Ultrashort pulse laser systems enable new approaches of material processing and manufacturing with enhanced precision and productivity. Time- and cost-effectiveness in the context of the industrialization of ultrashort laser pulse processes require an improvement of processing speed, which is of key importance for strengthening industrial photonics based manufacturing and extending its field of applications. This article presents results on improving the speed of a laser process by parallelization for creating light deflecting volume optics. Diffractive optical elements are fabricated directly inside the encapsulant of solar modules by utilizing a spatial light modulator based parallel laser microfabrication method. The fabricated volume optical elements effectively deflect light away from front side electrodes and significantly reduce the corresponding optical losses.

Nanostructured composites of inorganic and organic materials are attracting extensive interest for electronic and optoelectronic device applications. Here we report a novel method for the fabrication and patterning of metal selenide nanoparticles in organic semiconductor films that is compatible with solution processable large area device manufacturing. Our approach is based upon the controlled in situ decomposition of a cadmium selenide precursor complex in a film of the electron transporting material 1,3,5-tris(N-phenyl-benzimidazol-2-yl)-benzene (TPBI) by thermal and optical methods. In particular, we show that the photoluminescence quantum yield (PLQY) of the thermally converted CdSe quantum dots (QDs) in the TPBI film is up to 15%. We also show that laser illumination can form the QDs from the precursor. This is an important result as it enables direct laser patterning (DLP) of the QDs. DLP was performed on these nanocomposites using a picosecond laser. Confocal microscopy shows the formation of emissive QDs after laser irradiation. The optical and structural properties of the QDs were also analysed by means of UV-Vis, PL spectroscopy and transmission electron microscopy (TEM). The results show that the QDs are well distributed across the film and their emission can be tuned over a wide range by varying the temperature or irradiated laser power on the blend films. Our findings provide a route to the low cost patterning of hybrid electroluminescent devices.

Metal nanowires sustain propagating surface plasmons that are strongly confined to the wire surface. Plasmon reflection at the wire end faces and interference lead to standing plasmon modes. We demonstrate that these modes can be imaged via two-photon (plasmon) polymerization of a thin film resist covering the wires and subsequent electron microscopy. Thereby, the plasmon wavelength and the phase shift of the nanowire mode picked up upon reflection can be directly retrieved. In general terms, polymerization imaging is a promising tool for the imaging of propagating plasmon modes from the nano- to micro-scale.

In many areas of science and technology, patterned films and surfaces play a key role in engineering and development of advanced materials. Here, we present a versatile toolbox that provides an easy patterning method for cellulose thin films by means of photolithography and enzymatic digestion. A patterned UV-illumination of trimethylsilyl cellulose thin films containing small amounts of a photo acid generator leads to a desilylation reaction and thus to the formation of cellulose in the irradiated areas. Depending on the conditions of development, either negative and positive type cellulose structures can be obtained, offering lateral resolutions down to the single-digit micro meter range by means of contact photolithography. In order to highlight the potential of this material for advanced patterning techniques, cellulose structures with sub-µm resolution are fabricated by means of two-photon absorption lithography. Moreover, these photochemically structured cellulose thin films are successfully implemented as dielectric layers in prototype organic thin film transistors. Such photopatternable dielectric layers are crucial for the realization of electrical interconnects for demanding organic device architectures.

Berliner Glas is a privately owned, mid-sized manufacturer of precision opto-mechanics in Germany. One specialty of Berliner Glas is the design and production of high performance vacuum and electrostatic wafer chucks. Driven by the need of lithography and inspection for smaller overlay values, we pursue the production of an ideally flat wafer chuck. An ideally flat wafer chuck holds a wafer with a completely flat backside and without lateral distortion within the wafer surface. Key parameters in influencing the wafer chucks effective flatness are thermal performance and thermal management, roughness of the surface, choice of materials and the contact area between wafer and wafer chuck. In this presentation we would like to focus on the contact area. Usually this is decreased as much as possible to avoid sticking effects and the chance of trapped particles between the chuck surface and the backside of the wafer. This can be realized with a pin structure on the chuck surface. Making the pins smaller and moving pins further apart from each other makes the contact area ever smaller but also adds new challenges to achieve a flat and undistorted wafer on the chuck. We would like to address methods of designing and evaluating such a pin structure. This involves not only the capability to simulate the ideal pattern of pins on the chuck’s surface, for which we will present 2D and 3D simulation results. As well, we would like to share first results of our functional models. Finally, measurement capability has to be ensured, which means improving and further development of Fizeau flatness test interferometers.

Optical waveguides are becoming increasingly important in the developing area of broadband communications. The field of electronics is advancing rapidly, leading to further demands for larger data storage, smaller components and a better design of integrated optical circuits. The integration of optical interconnects on printed circuit boards (PCBs) requires precise technologies to make this emerging field possible. A promising new microfabrication technique, two-photon photopolymerisation (2PP) can be used to produce three dimensional structures in the sub-micron region. Near-infrared lasers can be used to create 3D optical waveguides by initiating the photopolymerisation of high refractive index monomers in polymeric matrix materials. Terminal silanol groups are intermediates for room temperature vulcaniseable (RTV) silicones and can be cross linked with functional silanes to produce flexible, transparent polymeric materials with high thermal stabilities. A silanol terminated polysiloxane; cross linked with a methyl substituted acryloxy silane has been developed as a suitable material for the fabrication of optical waveguides by two-photon absorption (TPA). A higher refractive index is achieved upon polymerisation of the acrylate functional groups. The material has been shown to be suitable in the fabrication of 3D optical waveguides with a high refractive index contrast. The cured material is fully flexible and exhibits high thermal stability and optical transparency. The material was characterised by Fourier transform infrared spectroscopy (FT-IR), simultaneous thermal analysis coupled with mass spectrometry (STA-MS) and near-infrared spectroscopy (NIRS). Waveguides were observed by phase contrast microscopy, cut back measurements and were additionally directly integrated onto specially designed PCBs by correctly positioning waveguide bundles between optoelectronic components using TPA.

Optimizing the properties of optical and photonic devices calls for the need to control and manipulate light within structures of different length scales, ranging from sub-wavelength to macroscopic dimensions. Working at different length scales, however, requires different simulation approaches, which have to account properly for various effects such as polarization, interference, or diffraction: at dimensions much larger than the wavelength of light common ray-tracing techniques are conveniently employed, while in the (sub-)wavelength regime more sophisticated approaches, like the socalled finite-difference time-domain (FDTD) technique, are used. Describing light propagation both in the (sub-)wavelength regime as well as on macroscopic length scales can only be achieved by bridging between these two approaches. Unfortunately, there are no well-defined criteria for a switching from one method to the other, and the development of appropriate selection criteria is a major issue to avoid a summation of errors. Moreover, since the output parameters of one simulation method provide the input parameters for the other one, they have to be chosen carefully to ensure mathematical and physical consistency. In this contribution we present an approach to combine classical ray-tracing with FDTD simulations. This enables a joint simulation of both, the macro- and the microscale which refer either to the incoherent or the coherent effects, respectively. By means of an example containing one diffractive optical element (DOE) and macroscopic elements we will show the basic principles of this approach and the simulation criteria. In order to prove the physical correctness of our simulation approach, the simulation results will be compared with real measurements of the simulated device. In addition, we will discuss the creation of models in FDTD based on different analyze techniques to determine the dimensions of the DOE, as well as the impact of deviations between these different FDTD models on the simulation results.

Ring opening metathesis polymerization (ROMP) has become an important tool for the synthesis of highly defined polymers and various polymer architectures. In the present work, the residual double bonds in ROMP derived polymeric materials were exploited for a photoinduced thiol–ene reaction in order to achieve a selective cross-linking of the macromolecules. Besides the photoinduced thiol–ene reaction, which was investigated by means of FT-IR measurements, also the resulting change in the refractive index was studied by spectroscopic ellipsometry. To demonstrate the versatility of this reaction for the realization of 3D polymeric microstructures, films of poly(norbornene dicarboxylic acid, dimethylester) were structured via two-photon induced cross-linking. The accessibility and reactivity of the polynorbornene main chain CC double bonds in the thiol–ene reaction pave the way towards novel strategies for the realization of polymer 3D microstructures.

In this contribution we describe a microfluidic chip combining plasma separation, sample metering, dissolution/incubation with reagents stored on-chip and optical detection. The system allows defining the incubation time and works under constant externally applied pressure using only passive valves for actuation. This allowed the realization of a bioanalytical device for whole blood samples comprising a disposable plastic chip using TIRF (total internal reflection fluorescence) based optical detection of biochemical binding events.

This chapter introduces the scope of the book. It is intended to guide the reader through the book, to find specific information by shortly summarizing information from the following chapters and to build a cross reference to the various applied methods and the corresponding applications. The laser as a powerful light source can be found in nearly any technical application, ranging from consumer electronics (CD, DVD, blu-ray player, scanner), metrology (including environmental monitoring), scientific research (laser development to novel fields in quantum physics, photonics and medicine), arts, industry, information technology to lithography and material processing. It is obvious that the laser meets many requirements from technical challenges inspired by natural evolutionary solutions. Not all of them can be treated in a single book, but a cross section of the powerful combination of both, laser technology and biomimetic thinking, form a powerful approach to novel technical application scenarios as presented in the next chapters, which are considered as guideline and orientation for the reader depending on a laser or application based approach.

The lately in literature described use of two photon based photo processes for producing optical interconnections arises the need of suitable optical functional materials. The present work concerns the development, investigation and processing of a flexible siloxane based organic-inorganic hybrid (OIH) material for the fabrication of optical waveguides for data transmission on printed circuit boards (PCBs). In the developed system the waveguide core is formed by two photon induced photopolymerization (TPIP) of selected monomers, which are dissolved in a polysiloxane matrix. Through the photo induced polymerization an interpenetrating network is generated, resulting in a refractive index change between the non-illuminated waveguide cladding and the illuminated core material. Due to the optical transparency, flexibility and chemical and thermal stability, polysiloxanes were chosen as optical matrix material. Different types of methacrylates with a high refractive index were used as monomers.In order to obtain a high contrast in refractive index, the monomers were removed from non-illuminated regions in a vacuum process after laser exposure. The written optical waveguides were evidenced by phase contrast microscopy, revealing an excellent structuring behavior of the developed material. Optical techniques e.g. cut-back measurements and light extraction tests were applied to characterize the inscribed waveguide structures and to detect the resulting optical loss. Conversion rate of the monomers, which occurred through structuring, was verified by FTIR. To determine the refractive index change upon UV irradiation spectroscopic ellipsometry was applied. As a result of the polymerization, a difference of Delta n = 0.02 between the non-illuminated cladding and the illuminated core material was detected. Additionally, prototypes of optical interconnects on PCBs were fabricated by inscription of a waveguide bundle between a mounted laser and photo diode, resulting in the desired increase of the transmitted photocurrent after TPA structuring. In conclusion, the obtained results demonstrate that fully flexible optical interconnects are accessible by the developed process. (C) 2011 Elsevier B.V. All rights reserved.

The brilliancy and variety of structural colors found in nature has become a major scientific topic in recent years. Rapid-prototyping processes enable the fabrication of according structures, but the technical exploitation requires a profound understanding of structural features and material properties regarding the generation of reflected color. This paper presents an extensive simulation of the reflectance spectra of a simplified 2D Morpho butterfly wing model by utilizing the finite-difference time-domain method. The structural parameters are optimized for reflection in a given spectral range. A comparison to simpler models, such as a plane dielectric layer stack, provides an understanding of the origin of the reflection behavior. We find that the wavelength of the reflection maximum is mainly set by the lateral dimensions of the structures. Furthermore small variations of the vertical dimensions leave the spectral position of the reflectance wavelength unchanged, potentially reducing grating effects.

3D polymeric optical waveguides play an intrinsic role in a rapidly developing area of broadband communications. Advances in the field of electronics means there is a greater demand for higher speeds, larger data storage, smaller components and the improvement in the design of integrated optical circuits. Two-photon photopolymerisation (2PP) is a promising three-dimensional microfabrication technique, which can be used to produce structures in the sub-micron region. With the use of near-infrared (NIR) lasers, 3D optical waveguides can be fabricated in polymer-based matrix materials, based on the increase of the refractive index in the vicinity of the laser focus.The development of a new polysiloxane material, used in the study of the integration of optical interconnects on printed circuit boards is presented. The desirable properties of epoxy functional silicones crosslinked with diamines deem them suitable for such applications. An epoxy terminated polysiloxane: crosslinked with an aminopropyl disiloxane has been developed as a suitable material for the fabrication of optical waveguides by two-photon absorption (TPA). The material fulfils a number of requirements including a good refractive index contrast between the matrix material and inscribed waveguide, full flexibility and high thermal stability.The matrix material was characterised by Fourier transform infrared spectroscopy (FUR) and thermal gravimetric analysis (TGA) The optical waveguides were characterised by phase contrast microscopy, and were directly integrated onto specially designed PCB's by correctly positioning waveguide bundles between optoelectronic components using TPA, making it possible to detect transmitted photocurrents. (C) 2011 Elsevier Ltd. All rights reserved.

The increasing demand for miniaturization and design flexibility of polymer optical waveguides integrated into electrical printed circuit boards (PCB) calls for new coupling and integration concepts.We report on a method that allows the coupling of optical waveguides to electro-optical components as well as the integration of an entire optical link into the PCB. The electro-optical devices such as lasers and photodiodes are assembled on the PCB and then embedded in an optically transparent material. A focused femtosecond laser beam stimulates a polymerization reaction based on a two-photon absorption effect in the optical material and locally increases the refractive index of the material. In this way waveguide cores can be realized and the embedded components can be connected optically. This approach does not only allow a precise alignment of the waveguide end faces to the components but also offers a truly 3-dimensional routing capability of the waveguides.Using this technology we were able to realize butt-coupling and mirror-coupling interface solutions in several demonstrators. We were also manufacturing demonstrator boards with fully integrated driver and preamplifier chips, which show very low power consumption of down to 10 mW for about 2.5 Gbit/s. Furthermore, demonstrators with interconnects at two different optical layers were realized.

The performance of an optical sensor device working on the basis of integrated waveguides relies on the efficient coupling of light into and out of the waveguide. Conventional coupling methods are based on the usage of optical components such as prisms or gratings. An alternative approach utilizes fluorescent molecules inside the core material of the waveguide, and thereby avoids complex and time consuming alignment procedures. In that context the application of fluorescence resonance energy transfer (FRET) enables the effective separation of excitation and emission light due to a large effective Stokes shift and accordingly small re-absorption of the dye molecules. Within the framework of the presented work, fluorescent molecules are used to couple light into a PDMS/polystyrene waveguide system. The dye molecules are optically characterized and embedded into the waveguide system. It is demonstrated that the position of the molecules relative to the waveguide influences the amount of light coupled into the system. The efficient coupling of light out of the waveguide is important to guide the light to a detecting device for directly measuring the optical throughput through the system. Two basic out coupling principles have been applied, end-face coupling and out coupling at scattering layers. The system has also been examined by means of ray tracing simulations, which reveal the influence of various system parameters such as the position of the dye molecules in the waveguide core and optical properties of the materials.

This paper reports how waveguides can be structured directly into a matrix made out of Poly(dimethyl siloxane) (PDMS) using 2PP.To fulfill the economical aspects of a fabrication of optical interconnects, a cost effective, mechanically flexible and temperature-resistant matrix material with a low attenuation in optical applications (smaller than 0.1 dB/cm at 850 nm wavelength) such as PDMS is needed.

The three‐dimensional fabrication of optical waveguides has gained increasing interest in recent years to establish interconnections between electrical components on a very small scale where copper circuits encounter severe limitations. In this work the application of optically clear, organically modified porous silica monoliths and thin films as a host material for polymeric waveguides to be inscribed into the solid host structure by two‐photon‐induced photopolymerization is investigated. Porosity is generated using a lyotropic liquid crystalline surfactant/solvent system as a template for the solid silica material obtained by a sol–gel transition of a liquid precursor. In order to reduce the brittleness of the purely inorganic material, organic–inorganic co‐precursor molecules that contain poly(ethylene glycol) chains are synthesized and added to the mixture, which successfully suppresses macroscopic cracking and leads to flexible thin films. The structure of the thus‐obtained porous organic–inorganic hybrid material is investigated by atomic force microscopy. It is shown that the modified material is suitable for infiltration with photocurable monomers and functional polymeric waveguides can be inscribed by selective two‐photon‐induced photopolymerization.