered recombinant protein consisting of eight repeated muscle protein immunoglobulin-like domain I27 was obtained. And using Jarzynski''s equation, we try to reconstruct the free energy surface of stretching and unfolding muscle proteins. The thermodynamic properties extracted from the free energy were consistent with ensemble experiments data. At the case study of dsDNA, biological information hidden under its force spectrum, which showed B-S transition and double helical structure melting patterns, was discussed. At the case study of ssDNA, the force spectrum of synthetic ssDNA polydeoxyadenylate (poly(dA)) was obtained. The pattern of base unstacking induced by the mechanical force can be directrly observed in the force spectrum. And we also found that the unstacking process conducted multiple pathways, and "hopping" between these pathways could be observed during constant force measurements.
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Krzywiecki, Maciej. "Studies of CuPc ultra-thin layers deposited on Si(111) native substrates." Praca doktorska, 2010. http://ruj.uj.edu.pl/xmlui/handle/item/41644.
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"Charge carrier transport in copper phthalocyannie organic semiconductor." 2004. http://library.cuhk.edu.hk/record=b5891946.
Full textAbstract:
Tsang Sai-wing.Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references.
Abstracts in English and Chinese.
ABSTRACT (ENGLISH) --- p.I
ABSTRACT (CHINESE) --- p.III
ACKNOWLEDGEMENTS --- p.IV
TABLE OF CONTENTS --- p.V
Chapter 1. --- INTRODUCTION --- p.1
Chapter 2. --- ELECTRONIC STRUCTURE OF ORGANIC SEMICONDUCTORS --- p.6
Chapter 2.1 --- Introduction of energy-band diagram in organic semiconductors --- p.7
Chapter 2.1.1 --- Organic semiconductors --- p.7
Chapter 2.1.2 --- Density of state (DOS) and traps distribution --- p.8
Chapter 2.1.3 --- Metal/organic interface --- p.10
Chapter 2.1.4 --- Surface morphology and crystallinity of organic semiconductors --- p.12
Chapter 2.2 --- Experimental --- p.14
Chapter 2.2.1 --- Experimental scheme --- p.14
Chapter 2.2.2 --- Sample preparation --- p.14
Chapter 2.3 --- Data analysis and discussions --- p.15
Chapter 2.3.1 --- Surface morphology on substrate temperature effect --- p.15
Chapter 2.3.2 --- Characteristics of trap in CuPc thin film --- p.19
Chapter 2.4 --- Conclusions --- p.20
Reference --- p.22
Chapter 3. --- CHARGE TRANSPORT IN CuPc ORGANIC SEMICONDUCTORS --- p.25
Chapter 3.1 --- Introduction --- p.26
Chapter 3.1.1 --- Carrier injection at metal-organic interface --- p.26
Chapter 3.1.2 --- Carrier transport in organic semiconductors --- p.28
Chapter 3.1.2.1 --- Polaron models --- p.29
Chapter 3.1.2.2 --- Scher-Montroll model - Anomalous dispersive transport --- p.29
Chapter 3.1.2.3 --- Gaussian disorder model --- p.32
Chapter 3.2 --- Experimental
Chapter 3.2.1 --- Experimental scheme --- p.35
Chapter 3.2.2 --- Sample preparation --- p.35
Chapter 3.2.3 --- Admittance spectroscopy --- p.35
Chapter 3.2.4 --- Dark injection space-charge-limited transient current measurement --- p.39
Chapter 3.3 --- Results and discussions --- p.41
Chapter 3.3.1 --- Simulation results of admittance spectroscopy --- p.41
Chapter 3.3.2 --- Experimental results of Au/CuPc/Au devices by admittance spectroscopy --- p.49
Chapter 3.3.2.1 --- Field dependent hole mobility of CuPc --- p.49
Chapter 3.3.2.2 --- Thickness dependent dispersive transport --- p.53
Chapter 3.3.3 --- Experimental results of Au/CuPc/Au devices by dark-injection space-charge-limited transient current measurement --- p.55
Chapter 3.4 --- Conclusions --- p.58
Reference --- p.59
Chapter 4. --- NEGATIVE CAPACITANCE IN AU/CUPC/AU DEVICES --- p.61
Chapter 4.1 --- Introduction of negative capacitance in different material systems --- p.62
Chapter 4.2 --- Experimental --- p.63
Chapter 4.2.1 --- Experimental scheme --- p.63
Chapter 4.2.2 --- Sample preparation --- p.63
Chapter 4.3 --- Data analysis and discussions --- p.64
Chapter 4.4 --- Conclusions --- p.70
Reference --- p.71
Chapter 5. --- HOLE TRANSPORT IN COPPER PHTHALOCYANNINE UNDER VARIOUS AMBIENT CONDITIONS --- p.72
Chapter 5.1 --- Introduction --- p.73
Chapter 5.1.1 --- Current development of organic sensors --- p.73
Chapter 5.1.2 --- Underlying mechanisms in sensing applications --- p.74
Chapter 5.2 --- Experimental --- p.76
Chapter 5.2.1 --- Experimental scheme --- p.76
Chapter 5.2.2 --- Sample preparation --- p.77
Chapter 5.3 --- Data analysis and discussions --- p.78
Chapter 5.4 --- Conclusions --- p.83
Reference --- p.84
Chapter 6. --- SUMMARY AND FUTURE WORK --- p.85
Summary --- p.85
Future work --- p.87
APPENDIX A: derivation of complex admittance --- p.89
APPENDIX B: derivation of transient relaxation current --- p.92
APPENDIX C: simulation for admittance spectroscopy --- p.95
APPENDIX D: publications which contributed to this thesis --- p.99
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Raghuraman, Mathangi. "Threshold Voltage Shift Compensating Circuits in Non-Crystalline Semiconductors for Large Area Sensor Actuator Interface." Thesis, 2014. http://hdl.handle.net/2005/3176.
Full textAbstract:
Thin Film Transistors (TFTs) are widely used in large area electronics because they offer the advantage of low cost fabrication and wide substrate choice. TFTs have been conventionally used for switching applications in large area display arrays. But when it comes to designing a sensor actuator system on a flexible substrate comprising entirely of organic and inorganic TFTs, there are two main challenges – i) Fabrication of complementary TFT devices is difficult ii) TFTs have a drift in their threshold voltage (VT) on application of gate bias. Also currently there are no circuit simulators in the market which account for the effect of VT drift with time in TFT circuits.
The first part of this thesis focuses on integrating the VT shift model in the commercially available AIM-Spice circuit simulator. This provides a new and powerful tool that would predict the effect of VT shift on nodal voltages and currents in circuits and also on parameters like small signal gain, bandwidth, hysteresis etc. Since the existing amorphous silicon TFT models (level 11 and level 15) of AIM-Spice are copyright protected, the open source BSIM4V4 model for the purpose of demonstration is used. The simulator is discussed in detail and an algorithm for integration is provided which is then supported by the data from the simulation plots and experimental results for popular TFT configurations.
The second part of the thesis illustrates the idea of using negative feedback achieved via contact resistance modulation to minimize the effect of VT shift in the drain current of the TFT. Analytical expressions are derived for the exact value of resistance needed to compensate for the VT shift entirely. Circuit to realize this resistance using TFTs is also provided. All these are experimentally verified using fabricated organic P-type Copper Phthalocyanine (CuPc) and inorganic N-type Tin doped Zinc Oxide (ZTO) TFTs.
The third part of the thesis focuses on building a robust amplifier using these TFTs which has time invariant DC voltage level and small signal gain at the output. A differential amplifier using ZTO TFTs has been built and is shown to fit all these criteria. Ideas on vertical routing in an actual sensor actuator interface using this amplifier have also been discussed such that the whole system may be “tearable” in any contour. Such a sensor actuator interface can have varied applications including wrap around thermometers and X-ray machines.