Over the past few decades, metal phthalocyanines (MPcs) have been thoroughly investigated as active materials in organic field-effect transistors (OFETs) towards the commercialization of flexible integrated circuits and displays. One of several advantages to MPcs as building blocks for OFETs is the high degree of functionality, from which the choice of metal ion, substituents along with the phthalocyanine framework and axially bound ligands can synergistically tune the physical and self-assembly properties of the material. Recent interest has been directed to the introduction of main-group elements as the central ion of MPcs as an avenue to install both hole and electron transport properties and improve device performance. To prepare materials that are suitable to be employed as the semiconducting active layer in organic field-effect transistors, a family of novel silicon phthalocyanine derivatives was prepared. The synthesis and optoelectronic properties of those new axially disubstituted silicon phthalocyanines are detailed in this work. Axial ligand variation mainly includes alkylsiloxy derivatives. The emphasis of the current thesis, however, is on tailoring the Pc backbone, which includes replacing the four benzene units with pyrazine moieties, extending the degree of conjugation with naphthalene, and introducing substituents on their peripheral positions. Several metal-containing tetra-2,3-pyrazinoporphyrazines are also described, but their applications are limited due to the difficulty of purification. Specifically, Chapter 1 serves as a comprehensive review of main-group phthalocyanines and their use as active materials in organic field-effect transistors. In Chapter 2, silicon tetra-2,3-pyrazinoporphyrazine complexes are explored. The isosteric substitution of CH groups in Pc macrocycle for nitrogen atoms leads to an obvious hypsochromic shift in their main absorption band, and their relatively low energy levels make them promising air-stable n-type organic semiconducting materials for OFETs. The synthesis and characterization of silicon tetra(tert-butyl)-2,3-naphthalocyanine complexes are described in Chapter 3. The extension of π-conjugation leads to obvious bathochromic shifts in the main absorption band. In addition, the introduction of tert-butyl groups on the periphery of the molecule reduces the tendency of the naphthalocyanine molecules to aggregate, thereby increase their solubility. Chapter 4 covers the synthesis and characterization of zinc tetra-2,3-pyrazinoporphyrazine and cobalt tetra-2,3-pyrazinoporphyrazine, whereas more future works are expected. The fifth chapter provides a conclusion to this work, and possible future directions of the research conducted herein.

Cette thèse démontre le potentiel d'utilisation du graphène pour la fabrication de transistors à effet de champ à couche mince. Celui-ci est préparé par exfoliation en phase liquide et co-déposé avec un polymère semiconducteur du type n. Cette stratégie montre que le graphène améliore le comportement ambipolaire du polymère et plus particulièrement le transport des trous ce qui renforce l'application des matériaux composites au graphène dans les circuits logiques.Par la même approche de mélange, de nouveaux nanorubans de graphène dispersés en solution, ont été utilisés pour améliorer la performance des dispositifs basés sur un polymère amorphe de type p. Ces nanorubans forment une voie de percolation pour les charges améliorant ainsi la performance des dispositifs dans l'obscurité ainsi que sous illumination. Finalement, les dispositifs photosensibles multifonctionnels ont été examinés par l'introduction de molécules photochromiques avec différents substituants au sein des films semi-conducteurs à base de polymère ou de molécules de petite taille qui ont été trouvés influer la photocommutation. / This thesis demonstrates that graphene produced by liquid-phase exfoliation can be co-deposited with a polymerie semiconductor for the fabrication of thin film field-effect transistors. The introduction of graphene to the n-type polymeric matrix enhances not only the electrical characteristics of the devices, but also the ambipolar behavior and the hole transport in particular. This provides a prospective pathway for the application of graphene composites for logic circuits.The same approach of blending was adopted to enhance the electrical characteristics of an amorphous p-type polymer semiconductor by addition of an unprecedented solution processable ultra-narrow graphene nanoribbon. GNRs form percolation pathway for the charges resulting in enhanced deviee performance in daras weil as under illumination therefore paving the way for applications in (opto)electronics.Finally, multifunctional photoresponsive devices were examined by introducing photochromic molecules exposing different substituents into small molecule or polymeric semiconductor films that were found to affect the photoswitching behavior.

A high aspect ratio epoxy mask has been built with Taiyo PSR4000BN on chemical sensing array chip. Thickness up to 200 and #61549;m and aspect ratio up to 16:1 have been achieved with this material. It is demonstrated that this material satisfies the mechanical and chemical requirements. A three-electrode system has been designed and built for electrochemistry in micro-cell on chip. Tests with poly(phenylenesulfide-phenyleneamine) (PPSA) demonstrates that it is possible to precisely tune the properties (Work function and resistance) of conducting polymer that has been cast on chip surface. A new test platform GT03 has been fabricated and used to characterize the chemical effects on organic electronics. It is demonstrated that the chemical species in ambient environment can affect organic electronics properties on bulk, interface and electric contact. The contact resistance in organic field-effect transistors (OFETs) has been characterized with modified interdigitated structure (IDS). It is demonstrated that drain and source contact resistances can be calculated separately with modified four-point-probe measurements, and contact resistance and material bulk resistance are actually modulated by the gate electric field. Furthermore, the influence from oxygen doping in poly(3-hexylthiophene) (P3HT) based OFETs has been investigated. A new model of oxygen doping has been suggested and it is demonstrated that oxygen doping can affect all the resistance components in P3HT OFETs.

This work reports the various aspects of the application of atomic force microscopy (AFM), for the characterization of organic semiconductors and DNA-based arrays, for organic electronics and biological applications. On these soft surfaces, the amplitude modulation AFM mode was chosen. This choice is argued by a study of dissipative processes, performed on a particular sample, a DNA chip. We showed the influence of experimental parameters on the topographic and phase image quality. By calculating the dissipative energy, it was shown that the dissipation on the DNA chip was mainly induced by a viscoelastic tip-sample interaction.The AFM study of the "thickness-driven" pentacene growth was made to link the morphology to the nature of the substrate and to the electrical performance of created pentacene-based Organic Field Effect Transistor (OFET). Deposited on two polymer substrates, parylene and benzocyclobutene (BCB), pentacene has been characterized for nanoscale film thicknesses between 6 and 60nm. It has been shown that the larger grains were created for a deposited thickness of 30nm. Spectroscopic AFM mode was used as an alternative to the method of contact angles, to measure local surface energy. Decrease of surface energy is characteristic of a more ordered surface and was measured for a thickness of 30 nm of pentacene deposited on both substrates. Models of statistical analysis of spectral images, based on the Power Spectrum Distribution (PSD) have been used to explain the morphology of pentacene films. In addition, these models have provided a comprehensive description not only of the accessible surface of the sample, but also of its internal structural properties. Highlighted in the models, the critical thickness of 30 nm corresponds to a transition from the orthorhombic phase to the triclinic phase for pentacene molecules deposited on parylene. Similarly, a polymorphic transition occurs on the BCB. On OFETs, based on pentacene on BCB, the largest mobility of 3.1x10-2 cm²/Vs corresponds to the pentacene layer of 30nm, that shows a better ordering of the orthorhombic molecular packing in comparison with the triclinic packing.The molecular arrangement of X and Y structures based on DNA was observed, by AFM, in air and in two buffer solutions of Tris and HEPES on a mica substrate. It was shown that the treatment of the mica by Ni2 + ions increases the strength of the DNA/substrate interaction and reduces the diffusivity of the molecules. In air, wired macromolecules containing one double-stranded structure are observed on untreated mica and macromolecules with a 2D geometry on pretreated mica. Onto a non-treated, the greater thermal motion of weakly bounded to mica DNA molecules leads to the rupture of intermolecular bonding and the forming structures are more simple and not branched. The organization is different in solutions of Tris and HEPES. In the Tris solution, containing Mg2+ cations, the arrangement leads to a well-organized 2D architecture. In the HEPES solution, containing Ni2+ cations, the ionic strength is 10 times lower, this leads to a breaking of the bonds previously formed between DNA and mica. However, DNA molecules are near each other due to a partial substitution of already adsorbed Mg2 + cations by Ni 2 + cations of higher affinity with the mica. These results show that the two liquids promote a 2D assembly. In air, the networks are not stable and the few observed ones remain in a dendritic structure on the surface of pretreated mica and as a linear macromolecule on the untreated mica.

This thesis demonstrates that graphene produced by liquid-phase exfoliation can be co-deposited with a polymerie semiconductor for the fabrication of thin film field-effect transistors. The introduction of graphene to the n-type polymeric matrix enhances not only the electrical characteristics of the devices, but also the ambipolar behavior and the hole transport in particular. This provides a prospective pathway for the application of graphene composites for logic circuits.The same approach of blending was adopted to enhance the electrical characteristics of an amorphous p-type polymer semiconductor by addition of an unprecedented solution processable ultra-narrow graphene nanoribbon. GNRs form percolation pathway for the charges resulting in enhanced deviee performance in daras weil as under illumination therefore paving the way for applications in (opto)electronics.Finally, multifunctional photoresponsive devices were examined by introducing photochromic molecules exposing different substituents into small molecule or polymeric semiconductor films that were found to affect the photoswitching behavior.

Ce travail de thèse porte sur les divers aspects de l'application de la microscopie à force atomique (AFM), pour la caractérisation de semi-conducteurs organiques et de réseaux d’ADN, pour des applications en électronique organique et en biologie. Sur ces surfaces molles, le mode de fonctionnement Amplitude modulation de l’AFM a été choisi. Ce choix est argumenté par une étude des processus dissipatifs, réalisée sur un échantillon particulier, une puce à ADN. Nous avons montré l’influence des paramètres expérimentaux d’amplitude sur la qualité des images topographique et de phase. A partir du calcul de l’énergie dissipative, il a été montré que la dissipation sur la puce ADN était principalement induite par une interaction pointe-échantillon de type viscoélastique. L’étude par AFM de la croissance “thickness-driven“ du pentacène a été réalisée afin de relier sa morphologie à la nature du substrat et aux performances électriques pour la réalisation de transistors organiques à effet de champ, OFET (Organic Field EffectTransistor). Déposé sur deux substrats de polymères, le parylène et le benzocyclobutène (BCB), le pentacène a été caractérisé à l’échelle nanométrique pour des épaisseurs de film entre 6 et 60nm. Il a été démontré que les grains créés par le dépôt étaient les plus étendus pour une épaisseur déposée de 30nm. La spectroscopie AFM en mode contact a été utilisée, comme une alternative à la méthode des angles de contact, pour mesurer localement l'énergie de surface. Une énergie de surface minimale caractéristique d’une surface mieux ordonnée a été mesurée pour l’épaisseur de pentacène déposée de 30nm pour les deux substrats. Des méthodes spectrales d'analyse statistique d’images, à base de PSD (Power Spectrum Density), ont été utilisées pour expliquer la morphologie des films de pentacène. En outre, ces modèles ont fourni une description exhaustive non seulement de la surface accessible de l’échantillon, mais aussi de ses propriétés structurales intérieures. Mise en évidence dans les modèles, cette épaisseur critique de 30nm correspond à une transition de la phase orthorhombique à la phase triclinique pour les molécules de pentacène déposées surparylène. De même, une transition polymorphique se produit sur le BCB. Sur des OFET créés à base de pentacène sur BCB, la mobilité la plus importante de 3.1x10-2cm²/Vs correspond à la couche de pentacène de 30nm, ce qui montre l'avantage de l'moléculaire orthorhombique en comparaison du triclinique. L’assemblage moléculaire de structures en X et en Y à base d’ADN a été observé par AFM à l’air et dans deux solutions buffer de Tris et HEPES sur un substrat de mica. Il a été montré que le traitement du mica par des ions Ni2+ augmente la force d’interaction ADN/substrat et réduit la diffusivité des molécules. A l'air, des macromolécules filaires contenant une seule structure double brin sont observées sur le mica non traité et des macromolécules avec une géométrie 2D ramifiée, sur le mica prétraité. Sur une surface non-traitée, l’agitation thermique suffit à déplacer les molécules d’ADN faiblement liées au mica, ce qui conduit à la formation de structures plus simples 1D. L’organisation est différente dans les solutions de Tris et d’HEPES. Dans la solution deTris, contenant des cations Mg2+, les arrangements conduisent à une architecture 2D, bien organisée. Dans la solution d’HEPES, contenant des cations Ni2+, la force ionique est 10 fois plus faible, qui conduit à une rupture des liaisons préalablement formées entre le mica et l'ADN. Cependant, les molécules d'ADN restent les unes près des autres en raison d'une substitution partielle des cations de Mg2+ déjà adsorbés par les cations de Ni2+ de plus grande affinité avec le mica. [...] / This work reports the various aspects of the application of atomic force microscopy (AFM), for the characterization of organic semiconductors and DNA-based arrays, for organic electronics and biological applications. On these soft surfaces, the amplitude modulation AFM mode was chosen. This choice is argued by a study of dissipative processes, performed on a particular sample, a DNA chip. We showed the influence of experimental parameters on the topographic and phase image quality. By calculating the dissipative energy, it was shown that the dissipation on the DNA chip was mainly induced by a viscoelastic tip-sample interaction.The AFM study of the "thickness-driven” pentacene growth was made to link the morphology to the nature of the substrate and to the electrical performance of created pentacene-based Organic Field Effect Transistor (OFET). Deposited on two polymer substrates, parylene and benzocyclobutene (BCB), pentacene has been characterized for nanoscale film thicknesses between 6 and 60nm. It has been shown that the larger grains were created for a deposited thickness of 30nm. Spectroscopic AFM mode was used as an alternative to the method of contact angles, to measure local surface energy. Decrease of surface energy is characteristic of a more ordered surface and was measured for a thickness of 30 nm of pentacene deposited on both substrates. Models of statistical analysis of spectral images, based on the Power Spectrum Distribution (PSD) have been used to explain the morphology of pentacene films. In addition, these models have provided a comprehensive description not only of the accessible surface of the sample, but also of its internal structural properties. Highlighted in the models, the critical thickness of 30 nm corresponds to a transition from the orthorhombic phase to the triclinic phase for pentacene molecules deposited on parylene. Similarly, a polymorphic transition occurs on the BCB. On OFETs, based on pentacene on BCB, the largest mobility of 3.1x10-2 cm²/Vs corresponds to the pentacene layer of 30nm, that shows a better ordering of the orthorhombic molecular packing in comparison with the triclinic packing.The molecular arrangement of X and Y structures based on DNA was observed, by AFM, in air and in two buffer solutions of Tris and HEPES on a mica substrate. It was shown that the treatment of the mica by Ni2 + ions increases the strength of the DNA/substrate interaction and reduces the diffusivity of the molecules. In air, wired macromolecules containing one double-stranded structure are observed on untreated mica and macromolecules with a 2D geometry on pretreated mica. Onto a non-treated, the greater thermal motion of weakly bounded to mica DNA molecules leads to the rupture of intermolecular bonding and the forming structures are more simple and not branched. The organization is different in solutions of Tris and HEPES. In the Tris solution, containing Mg2+ cations, the arrangement leads to a well-organized 2D architecture. In the HEPES solution, containing Ni2+ cations, the ionic strength is 10 times lower, this leads to a breaking of the bonds previously formed between DNA and mica. However, DNA molecules are near each other due to a partial substitution of already adsorbed Mg2 + cations by Ni 2 + cations of higher affinity with the mica. These results show that the two liquids promote a 2D assembly. In air, the networks are not stable and the few observed ones remain in a dendritic structure on the surface of pretreated mica and as a linear macromolecule on the untreated mica.

Ce travail de thèse porte sur l'étude de dérivés du pérylène-3,4:9,10-tétracarboxylique acide diimide comme semi-conducteurs pour l'électronique organique, et plus particulièrement pour la réalisation de transistors organiques à effet de champs. Les objectifs de ce travail sont la synthèse de dérivés du pérylène à l'aide entre autres de réactions d'halogénation ou de couplage de Suzuki-Miyaura, et la fabrication de transistors organiques à effet de champs. Dans un premier temps, une large gamme de dérivés du pérylène a été synthétisée et caractérisée. Des études spectroscopiques et électrochimiques ont pu être menées, notamment afin de déterminer les énergies des orbitales frontières de nos molécules. Puis dans un second temps, la réalisation de transistors organiques à effet de champs a été mise en oeuvre, en commençant par un gros travail d'optimisation des conditions de formulation des encres, de dépôt et de traitement du film. Puis ces transistors ont été caractérisés en mesurant les courants drain-source. Mots-clés : semi-conducteur, pérylène, transistor organique à effet de champs, couplage de Suzuki-Miyaura, impression jet d'encre. / This study deals with the synthesis of perylene-3,4:9,10-tetracarboxylic acid bisimide derivatives and their use as semi-conductors for organic electronics, and more specifically for the realization of organic field-effect transistors. The goals of this study are the synthesis of perylene derivatives, using halogenation reactions or Suzuki-Miyaura coupling, and the fabrication of organic field-effect transistors.In the first part of the work, a wide variety of perylene derivatives has been obtained and fully characterized. Spectroscopic and electrochemical studies have been performed to determine energy levels of the frontier orbitals.In the second part, the making of organic field-effect transistors was realized, beginning with the research of optimal conditions for ink formulation, deposition and annealing of the film. Then those devices have been characterized by measuring the source-drain current.Keywords: semi-conductor, perylene, organic field-effect transistor, Suzuki-Miyaura coupling, ink jet printing.

Les transistors organiques à effet de champ (OFETs) dans lesquels le transport des charges se fait à travers un film mince de molécules organiques représentent une transformation de la technologie des transistors à effet de champ au regard de la technologie au silicium. Ils permettent notamment d’envisager le développement d’une électronique flexible à bas coût. Ce travail porte sur la synthèse, l’étude et l’utilisation en tant que couche active dans des OFETs de type n de couples d’isomères para- et méta-indacénodithiophènes (para- et méta-IDT) appauvris en électrons inédits. Une introduction aux OFETs de type n est tout d’abord présentée. Elle est suivie par la présentation de la synthèse des dérivés IDT et de l’analyse comparée de leurs propriétés physico-chimiques. La fabrication des OFETs, leur caractérisation et l’optimisation de leur architecture est enfin décrite, leurs performances montrant l’intérêt des IDTs pour les OFETs de type n. Différentes fonctionnalisations menant à des IDTs d’architecture 3π-2spiro sont également synthétisées afin d’étudier les propriétés intrinsèques de ces dérivés π-conjugués et d’envisager leur incorporation comme matrice hôte dans des diodes électrophosphorescentes organiques. / Organic Field Effect Transistors (OFETs), in which the charge transport is carried through a thin film made of organic molecules represent a transformation of the FET technology regarding that based on Silicon. They offer in particular the possibility to manufacture low cost flexible electronics. This work is focused on the synthesis, the study and the use as active layer in n-type OFETs of novel, electron poor, couples of para- and meta-indacenodithiophenes isomers (para- and meta-IDT). First of all, an introduction to the field of n-type OFETs is presented, followed by the presentation of the synthesis of the IDT derivatives and the comparative analysis of their properties. Finally, the fabrication of the OFETs, their characterization and the optimization of their architecture is described. The performances recorded attest that these derivatives are of great interest for the n-type OFETs. Different 3π-2spiro IDT derivatives are also presented in order to study the IDTs intrinsic properties and to envisage their incorporation as host in phosphorescent organic light-emitting diodes.

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