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Les nanostructures périodiques jouent un rôle important dans le domaine des nanotechnologies, en particulier dans le contrôle des photons. Bien qu'il existe de nombreuses techniques d'usage général pour la fabrication et la simulation optique, nous avons développé une technique de fabrication sur mesure et une méthode de simulation optiques pour les structures périodiques pour accélérer le prototypage à l’échelle du laboratoire et la conception optique. Dans la première partie de cette thèse, nous décrivons une technique lithographique nommée « Laser Interference Lithography » (LIL) à faible coût pour la fabrication de nanostructures périodiques. La technique LIL est combinée avec gravure sèche, gravure humide et technique de gravure électrochimique pour réaliser, respectivement, des trous cylindriques, des pyramides inversées et des réseaux taux de pores bi-périodiques à facteur d’aspect élevé sur le substrat à base de silicium. Les modèles unidimensionnels sur des substrats en verre sont également utilisés comme nanofiltres dans la réalisation de la puce de pré-concentration à faible coût. Dans la deuxième partie, nous décrivons d'abord une méthode de calcul électromagnétique rigoureuse Rigorous Coupled-Wave Analysis (RCWA) conçu pour les structures périodiques. Une description détaillée est donnée pour expliquer la méthode numérique. Ensuite, nous combinons la méthode RCWA et une nouvelle approche proposée de la conception des modèles pseudo-désordonnée pour améliorer le piégeage des photons. A titre d'exemple, nous démontrons que, en ajoutant des structures désordonnées à petite échelle sur des arrangements périodiques à grande échelle, la performance quant à l’absorption des couches minces de silicium peut être grandement améliorée. / Periodic nanostructures play an important role in the domain of nanotechnology, especially in photon control. While there exist many general purpose techniques for fabrication and optical simulation, we show tailored fabrication and optical simulation methods for periodic structures to accelerate lab-scale prototyping and optical design. In the first part of this dissertation, we describe a low-cost lithographic technique named Laser Interference Lithography (LIL) for fabricating periodic nanostructures. LIL technique is combined with dry-etching, wet-etching and electrochemical etching technique to realize, respectively, cylindrical holes, inverted pyramids and high aspect ratio pore arrays on silicon based substrate. The one-dimensional patterns on glass substrates are also used as nanofilters in realizing low-cost preconcentration chip. In the second part, we first describe Rigorous Coupled-Wave Analysis (RCWA), a rigorous electromagnetic calculation method designed for periodic structures. A detailed derivation is given to explain the numerical method. Then, we combine the RCWA method and a new proposed pseudo-disordered patterns design approach to investigate photon control. As an example, we demonstrate that by adding ‘appropriate’ engineered fine stripes to each long period the absorption performance of thin silicon slab can be largely enhanced.

A new type of photolithography, Pattern-Integrated Interference Lithography (PIIL), was demonstrated. PIIL is the first-ever integration of pattern imaging with interference lithography in a single-exposure step. The result is an optical-intensity distribution composed of a subwavelength periodic lattice with integrated functional circuit elements. To demonstrate the PIIL method, a Pattern-Integrated Interference Exposure System (PIIES) was developed that incorporates a projection imaging capability in a novel three-beam interference configuration. The purpose of this system was to fabricate, in a single-exposure step, representative photonic-crystal structures. Initial experimental results have confirmed the PIIL concept, demonstrating the potential application of PIIL in nano-electronics, photonic crystals, biomedical structures, optical trapping, metamaterials, and in numerous subwavelength structures. In the design of the PIIES configuration, accurate motif geometry models were developed for the 2D plane-group symmetries possible via linearly-polarized three-beam interference, optimized for maximum absolute contrast and primitive-lattice-vector direction equal contrast. Next, a straightforward methodology was presented to facilitate a thorough analysis of effects of parametric constraints on interference-pattern symmetries, motif geometries, and their absolute contrasts. With this information, the design of the basic PIIES configuration was presented along with a model that simulates the resulting optical-intensity distribution at the system sample plane. Appropriate performance metrics were defined in order to quantify the characteristics of the resulting photonic-crystal structure.

This research comprehensively reviews the properties of regular micro and nano structures fabricated by laser interference lithography and reports on their applications in the antireflection and self‐cleaning surface. The research systematically investigates the laser interference lithography technology taking into account its advantages and abilities to realize various potential applications. Multiple‐beam interference lithography systems are constructed. Laser interference interaction with silicon wafer is analysed and the optical and hydrophobic properties are obtained via measurements. In order to fabricate the extremely low reflection and very large contact angle for solar cells, fabrication methods of antireflection and self‐cleaning are surveyed and their advantages and disadvantages compared. The research investigates the effect of heat transfer and the radiation of laser interference plasma on silicon wafer surfaces and proposes equations of heat flow and radiation effects of laser plasma of interfering patterns in a four‐beam laser interference distribution. Following the irradiation, the silicon wafer surface is covered with a periodic array of micrometer and nanometer‐sized structures, which have the shape of grating, cone and hole. The research also investigates the effect of different laser parameters on the optical and hydrophobic properties of the structured silicon wafer surface. The results of periodic hexagonally‐distributed hole structures fabricated by three‐beam laser interference reveals excellent design guidelines for obtaining an extremely low solar‐weighted reflection, (SWR, 1.86%) and relatively large contact angle (140°) which can provide a strong self‐cleaning capability on the solar cell surface. In addition, the research creates a novel dual structure with antireflection and superhydrophobic properties fabricated by three‐beam laser interference lithography. The fabrication method is three‐beam laser interference combined with focused laser processing interacting on the silicon wafer surface. This kind of structure has a very low SWR (3.6 %) and extremely large contact angle which is more than 150° in the wavelength range from 380 nm to 780 nm. The research shows that the laser interference lithography technology can be employed and further developed to fabricate micro and nano structures of strong antireflection and self‐cleaning functions for applications in solar cells.

<div>Fabrication of nanoscale highly periodic structures is a vital capability for research on quasicrystals, directional and specular selective emitters, and plasmonics. Laser interference lithography is a maskless lithography process capable of producing patterns with high periodicity over large areas, and is compatible with standard optical lithography processing. In this work, a Lloyd's mirror lithographic interferometer is simulated, built, and tested. Featuring a HeCd CW laser at 325 nm, spatial lter, and vacuum stage, it is capable of generating patterns with a sub-100 nanometer half pitch, over a large area (approximately 8 cm²), with minimal distortion, in a single exposure; with 2D patterns possible using multiple exposures. The interferometer features a compact sliding enclosure, simple alignment and operation, and quick adjustments to the desired period. One-dimensional and two-dimensional patterns were generated and matched well with simulation.</div>

Nous avons étudié théoriquement et expérimentalement la formation de réseaux en relief sur des surfaces active ou passive, avec deux types de polymères photosensibles : résine photosensible négative et copolymère azobenzene. Le mécanisme de formation des structures est attribué à l'effet de transport de masse, qui déplace la matière dans des directions opposées dans ces deux matériaux. La technique de fabrication est basée sur l'utilisation de la lithographie par interférence, ce qui a permis de créer des structures grandes et uniformes. Dans le premier cas, des structures passives de surface en relief en 1D et 2D ont été créés sur la résine photosensible négative SU8 grâce à l'effet de rétrécissement durant le processus de réticulation. Dans le second cas, des structures périodiques actives en 1D, 2D et 3D ont été obtenues grâce à la migration des matériaux copolymères DR1/PMMA des régions de forte intensité d’irradiation à celles de faible intensité. L'amplitude de modulation de la structure est optimisée par le contrôle de l'épaisseur du film, de la périodicité de la structure, de la dose d'exposition, et des polarisations des faisceaux laser. Les applications de ces structures pour des lasers DFB à multiples longueurs d'onde, les cristaux photoniques non-Linéaires, et le couplage dans les guides d'ondes ont été discutés. / We have theoretically and experimentally investigated the formation of both active and passive surface relief gratings on two kinds of photosensitive polymers: negative photoresist and azobenzene copolymer. The common mechanism of the structures formation was attributed to mass transport effect, which however pushes the materials in opposite directions in these two materials. The fabrication technique is based on the use of interference lithography, which allowed to create large and uniform structures. In the first case, 1D and 2D passive periodic surface relief structures were created on the negative photoresist SU8 thanks to the shrinkage effect during the crosslinking process. In the second case, 1D, 2D and 3D active periodic structures have been obtained thanks to the movement of DR1/PMMA copolymer materials from regions of high intensity to those of low intensity irradiation. The modulation amplitude of structures is optimized by controlling the film thickness, the structure periodicity, the exposure dosage, and the polarizations of interference laser beams. Applications of these structures for multiple wavelength DFB laser, nonlinear photonic crystals, and waveguide coupling have been discussed.

The image quality and collimation in a multiple-optical-axis pattern-integrated interference lithography system are evaluated for an elementary optical system composed of single-element lenses. Image quality and collimation are individually and jointly optimized for these lenses. Example images for a jointly optimized system are simulated using a combination of ray tracing and Fourier analysis. Even with these non-optimized components, reasonable fidelity is shown to be possible.

Disertacijos tikslas buvo sukurti metodą periodinių darinių formavimui interferencinės litografijos būdu, polimerizuojant fotojautrias medžiagas, eksperimentiškai ištirti šio metodo galimybes ir ribojimus bei suformuoti mikrodarinius, tinkamus praktiniams taikymams. Eksperimentų metu buvo pademonstruota, kad interferencinės litografijos metodu formuojamų mikrodarinių forma priklauso nuo: lazerinės apšvitos dozės, bangos ilgio, fazės, kampo tarp interferuojančių pluoštų ir pluoštų skaičiaus, o jų tvirtumas labiausiai priklauso nuo lazerinės apšvitos dozės. Šiame darbe taip pat parodyta, kad naudojant interferencinės litografijos metodą viena lazerine ekspozicija galima formuoti mikrovamzdelių ir mikrolęšių masyvus bei karkasus iš biosuderinamos ir biosuskaidomos PEG-DA-258 medžiagos. Be polimerinių darinių formavimo, šiame darbe pademonstruota ir jų fotomodifikavimo galimybė, naudojant fotoįskiepijimo (angl. photo-grafting) technologiją, o taip pat realizuojant variu katalizuojamos azido alkino ciklizacijos (CuAAC) cheminę reakciją parodyta fotoįskiepijimo technologijos ir „klik“ chemijos apjungimo galimybė. Toks paprastas ir universalus būdas atveria naujas galimybes biojutiklių kūrime ir audinių inžinerijoje, nes molekulių imobilizavimas polimero matricoje vyksta trimatėje erdvėje ir tiksliai norimoje vietoje, o trimatė erdvinė gradientinė kontrolė yra labai svarbi daugybėje biotechnologijos taikymų. / The main aim of this work was to develop the formation technique of periodic micro-structures by interference lithography in photosensitive polymeric materials, experimentally investigate possibilities and limitations of the method, and to create micro-structures suitable for practical applications. The shape of the micro-structures fabricated by interference lithography depends on the used laser irradiation dose, laser wavelength, phase, polarization, the angle between interfering beams and the number of the interfering beams, and their rigidity - mainly on the used laser irradiation dose. In this work also the possibility to form micro-tube and scaffolds arrays by using interference lithography was demonstrated and the control of the geometrical parameters of micro-lenses fabricated by interference lithography and manipulating the laser irradiation dose was investigated in depth. The possibility to immobilize the newly synthesized aromatic azides molecules in PEG matrix by photo-grafting technique was also demonstrated and the copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) chemical reaction by using azide “MegaStokes dye 673” was realized, in order to show the capability to combine the photo-grafting technique with “click” chemistry. The developed 3D site-specific functionalization method is simple and versatile; it has potential applications in micro-array based proteome analysis, studies of cell-surface interactions, sensing applications, and drug screening.

The main aim of this work was to develop the formation technique of periodic micro-structures by interference lithography in photosensitive polymeric materials, experimentally investigate possibilities and limitations of the method, and to create micro-structures suitable for practical applications. The shape of the micro-structures fabricated by interference lithography depends on the used laser irradiation dose, laser wavelength, phase, polarization, the angle between interfering beams and the number of the interfering beams, and their rigidity - mainly on the used laser irradiation dose. In this work also the possibility to form micro-tube and scaffolds arrays by using interference lithography was demonstrated and the control of the geometrical parameters of micro-lenses fabricated by interference lithography and manipulating the laser irradiation dose was investigated in depth. The possibility to immobilize the newly synthesized aromatic azides molecules in PEG matrix by photo-grafting technique was also demonstrated and the copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) chemical reaction by using azide “MegaStokes dye 673” was realized, in order to show the capability to combine the photo-grafting technique with “click” chemistry. The developed 3D site-specific functionalization method is simple and versatile; it has potential applications in micro-array based proteome analysis, studies of cell-surface interactions, sensing applications, and drug screening. / Disertacijos tikslas buvo sukurti metodą periodinių darinių formavimui interferencinės litografijos būdu, polimerizuojant fotojautrias medžiagas, eksperimentiškai ištirti šio metodo galimybes ir ribojimus bei suformuoti mikrodarinius, tinkamus praktiniams taikymams. Eksperimentų metu buvo pademonstruota, kad interferencinės litografijos metodu formuojamų mikrodarinių forma priklauso nuo: lazerinės apšvitos dozės, bangos ilgio, fazės, kampo tarp interferuojančių pluoštų ir pluoštų skaičiaus, o jų tvirtumas labiausiai priklauso nuo lazerinės apšvitos dozės. Šiame darbe taip pat parodyta, kad naudojant interferencinės litografijos metodą viena lazerine ekspozicija galima formuoti mikrovamzdelių ir mikrolęšių masyvus bei karkasus iš biosuderinamos ir biosuskaidomos PEG-DA-258 medžiagos. Be polimerinių darinių formavimo, šiame darbe pademonstruota ir jų fotomodifikavimo galimybė, naudojant fotoįskiepijimo (angl. photo-grafting) technologiją, o taip pat realizuojant variu katalizuojamos azido alkino ciklizacijos (CuAAC) cheminę reakciją parodyta fotoįskiepijimo technologijos ir „klik“ chemijos apjungimo galimybė. Toks paprastas ir universalus būdas atveria naujas galimybes biojutiklių kūrime ir audinių inžinerijoje, nes molekulių imobilizavimas polimero matricoje vyksta trimatėje erdvėje ir tiksliai norimoje vietoje, o trimatė erdvinė gradientinė kontrolė yra labai svarbi daugybėje biotechnologijos taikymų.

Ce travail porte sur la fabrication des structures photoniques (SPs) à base de polymères etleurs applications en optique non-linéaire. Dans la première partie, nous avons démontré lafabrication des SPs souhaitées par la méthode d’interférence. En particulier, l’interférencede deux faisceaux laser avec une exposition multiple est démontrée théoriquement etexpérimentalement comme un meilleur choix pour la fabrication des structures souhaitées,qui sont uniformes et de grande taille. Diverses structures à 1D, 2D, et 3D, périodiques etquasi-périodiques sont fabriquées avec succès dans la résine SU8. Nous avons égalementdémontré un moyen pour surmonter l’effet d’absorption de la photorésine, qui impose unelimitation de l’épaisseur des structures, en ajoutant un faisceau laser uniforme en sensopposé par rapport à deux faisceaux d’interférence. Les SPs fabriquées deviennent plusuniformes et leur épaisseur augmente jusqu’à 25 μm. Une autre approche utilisant laméthode d’absorption ultra-faible à un photon a également été mise en oevre montrant lapossibilité d’obtenir des SPs avec une épaisseur jusqu’à 600 μm. De plus, en utilisant latechnique d’interférence et l’effet de transport de masse, nous avons également démontré lafabrication des structures à relief de surface (SRG), avec une profondeur contrôlable, dansdes polymères passives (SU8) et des polymères actives (DR1/PMMA). Dans la deuxièmepartie, nous avons utilisé ces structures pour l’amélioration de la génération de secondeharmonique des matériaux polymères par deux manières différentes: quasi-accord de phase(QPM) et mode de résonance de guide d’onde (WRG). Les structures de QPM permet desurmonter le déphasage entre les ondes fondamentale et harmonique, et par conséquenceaugmente le rendement du taux de conversion. En outre, les structures de guide d’ondeavec une surface modulée (WRG) ont également été démontrées comme une excellenteméthode permettant d’amplifier le signal de SHG par un facteur de 25. / This dissertation deals with the fabrication of various polymer-based photonic structures(PSs) and their applications in nonlinear optics. In the first part, we have demonstratedthe fabrication of desired PSs by interference lithography technique. The two-beam interferencemethod is theoretically and experimentally demonstrated as a best choice forfabrication of all kinds of PSs with large and uniform area. Desired 1D, 2D, and 3D,periodic and quasi-periodic PSs are successfully fabricated on SU8 photoresist. We alsodemonstrated a way to overcome the material’s absorption effect, which imposes a limitationof PSs thickness. By adding one more exposure of a uniform laser beam in oppositedirection of two interfering beams, the fabricated PSs became more uniform and theirthickness increased to 25 μm. A tentative of using low one-photon absorption techniquewas also realized showing the possibility to obtain a PS with a thickness upto 600 μm.Furthermore, by using the interference technique combined with mass transport effect,we have demonstrated the fabrication of desired surface relief grating structures, with acontrollable depth, on passive polymer (SU8) and active polymer (DR1/PMMA). In thesecond part, we applied these fabricated structures for enhancement of nonlinearity ofpolymer materials by two different ways: quasi-phase-matching (QPM) and waveguideresonance grating (WRG). Both theoretical calculation and experimental realization ofthese techniques have been investigated. The QPM structures allowed to overcome thephase mismatch of fundamental and harmonic waves, thus increasing the conversion efficiency.The second-harmonic generation (SHG), one of the most important applicationsof frequency conversion, is significantly enhanced thanks to the QPM condition. Anothermethod basing on the WRG structures allowed to increase the intensity of fundamentalwave, thus enhancing the SHG signal by a factor of 25.