Relevant bibliographies by topics / DIRECT LASER WRITING LITHOGRAPHY

Academic literature on the topic 'DIRECT LASER WRITING LITHOGRAPHY'

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Published: 10 March 2023

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Journal articles on the topic "DIRECT LASER WRITING LITHOGRAPHY"

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Rensch, Clemens, Stefan Hell, Manfred v. Schickfus, and Siegfried Hunklinger. "Laser scanner for direct writing lithography." Applied Optics 28, no. 17 (September 1, 1989): 3754. http://dx.doi.org/10.1364/ao.28.003754.

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Ulrich, H., R. W. Wijnaendts-van-Resandt, C. Rensch, and W. Ehrensperger. "Direct writing laser lithography for production of microstructures." Microelectronic Engineering 6, no. 1-4 (December 1987): 77–84. http://dx.doi.org/10.1016/0167-9317(87)90019-0.

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Ni, Haibin, Guanghui Yuan, Liangdong Sun, Ning Chang, Di Zhang, Ruipeng Chen, Liyong Jiang, Hongyuan Chen, Zhongze Gu, and Xiangwei Zhao. "Large-scale high-numerical-aperture super-oscillatory lens fabricated by direct laser writing lithography." RSC Advances 8, no. 36 (2018): 20117–23. http://dx.doi.org/10.1039/c8ra02644k.

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Guney, M. G., and G. K. Fedder. "Estimation of line dimensions in 3D direct laser writing lithography." Journal of Micromechanics and Microengineering 26, no. 10 (September 7, 2016): 105011. http://dx.doi.org/10.1088/0960-1317/26/10/105011.

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Sun, Hong-Bo, Atsushi Nakamura, Koshiro Kaneko, Satoru Shoji, and Satoshi Kawata. "Direct laser writing defects in holographic lithography-created photonic lattices." Optics Letters 30, no. 8 (April 15, 2005): 881. http://dx.doi.org/10.1364/ol.30.000881.

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Harke, Benjamin, Paolo Bianchini, Fernando Brandi, and Alberto Diaspro. "Photopolymerization Inhibition Dynamics for Sub-Diffraction Direct Laser Writing Lithography." ChemPhysChem 13, no. 6 (March 5, 2012): 1429–34. http://dx.doi.org/10.1002/cphc.201200006.

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Wang Hongqing, 王洪庆, 温积森 Wen Jisen, 杨臻垚 Yang Zhenyao, 汤孟博 Tang Mengbo, 孙秋媛 Sun Qiuyuan, 马程鹏 Ma Chengpeng, 王子昂 Wang Ziang, et al. "高速并行双光子激光直写光刻系统." Chinese Journal of Lasers 49, no. 22 (2022): 2202009. http://dx.doi.org/10.3788/cjl202249.2202009.

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Hu, Jin, D. L. Pu, and Lin Sen Chen. "The Deep Etching Process Based on Parallel Laser Direct Writing System." Key Engineering Materials 426-427 (January 2010): 265–69. http://dx.doi.org/10.4028/www.scientific.net/kem.426-427.265.

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Due to the high cost-effectiveness, extra flexibility, and short production cycle, laser direct writing system as a kind of maskless lithography technology has been widely used in the fields of micro-nano-manufacturing. The working principle of the parallel laser direct writing system based on DMD(Digital Micromirror Device) is introduced. A novel negative photoresist -- dry film photoresist is adopted into the study of deep etching for the fabrication of the micro mold. The experimental results show that: the whole process is convenient, efficient and flexible; the precision of the 2-D patterning and the depth of etching is reliable.
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Yuan, Chenyu, Jukun Liu, Tianqing Jia, Kan Zhou, Hongxin Zhang, Jia Pan, Donghai Feng, and Zhenrong Sun. "Super resolution direct laser writing in ITX resist inspired by STED microscopy." Journal of Nonlinear Optical Physics & Materials 23, no. 02 (June 2014): 1450015. http://dx.doi.org/10.1142/s0218863514500155.

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Direct laser writing (DLW) has become a routine tool for fabricating microstructures through two photon polymerization. Due to the diffraction limit, the resolution is usually larger than a quarter of a wavelength. In this article, by using stimulated emission depletion (STED) inspired lithography, we fabricate nanodot of 81 nm in diameter and nanoline of 93 nm in width in resist with initiator of isopropyl thioxanthone (ITX). An 800 nm, 75-MHz fs laser works as the polymerization light and a 532 nm donut mode continuous wave (CW) laser as the depletion light. This technology is potentially useful for fabrication of super resolution nanostructures.
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Cara, Eleonora, Federico Ferrarese Lupi, Matteo Fretto, Natascia De Leo, Mauro Tortello, Renato Gonnelli, Katia Sparnacci, and Luca Boarino. "Directed Self-Assembly of Polystyrene Nanospheres by Direct Laser-Writing Lithography." Nanomaterials 10, no. 2 (February 7, 2020): 280. http://dx.doi.org/10.3390/nano10020280.

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In this work, we performed a systematic study on the effect of the geometry of pre-patterned templates and spin-coating conditions on the self-assembling process of colloidal nanospheres. To achieve this goal, large-scale templates, with different size and shape, were generated by direct laser-writer lithography over square millimetre areas. When deposited over patterned templates, the ordering dynamics of the self-assembled nanospheres exhibits an inverse trend with respect to that observed for the maximisation of the correlation length ξ on a flat surface. Furthermore, the self-assembly process was found to be strongly dependent on the height (H) of the template sidewalls. In particular, we observed that, when H is 0.6 times the nanospheres diameter and spinning speed 2500 rpm, the formation of a confined and well ordered monolayer is promoted. To unveil the defects generation inside the templates, a systematic assessment of the directed self-assembly quality was performed by a novel method based on Delaunay triangulation. As a result of this study, we found that, in the best deposition conditions, the self-assembly process leads to well-ordered monolayer that extended for tens of micrometres within the linear templates, where 96.2% of them is aligned with the template sidewalls.
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Dissertations / Theses on the topic "DIRECT LASER WRITING LITHOGRAPHY"

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Buse, Hauke. "Micro- and sub-microstructuring and characterisation of technical surfaces by means of laser direct writing including a novel approach for laser beam profiling." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8361.

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Within recent years, numerous fields of engineering, like mechanics, optics and electronics, have been influenced and revolutionised by the technique of microand nano-structuring. For example, special optical elements for beam shaping, surface structures for the reduction of friction or modern "lab on chip" devices have been produced. Within this thesis a universal system has been developed facilitating the production of such structured surfaces with dimensions down to 500 nm. This system is not only capable of structuring surfaces by means of lithographic processes; it further allows the inspection of surfaces by scanning their topography. To realise such a system, two different technologies have been evaluated: Scanning Near-field Optical Lithography (SNOL), a very sophisticated technique which uses a thin fibre tip to expose a photo resist-covered surface, and confocal scanning technology. Here, the confocal scanning is accomplished using an adapted optical component, the optical pickup unit (OPU), from a gaming console, which turned out to be the most suitable and cost-efficient solution for the realisation of this system. Several test series have been carried out during this work, to verify the performance of the confocal system, both to structure photo resist surfaces and to characterise unknown surfaces. This present work will show the ability of the developed system to produce structures down to the sub-micron range and to characterise unknown surfaces with sub- micron precision. Various patterns have been written into photo resistcoated substrates to structure their surface. Beginning with diffractive optical elements (DOE) for beam shaping, followed by Dammann gratings for twodimensional beam shaping and optical gratings for light guidance as well as producing technical surfaces imitating the properties of sharkskin or simple micromechanical structures, the developed confocal system has shown itself to be flexible and widely-applicable. IV During the development of the confocal system, a strong need for a beam profiling system analysing the light beam diverging from the OPU, was recognised. Due to the fact that no commercially available system was capable of characterising beam sizes within the range of the diffraction limit, a novel method for beam profiling was invented. This method makes use of the fibre tips already applied within the SNOL system, producing tomographical scans of the beam spot.
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Bagheri, Shahin [Verfasser], and Harald [Akademischer Betreuer] Giessen. "Large-area plasmonics and sensors : fabrication of plasmonic nanostructures by laser interference lithography and femtosecond direct laser writing / Shahin Bagheri ; Betreuer: Harald Giessen." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2017. http://d-nb.info/1132583144/34.

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Abou, Khalil Alain. "Direct laser writing of a new type of optical waveguides and components in silver containing glasses." Doctoral thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/33849.

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"Thèse en cotutelle, Doctorat en physique; Université Laval, Québec, Canada et Université de Bordeaux, Talence, France"
L'inscription laser directe est un domaine de recherche en croissance depuis ces deux dernières décennies, fournissant un moyen efficace et robuste pour inscrire directement des structures en trois dimensions (3D) dans des matériaux transparents tels que des verres en utilisant des impulsions laser femtosecondes. Cette technique présente de nombreux avantages par rapport à la technique de lithographie, qui se limite à la structuration en deux dimensions (2D) et implique de nombreuses étapes de fabrication. Cela rend la technique d’inscription laser directe bien adaptée aux nouveaux procédés de fabrication. Généralement, l’inscription laser dans les verres induit des changements physiques tels qu'un changement permanent de l'indice de réfraction localisé. Ces modifications ont été classées en trois types distincts:(type I, type II et type III). Dans ce travail, nous présentons un nouveau type de changement d'indice de réfraction, appelé type A qui est basé sur la création d’agrégats d'argent photo-induits. En effet, dans des verres dans lesquels sont incorporés des ions argent Ag+, lors de leur synthèse, l’inscription laser directe induit la création d’agrégats d’argent fluorescents Agmx+ au voisinage du voxel d’interaction. Ces agrégats modifient localement les propriétés optiques comme la fluorescence, la non-linéarité et la réponse plasmonique du verre. Ainsi, différents guides d'ondes, un séparateur de faisceau 50-50, ainsi que des coupleurs optiques ont été inscrits en se basant sur ce nouveau type A et complétement caractérisés. D'autre part, une étude comparative entre les deux types de guides d'ondes (type A et type I) est présentée, tout en montrant qu’en ajustant les paramètres laser, il est possible de déclencher soit le type I soit le type A. Enfin, en se basant sur des guides d’ondes de type A inscrits proche de la surface du verre, un capteur d'indice de réfraction hautement sensible a été inscrit dans une lame de verre de 1 cm de long. Ce capteur miniaturisé peut présenter deux fenêtres de détection d’indice, ce qui constitue une première mondiale. Les propriétés des guides d'ondes inscrits dans ces verres massifs ont été transposées à des fibres en forme de ruban, du même matériau contenant de l'argent. Les résultats obtenus dans ce travail de thèse ouvrent la voie à la fabrication de circuits intégrés en 3D et de capteurs à fibre basés sur des propriétés optiques originales inaccessibles avec des guides d’onde de type I standard.
Direct Laser Writing (DLW) has been an exponentially growing research field during the last two decades, by providing an efficient and robust way to directly fabricate three dimensional (3D) structures in transparent materials such as glasses using femtosecond laser pulses. It exhibits many advantages over the lithography technique, which is mostly limited to two dimensional (2D) structuring and involves many fabrication steps. This competitive aspect makes the DLW technique suitable for future technological transfer to advanced industrial manufacturing. Generally, DLW in glasses induces physical changes such as permanent local refractive index modifications that have been classified under three distinct types: (Type I, Type II & Type III). In silver containing glasses with embedded silver ions Ag+, DLW induces the creation of fluorescent silver clusters Agmx+ at the vicinity of the interaction voxel. In this work, we present a new type of refractive index change, called type A occurring in the low pulse energy regime that is based on the creation of the photo-induced silver clusters allowing the creation of new linear and nonlinear optical waveguides in silver containing glasses. Various waveguides, a 50- 50 Y beam splitter, as well as optical couplers, were written based on type A modification inside bulk glasses and further characterized. In addition, a comparitive study between type A and type I waveguides is presented, showing that finely tuning the laser parameters allows the creation of either type A or type I modifications inside silver containing glasses. Finally, based on type A near-surface waveguides, a highly sensitive refractive index sensor is created in a 1 cm glass chip, which could exhibit a pioneer demonstration of double sensing refractive ranges. The waveguiding properties observed and reported in the bulk of such silver containing glasses were transposed to ribbon shaped fibers of the same material. Those results pave the way towards the fabrication of 3D integrated circuits and fiber sensors with original fluorescent, nonlinear and plasmonic properties that are not accessible using the standard type I modification.
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Florian, Baron Camilo. "Laser direct-writing for microfabrication." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/400403.

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Digital manufacturing constitutes a real industrial revolution that is transforming the production processes from the early stages of research and development to mass production and marketing. The biggest difference in comparison with old fabrication methods is the possibility to perform changes in the pattern design just by using mouse clicks instead of modifying an already fabricated prototype, which results in faster, cheaper and more efficient fabrication processes. For example, new technologies enabling the production of printed electronic devices on flexible substrates and compatible with roll-to-roll processing methods would result in cheaper fabrication costs than the traditional batch processing of silicon wafers. Such fabrication methods comprise a series of processing steps which are applied to the substrates while they are moving on rolls in the fabrication line. Therefore, it is desired that the new technologies can work at high speeds allowing at the same time the production of miniaturized features. Lasers are a versatile tool that can meet the demands of flexibility, speed, resolution and compatibility with roll-to-roll processing of digital manufacturing. The main advantages of laser radiation rely in its unique properties: high directionality, coherence and monochromaticity. The combination of such properties allows generating high intensities that can be focused into extremely small volumes, which makes lasers an ideal tool for the processing of materials at the micro- and nano-scale, not only as a subtractive but also as an additive technique. Laser ablation is the best known subtractive technique and it consists in the irradiation of a material with a focused laser beam. In the case of working with transparent materials, surface ablation constitutes a serious challenge since it is necessary to develop new strategies that allow controlling the position where the energy is delivered to ensure that ablation really occurs in the surface without modifying the bulk material. On the other hand, lasers can also be used as additive tools. For example, laser-induced forward transfer (LIFT) allows the transfer of materials in both solid and liquid state with high spatial resolution. In spite of the extensive amount of research on LIFT, some challenges still remain. For instance, the understanding of the particular printing dynamics encountered during the high speed printing of liquids, or the problem of printing uniform, continuous and stable lines with high spatial resolution. The objective of this thesis is to propose and implement feasible solutions to some of the challenges that are associated with both the subtractive and additive laser based techniques presented above. On one side, we study the laser ablation of transparent polymers using femtosecond laser pulses with the aim of achieving spatial resolutions that overcome the diffraction limit, and at the same time solving the problem of the required precise focusing of the laser beam on the materials surface. On the other side, we study the LIFT transfer dynamics during the high speed printing of liquids, and we propose alternative printing strategies to solve the inherent quality defects usually encountered during the formation of printed lines. Finally, two different approaches that are a combination of both subtractive and additive techniques are presented; we implement LIFT for the fabrication of liquid microlenses used for the surface nanopatterning of materials, and on the other side, we create fluidic guides by laser ablation for the printing of high quality continuous lines.
La fabricació digital de dispositius tecnològics requereix el desenvolupament de noves i millors tècniques per al microprocessament de materials que al mateix temps siguin compatibles amb mètodes de producció en sèrie a gran escala com el roll-to-roll processing. Aquestes tècniques han de complir certs requisits relacionats amb la possibilitat de realitzar canvis de disseny ràpids durant el procés de fabricació, alta velocitat de processament, i al mateix temps permetre la producció de motius de forma controlada amb altes resolucions espacials. En la present tesi es proposen i implementen solucions viables a alguns dels reptes presents a la microfabricació amb làser tant substractiva com additiva. D'una banda, es presenta un nou mètode d'enfocament del feix làser sobre la mostra per l'ablació superficial de materials transparents que permet obtenir resolucions espacials que superen el límit de difracció del dispositiu òptic. D'altra banda, es duu a terme un estudi de la dinàmica de la impressió de líquids mitjançant làser a alta velocitat, de gran interès de cara a la implementació industrial de la tècnica. A més, es presenten estratègies d'impressió de tintes conductores amb l'objectiu de produir línies contínues amb alta qualitat d'impressió. Finalment s'inclouen dues propostes que són producte de la combinació d’ambues tècniques, la impressió de líquids i l'ablació amb làser.
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Heathcote, Robert. "Synthesis and application of organogold precursors for direct laser writing." Thesis, Keele University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502939.

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Park, Chang-Hyun. "Study on nonlinear multi-dimensional direct laser writing by using ultrashort high power laser." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0046.

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Au cours des 30 dernières années, alors que la largeur d'impulsion des lasers a été réduite et que les lasers haute puissance ont été développés, des recherches sur l'interaction entre le photon et les matériaux utilisant des lasers femtosecondes ont été activement menées. La haute densité d'énergie des lasers pulsés femtosecondes permet des processus de photoionisation non linéaire de plusieurs manières selon. Cet article rapporte une étude d'une écriture laser directe de type Argentum dans des verres de phosphate de zinc contenant de l'argent en induisant une déformation d'absorption non linéaire d'impulsions laser femtoseconde. Lorsque des verres de phosphate de zinc contenant de l'argent sont irradiés avec des impulsions laser femtoseconde, des amas en forme d'anneau se forment en raison d'une absorption non linéaire. Les propriétés de fluorescence et l'indice de réfraction de l'amas d'argent induit par cette déformation sont différents de ceux du verre d'origine.Des comparaisons simultanées de microsondes chimiques, de NSOM et de modélisation numérique ont été utilisées pour analyser la distribution des espèces d'argent induite par laser. Les résultats renforcent considérablement la compréhension des modifications matérielles de ces verres dans un régime d'interaction non thermique. En particulier, il a été constaté que la distribution spatiale des espèces dans des verres contenant de l'argent produits par irradiation laser femtoseconde a un effet significatif sur la sélectivité de la gravure chimique.Les séparateurs de faisceau en forme de Y, des structures 2D fabriquées à l'aide de DLW de type A, ont été fabriqués et leurs performances ont été mesurées. Il a été confirmé qu'un guide d'onde de forme générale dans laquelle l'indice de réfraction du noyau est plus grand que celui du revêtement peut être produit par le biais d'un DLW de type A. Étant donné que le DLW de type A induit toujours des changements d'indice de réfraction positifs de 2,7 x 10-3 à 5,1 x 10-3, il est très approprié pour fabriquer un guide d'onde. Une jonction Y symétrique et diverses jonctions Y asymétriques ont été conçues et fabriquées à l'aide de guides d'ondes à double ligne, et les rapports de sortie ont été mesurés en fonction de la transition de la position d'injection. Il a été confirmé que le ratio de sortie pourrait être de 96% -4% à 57% -43% en raison de l'irradiance différente dans le processus d'écriture entre la branche supérieure et la branche inférieure. Ainsi, les verres DLW en argent contenant du phosphate de zinc peuvent être utilisés facilement et rapidement pour fabriquer le type de dispositif optique souhaité avec uniquement le processus d'écriture.Enfin, en recherchant le stockage optique de données 5D (ODS) à l'aide de DLW de type A, le champ d'application a été élargi. Nous avons démontré le stockage optique de données 5D encodé dans des modifications orientées DLW de type A en utilisant un rayonnement laser relativement faible par rapport au DLW conventionnel. Cinq dimensions ont été obtenues en ajoutant l'orientation du motif d'ellipse et l'intensité de fluorescence à la position 3D. Le motif d'ellipse a été créé par mise au point anamorphique, et l'orientation a été ajustée à 16 niveaux en utilisant SLM. De plus, un dispositif AOM a été utilisé pour régler l'irradiance laser femtoseconde de 16 niveaux.Pour confirmer la possibilité du 5D ODS proposé, deux images différentes ont été simultanément intégrées dans une image par DLW de type A. Et les deux images originales différentes au format bitmap 4 bits ont été restaurées avec succès. Les fidélité de lecture correspondantes de 60,5% et 25,1% ont été obtenues pour la direction d'orientation et les niveaux d'intensité de fluorescence, respectivement. De plus, il est démontré que la précision de lecture peut être considérablement améliorée à 85,0% et 47,1% lorsque le format bitmap 3 bits a été appliqué. [...]
In the past 30 years as the pulse width of lasers has been narrowed and high-power lasers have been developed, researches on the interaction between photon and materials using femtosecond lasers have been actively conducted. The high energy density of femtosecond pulsed lasers enables nonlinear photoionization processes in several ways depending. This paper reports a study of a type Argentum direct laser writing in silver containing zinc phosphate glasses by inducing a nonlinear absorption deformation of femtosecond laser pulses. When silver-containing zinc phosphate glasses are irradiated with femtosecond laser pulses, ring-shaped clusters are formed due to non-linear absorption. The fluorescence properties and the refractive index of the silver cluster induced by this deformation are different from those of the original glass.Simultaneous comparisons of chemical micro probes, NSOM and numerical modeling were used to analyze the laser-induced silver species distribution. The results significantly strengthen the understanding of material modifications in such glasses in a non-thermal interaction regime. In particular, it has been found that the spatial distribution of species in silver-containing glasses produced by femtosecond laser irradiation has a significant effect on chemical etching selectivity.The Y-shaped beam splitters, 2D structures made by using type A DLW, was fabricated and its performance was measured. It was confirmed that a waveguide of a general shape in which the refractive index of the core is larger than that of cladding can be produced through type A DLW. Since the type A DLW always induces positive refractive index changes from 2.7x10-3 to 5.1x10-3, it is very suitable for making waveguide. A symmetric Y-junction and various asymmetric Y-junctions were designed and fabricated using double line waveguides, and the output ratios were measured according to the transition of the inject position. It was confirmed that the output ratio could be from 96%-4% to 57%-43% due to the different irradiance in the process of writing between the upper branch and lower branch. So DLW in silver containing zinc phosphate glasses can be utilized easily and quickly to fabricate the desired type of optical device with only the writing process.Finally, by researching 5D optical data storage (ODS) using type A DLW, the scope of application was further expanded. We have demonstrated 5D optical data storage encoded in orientated type A DLW modifications by using a relatively low laser irradiance compared to conventional DLW. Five dimensions were achieved by adding the orientation of ellipse pattern and fluorescence intensity to 3D position. The ellipse pattern was created by anamorphic focusing, and the orientation was adjusted to 16 levels by employing SLM. In addition, AOM device was used to adjust the femtosecond laser irradiance of 16 levels.To confirm the possibility of the proposed 5D ODS, two different images were simultaneously embedded in one image by type A DLW. And the two different original images of 4-bit bitmap format were successfully restored. The corresponding reading fidelities of 60.5% and 25.1% were obtained for the orientation direction and fluorescence intensity levels, respectively. In addition, it is shown that the reading accuracy can be greatly improved to 85.0% and 47.1% when 3-bit bitmap format was applied. Using the proposed this technology, we have reached a maximum data density of 14.9 Gb/cm3, and we believe that data storage densities of up to 119.2 Gb/cm3 (using NA = 1.3 oil target) can be achieved.In conclusion, the fluorescence characteristics of type A DLW in silver containing zinc phosphate glasses were studied, and its utility as a multi-dimension application was confirmed. We believe this technology has great potential for nano-scale patterning in semiconductor and fabrication of micro-scale optical devices
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Tian, Jing. "Femtosecond laser direct writing of circular optical properties in silica glass." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASF038.

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L'écriture directe par laser femtoseconde (FLDW) permet de créer des modifications permanentes fortement localisées en 3D dans les matériaux transparents. Certains aspects de l'interaction lumière-matière sont fondamentalement nouveaux. Ici, la matière et la lumière sont en interaction produisant une auto-organisation structurée du plasma en cohérence le faisceau laser et ses propriétés vectorielles. Après l'impulsion, cette distribution de densité électronique est "imprimée" en piégeant des électrons dans le solide et un champ de contraintes local peut même être stocké. Celle-ci peut être utilisée comme source par l'impulsion suivante assurant ainsi un « effet mémoire ». Dans cette opération, le solide est restructuré par le champ de force créé par le laser. On peut donc imaginer l'orientation des modifications structurales telles que la décomposition d'oxydes solidifiés directionnellement, la formation de nanocristaux orientés ou encore la création de structures chirales. C'est une nouvelle physique. Mais pour la chimie aussi, il y a de nouveaux aspects car les processus passent par des états fortement excités, largement hors équilibres. Il est donc nécessaire de remettre en question certaines idées précédentes pour comprendre l'excitation et la relaxation de la matière puis de contrôler la structure du produit. Récemment, ces propriétés ont été exploitées avec succès pour de multiples applications pratiques, notamment des optiques biréfringentes, la microfluidique, l'holographie sélective de polarisation et le stockage de données optique ultrastable ouvrant la porte à l’impression laser de circuits photoniques entièrement intégrés. Cependant, plusieurs verrous technologiques cruciaux empêchent son développement: la création de propriétés optiques non linéaires du second ordre et l'impression d'un pouvoir rotatoire toutes deux avec une orientation correcte en 3D.Outre l'impression bien connue d’une forte biréfringence linéaire et d’un dichroïsme linéaire principalement dues à la formation de nanoréseaux, les résultats de ces travaux de thèse établissent qu'un faisceau laser femtoseconde polarisé linéairement et focalisé dans un verre sous une géométrie axialement symétrique est capable de briser la symétrie chirale. Ici, le matériau (un verre de silice, SiO₂) est achiral, mais l'irradiation laser femtoseconde donne en fait lieu à une propriété optique chirale, c'est-à-dire qu'un pouvoir rotatoire important est signalé pour la première fois. De plus, nous produisons une rotation optique avec un contrôle du signe de la chiralité en contrôlant l'angle entre la polarisation linéaire et la direction de balayage du laser. Un dichroïsme circulaire significatif apparaît également proche de la valeur trouvée pour les molécules organiques. Nous avons suggéré une tentative d'interprétation qui implique l'action d'un couple induit par la lumière sur la matière portant un moment diélectrique induit par la lumière, qui pourrait induire une chiralité moléculaire. Une autre explication est basée sur la biréfringence linéaire interne qui pourrait créer un pouvoir rotatoire au travers d’un assemblage non orthogonal non parallèle de deux (ou plus) contributions linéaires.L’écriture directe par laser femtoseconde offre donc ici un nouvel avantage, en partie de manière non conventionnelle: il permet de restructurer notre matériau optique, pour permettre non seulement l'impression de propriétés anisotropes linéaires mais aussi de propriétés optiques chirales. De façon biomimétique, on peut imaginer produire des dispositifs optiques analogues à cristaux liquides cholestériques en utilisant de minuscules longueurs de verre inorganique c'est-à-dire du verre de silice « twisté ou torsadé». Ces propriétés optiques circulaires pourraient jouer un rôle crucial dans les dispositifs optoélectroniques, la détection biologique et la chimie analytique
Femtosecond Laser Direct Writing (FLDW) allows 3D highly localized permanent modifications of transparent materials with minimal collateral damages. To date, no other manufacturing process has the potential to integrate 3D multifunctional devices made in a single monolithic chip and within a variety of transparent materials. Some aspects of the light-matter interaction are fundamentally new. Solid and plasma coexist for a fraction of picoseconds. In addition, both matter and light interact, resulting to the structuration and shaping of the induced plasma. Here the solid intervenes as a source of electrons. Its microstructure organizes the plasma in coherence with that of the light beam and its vectorial properties (e.g., polarization and its distribution). Then, following the light pulse energy deposition inside the matter, this electron density distribution is "imprinted" by trapping electrons in the solid. A localized stress field can also be stored. The latter can serve as a “source” for the next pulse, thus ensuring a memory effect. In this operation, the solid is restructured by the force field created during the laser irradiation. We can therefore imagine the orientation of the structural modifications like oriented nanostructures (so-called nanogratings), directionally solidified oxide decomposition, oriented nanocrystals or even chiral structures. This is a new physics. But from a chemistry standpoint, there are new aspects to explore as well, since the processes involved are performed in highly excited states, and largely off equilibrium. It is therefore necessary to question some previous ideas for understanding matter excitation and relaxation, and then to control the laser-induced structure and properties. Recently, these properties were successfully harnessed for multiple practical applications, including polarization optics, microfluidics, polarization selective holography and ultra-stable optical data storage opening the door towards all-integrated photonics circuits. However, several technological critical limitations prevent further developments among which 1) the creation of second order non-linear optical properties and 2) imprinting some optical rotation, both with tunable orientation in 3D.Apart the well-known imprinting of linear birefringence and dichroism mostly due to the formation of nanogratings, the results establish that a linearly polarized femtosecond laser beam focused inside a glass, and under an axially symmetric geometry, is able to break the chiral symmetry of the material. Here, the material is a silica glass and therefore achiral, but femtosecond laser irradiation actually gives rise to a chiral optical property, i.e., a significant optical rotation. This is reported for the first time. Additionally, we were able to induce optical rotation and to control the chiral sign by tuning the angle between the linear polarization direction and the scanning direction. A significant circular di-attenuation also appears that is close to the value found for organic molecules. We suggested a tentative interpretation that involves the action of a light-induced torque on the matter carrying a light-induced dielectric moment that could induce molecular optical activity. Another suggested explanation is based on internal linear birefringence that could be related to a non-parallel and non-orthogonal assembly of two (or more) linear contributions.Thus, in this context FLDW offers a new advantage, partly in a non-conventional way: it allows restructuring of our most important optical materials, to enable the imprinting of anisotropic linear optical properties but also chiral optical properties. In a biomimetic way, we can envision the fabrication of cholesteric liquid crystal analogous optical devices using tiny lengths of inorganic glass i.e. “twisted silica glass”. Such circular optical properties could play a determining role in optoelectronic devices, biological sensing, and analytical chemistry
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Kang, Seungyeon. "Femtosecond laser direct writing of 3D metallic structures and 2D graphite." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11495.

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This thesis explores a novel methodology to fabricate three dimensional (3D) metal-dielectric structures, and two dimensional (2D) graphite layers for emerging metamaterials and graphene applications. The investigations we report here go beyond the limitations of conventional fabrication techniques that require multiple post-processing steps and/or are restricted to fabrication in two dimensions. Our method combines photoreduction mechanism with an ultrafast laser direct writing process in innovative ways. This study aims to open the doors to new ways of manufacturing nanoelectronic and nanophotonic devices. With an introductory analysis on how the various laser and chemical components affect the fabrication mechanism, this dissertation is divided into three sections.
Engineering and Applied Sciences
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Vora, Kevin Lalitchandra. "Three-dimensional nanofabrication of silver structures in polymer with direct laser writing." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11335.

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This dissertation describes methodology that significantly improves the state of femtosecond laser writing of metals. The developments address two major shortcomings: poor material quality, and limited 3D patterning capabilities. In two dimensions, we grow monocrystalline silver prisms through femtosecond laser irradiation. We thus demonstrate the ability to create high quality material (with limited number of domains), unlike published reports of 2D structures composed of nanoparticle aggregates. This development has broader implications beyond metal writing, as it demonstrates a one-step fabrication process to localize bottom-up growth of high quality monocrystalline material on a substrate. In three dimensions, we direct laser write fully disconnected 3D silver structures in a polymer matrix. Since the silver structures are embedded in a stable matrix, they are not required to be self-supported, enabling the one-step fabrication of 3D patterns of 3D metal structures that need-not be connected. We demonstrate sub-100-nm silver structures. This latter development addresses a broader limitation in fabrication technologies, where 3D patterning of metal structures is difficult. We demonstrate several 3D silver patterns that cannot be obtained through any other fabrication technique known to us. We expect these advances to contribute to the development of new devices in optics, plasmonics, and metamaterials. With further improvements in the fabrication methods, the list of potential applications broadens to include electronics (e.g. 3D microelectronic circuits), chemistry (e.g. catalysis), and biology (e.g. plasmonic biosensing).
Engineering and Applied Sciences
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Moebius, Michael. "Applications of Nonlinear Optics in 3D Direct Laser Writing and Integrated Nanophotonics." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493316.

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This thesis presents novel applications of nonlinear optics in laser fabrication and sources of entangled photons for quantum optics. Femtosecond direct laser writing in transparent media enables mask-less fabrication of sub-micrometer scale features with flexibility in feature shape and position in the x, y, and z-directions. Different applications in optics can be enabled by working in a variety of material platforms. We explore direct laser writing of metal structures in polymer matrices for applications in diffraction optics and modification of hydrogenated amorphous silicon (a-Si:H) for integrated optical devices. These topics explore how nonlinear optical interactions are applied to alter material properties using light. Conversely, nonlinear interactions can be used for wavelength conversion. Nonlinear interactions in nanoscale waveguides can be leveraged to produce efficient sources of entangled photons for applications in quantum optics. We explore using a novel photonic platform, titanium dioxide (TiO2), to realize third-order spontaneous parametric down-conversion (TOSPDC) for direct generation of entangled photon triplets. There is a need for new fabrication techniques that enable true 3D fabrication on the sub-micrometer scale. Diffraction optical elements have many potential applications in imaging, wavelength selection, and dispersion compensation. Multi-layer diffraction optical elements could be used to integrate imaging systems on-chip for lab-on-chip devices, such as microfluidic systems. We explore using 3D laser-written metal structures in polymer matrices for 3D gratings and diffractive elements, such as zone plates and pinholes. We demonstrate diffraction from 3D gratings and imaging using zone plates. 3D fabrication of waveguides has enabled fabrication of complex optical systems within optical fibers and bulk glasses. We explore using femtosecond laser interactions with hydrogenated amorphous silicon to introduce refractive index changes. a-Si:H could be directly integrated with CMOS devices and has the potential for much higher index contrast than bulk glasses, enabling dense, multi-layer optical devices. Efficient sources of three or more entangled photons are necessary for advances in quantum photonics. Current techniques are highly limited because they rely on cascaded second order down-conversion processes to produce entangled photon triplets and often are based in bulk optics. We leverage the high transparency, high linear refractive index, and high chi(3) nonlinearity in TiO2 to develop integrated, on-chip nano-scale waveguide sources of entangled photon triplets via TOSPDC. We present the phase-matching and nonlinear overlap conditions necessary and explore important experimental design considerations.
Engineering and Applied Sciences - Applied Physics
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Books on the topic "DIRECT LASER WRITING LITHOGRAPHY"

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Wei, Xiaoli. Vacuum-ultraviolet laser direct writing of buried waveguides in fused silica bulk glass. Ottawa: National Library of Canada, 2002.

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Cheng, Ya. Microbiochips monolithically integrated with microfluidics, micromechanics, photonics, and electronics by 3D femtosecond laser direct writing. Hauppauge, N.Y: Nova Science Publishers, 2010.

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Kang, Seungyeon. Femtosecond laser direct writing of 3D metallic structures and 2D graphite. 2014.

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Vora, Kevin Lalitchandra. Three-dimensional nanofabrication of silver structures in polymer with direct laser writing. 2014.

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Wong, Sean Hang Edmond. Fabrication of three-dimensional photonic crystals via direct laser writing in an all-inorganic photoresist. 2005.

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Wong, Sean Hang Edmond. Fabrication of three-dimensional photonic crystals via direct laser writing in an all-inorganic photoresist. 2005.

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Wong, Sean Hang Edmond. Fabrication of three-dimensional photonic crystals via direct laser writing in an all-inorganic photoresist. 2005, 2005.

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Shoji, Satoru, Remo Proietti Zaccaria, and Satoshi Kawata. Holographic laser processing for three-dimensional photonic lattices. Edited by A. V. Narlikar and Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533053.013.9.

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This article describes a holographic laser-processing method for independently controlling the lattice symmetry and lattice constant in three-dimensional photonic lattices. With this approach, optical periodicity is created in lower dimensions and three-dimensional periodicity is obtained by a combination of several lower-dimensional periodic structures. The proposed holographic laser-processing method is compared with the standard four-beam technique. Examples of experimental demonstration achieved in photosensitive polymers are given. The article also introduces a multiphoton direct-writing technique for creating defect structures in lattices towards production of defect cavity-functionalized photonic crystal devices. It shows that all Bravais lattices can be produced by choosing proper incident vectors of laser beams. The lattice constant of the structure can be changed without distorting its lattice symmetry and lattice elements.
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Book chapters on the topic "DIRECT LASER WRITING LITHOGRAPHY"

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Gierak, Jacques. "Focused Ion Beam Direct-Writing." In Lithography, 183–232. Hoboken, NJ USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118557662.ch4.

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Bäuerle, Dieter. "Direct Writing." In Laser Processing and Chemistry, 407–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-17613-5_18.

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Bäuerle, Dieter. "Direct Writing." In Laser Processing and Chemistry, 317–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/978-3-662-03253-4_18.

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Engelhardt, Sascha. "Direct Laser Writing." In Laser Technology in Biomimetics, 13–65. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-41341-4_2.

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Terakawa, Mitsuhiro. "Femtosecond Laser Direct Writing." In Toxinology, 1–19. Dordrecht: Springer Netherlands, 2018. http://dx.doi.org/10.1007/978-981-10-6588-0_14-1.

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Terakawa, Mitsuhiro. "Femtosecond Laser Direct Writing." In Toxinology, 1–19. Dordrecht: Springer Netherlands, 2018. http://dx.doi.org/10.1007/978-981-10-6588-0_14-2.

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Terakawa, Mitsuhiro. "Femtosecond Laser Direct Writing." In Micro/Nano Technologies, 481–98. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-0098-1_14.

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Bloomstein, T. M., S. T. Palmacci, R. H. Mathews, N. Nassuphis, and D. J. Ehrlich. "Advances in Laser Direct Writing." In Laser Processing: Surface Treatment and Film Deposition, 895–906. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0197-1_49.

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Garrido, C., D. Braichotte, H. van den Bergh, B. León, and M. Pérez-Amor. "Laser Direct Writing of Platinum Lines." In Laser/Optoelektronik in der Technik / Laser/Optoelectronics in Engineering, 705–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-48372-1_150.

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Auvert, G., Y. Pauleau, and D. Tonneau. "Laser Direct Writing for Device Applications." In Emerging Technologies for In Situ Processing, 201–11. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1409-4_21.

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Conference papers on the topic "DIRECT LASER WRITING LITHOGRAPHY"

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Ostendorf, Andreas, Juergen Koch, Frank Meyer, and Boris N. Chichkov. "Lithography by maskless laser direct writing." In PICALO 2006: 2nd Pacific International Conference on Laser Materials Processing, Micro, Nano and Ultrafast Fabrication. Laser Institute of America, 2006. http://dx.doi.org/10.2351/1.5056927.

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Jung, Howon, Yongwoo Kim, Seok Kim, Jinhee Jang, and Jae W. Hahn. "High-resolution laser direct writing with a plasmonic contact probe." In SPIE Advanced Lithography, edited by William M. Tong. SPIE, 2012. http://dx.doi.org/10.1117/12.916359.

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Yang, GuoGuang, and Yibing Shen. "Laser direct writing system and its lithography properties." In Photonics China '98, edited by ShuShen Deng and S. C. Wang. SPIE, 1998. http://dx.doi.org/10.1117/12.317917.

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Guo, Yongkang, Jinglei Du, Qizhong Huang, Jun Yao, Chuankai Qiu, and Zheng Cui. "Optical proximity correction for submicron lithography by laser direct writing." In Microlithography '99, edited by Luc Van den Hove. SPIE, 1999. http://dx.doi.org/10.1117/12.354383.

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Ghosh, Siddharth, and G. K. Ananthasuresh. "A Note on High Aspect-Ratio SU-8 Micromechanical Structures Using Mask-Less Direct Laser Writing." In ASME 2012 International Manufacturing Science and Engineering Conference collocated with the 40th North American Manufacturing Research Conference and in participation with the International Conference on Tribology Materials and Processing. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/msec2012-7413.

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We report high aspect-ratio micromechanical structures made of SU-8 polymer, which is a negative photoresist. Mask-less direct writing with 405 nm laser is used to pattern spin-cast SU-8 films of thickness of more than 600 um. As compared with X-ray lithography, which helps pattern material to give aspect ratios of 1:50 or higher, laser writing is a less expensive and more accessible alternative. In this work, aspect ratios up to 1:30 were obtained on narrow pillars and cantilever structures. Deep vertical patterning was achieved in multiple exposures of the surface with varying dosages given at periodic intervals of sufficient duration. It was found that a time lag between successive exposures at the same location helps the material recover from the transient changes that occur during exposure to the laser. This gives vertical sidewalls to the resulting structures. The time-lags and dosages were determined by conducting several trials. The micromechanical structures obtained with laser writing are compared with those obtained with traditional UV lithography as well as e-beam lithography. Laser writing gives not only high aspect ratios but also narrow gaps whereas e-beam can only give narrow gaps over very small depths. Unlike traditional UV lithography, laser writing does not need a mask. Furthermore, there is no adjustment for varying the dosage in traditional UV lithography. A drawback of this method compared to UV lithography is that the writing time increases. Some test structures as well as a compliant microgripper are fabricated.
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Ai, Jun, Jianguo Liu, Qifeng Du, Ming Lv, and Xiaoyan Zeng. "Laser direct writing lithography for rapid fabrication on non-planar surfaces." In ICALEO® 2017: 36th International Congress on Applications of Lasers & Electro-Optics. Laser Institute of America, 2017. http://dx.doi.org/10.2351/1.5138182.

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Kohut, Tomáš, Jakub Toběrný, and Kamil Postava. "Optimization of exposure parameters for direct laser writing in optical lithography." In 22nd Polish-Slovak-Czech Optical Conference on Wave and Quantum Aspects of Contemporary Optics, edited by Waclaw Urbańczyk and Jan Masajada. SPIE, 2022. http://dx.doi.org/10.1117/12.2664190.

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Shen, Chuan, ShiQi Lv, JiaQi Fang, JiaLi Sun, YiFei Qi, and Sui Wei. "Color computational holographic display based on laser direct writing lithography technology." In Conference on Display Technology and Optical Storage, edited by Yongtian Wang. SPIE, 2021. http://dx.doi.org/10.1117/12.2606842.

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Rumler, M., M. Kollmuss, L. Baier, F. Michel, M. Förthner, M. Becker, M. Rommel, and L. Frey. "Combination of direct laser writing and soft lithography molds for combined nano- and microfabrication." In 32nd European Mask and Lithography Conference, edited by Uwe F. W. Behringer and Jo Finders. SPIE, 2016. http://dx.doi.org/10.1117/12.2248219.

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Malinauskas, Mangirdas, Albertas Žukauskas, and Kastytis Belazaras. "Employment of fluorescence for autofocusing in direct laser writing micro-/nano-lithography." In SPIE Optical Engineering + Applications, edited by R. Barry Johnson, Virendra N. Mahajan, and Simon Thibault. SPIE, 2014. http://dx.doi.org/10.1117/12.2061261.

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Reports on the topic "DIRECT LASER WRITING LITHOGRAPHY"

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Smith, Henry I. Direct Writing of X-ray Gratings Using Zone-Plate-Array Lithography (ZPAL). Office of Scientific and Technical Information (OSTI), February 2017. http://dx.doi.org/10.2172/1344384.

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Farsari, Maria. Three Dimensional Optical Metamaterials via Direct Laser Writing. Fort Belvoir, VA: Defense Technical Information Center, March 2013. http://dx.doi.org/10.21236/ada582506.

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Guney, Durdu O., Thomas Koschny, Maria Kafesaki, and Costas M. Soukoulis. Bulk Negative Index Photonic Metamaterials for Direct Laser Writing. Fort Belvoir, VA: Defense Technical Information Center, January 2008. http://dx.doi.org/10.21236/ada524062.

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