Linearly modulated multi-focal diffractive lens for multi-sheet excitation of flow driven samples in a light-sheet fluorescence microscope. - In: Journal of the European Optical Society, ISSN 1990-2573, Bd. 19 (2023), 1, 26, S. 1-8
Light sheet fluorescence microscope with single light sheet illumination enables rapid 3D imaging of living cells. In this paper we show the design, fabrication and characterization of a diffractive optical element producing several light sheets along a 45˚ inclined tube. The element, which is based on a multi-focal diffractive lens and a linear grating, generates five thin light sheets with equal intensities when combined with a refractive cylindrical lens. The generated uniform light sheets can be applied for the scanning of samples in tubes enabling flow-driven 3-dimensional imaging.
Mikrostrukturierte Spezialgläser für mikromechanische und mikrooptische Anwendungen. - In: Mikrosystemtechnik, (2022), S. 35-38
2.5D etching of silicon dioxide for optical and photonic structures. - In: 2022 IEEE Photonics Conference (IPC), (2022), insges. 2 S.
We investigated the ability to control the sidewall-angle for the etching of SiO2 by tuning process parameters. We found a strong correlation between sidewall-angle and temperature, enabling control of the sidewall-angle from 60˚-90˚, and found a curved etch profile which was named quasi-isotropic.
Manufacturing of nanostructures in silicon carbide using UV-nanoimprint lithography in combination with fluorine-based plasma etching. - In: 2022 IEEE Photonics Conference (IPC), (2022), insges. 2 S.
The combination of a multi-layer resist system for soft UV-NIL with a fluorine-based plasma etching is investigated to elaborate homogeneously distributed nanosized features in silicon carbide. Initial studies substantiate that this approach can be a timesaving and cost-effective alternative to generate nanostructures in SiC.
Simulation model and dimensioning of a photoacoustic sensor for the detection of radiation-induced pressure surges. - In: MikroSystemTechnik, (2021), S. 523-526
Whispering Gallery Resonators with diffractive coupling elements. - In: MikroSystemTechnik, (2021), S. 230-233
Vergleich zur Plasmastrukturierbarkeit von Materialien mit sehr geringer thermischer Ausdehnung. - In: MikroSystemTechnik, (2021), S. 51-54
Efficient and cost-effective manufacturing of nanostructures with high aspect ratios using Soft UV-Nanoimprint Lithography with bi- and trilayer resist systems. - In: MikroSystemTechnik, (2021), S. 35-38
Traceable 5D-nanofabrication with nano positioning and nano measuring machines. - In: Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, (2021), S. 333-336
Today, besides the ongoing progress in the reduction of feature sizes, the measuring and fabrication of freeform surfaces with nanometre uncertainty, e.g. for aspheric lenses or structures with high aspect ratios, are a challenging task. Usually, dealing with such objects is limited by the local tilt angle between the object surface and the tool axis. There are different approaches to perform such measurements. In this paper, an extension of the Nano Measuring Machine NMM-1 with two rotational axes is described. With the proposed setup, it is possible to orientate the tool-axis perpendicular to the sample in every position, allowing larger angles to be measured / structured and minimising the uncertainty of the process e.g. due to the tilt dependency of the tool. Various machine designs are investigated and finally a solution with one rotary and one goniometer stage is integrated, preserving the existing machine infrastructure and allowing the addressability of a full hemisphere without limiting the measuring volume. As the tool centre point maintains its position during tool rotation, the Abbe principle is still fulfilled in every angular orientation. Emphasis was put on the metrological traceability of the whole system, including linear and rotary axes as well the tool itself. This was achieved by using a reference hemisphere, compensating the trajectory errors of the rotational axes. For the developed arrangement, the measurement uncertainty was investigated and several strategies for an in-situ-calibration of the additional axes are described. Finally, nanofabrication on large slopes is demonstrated.
Nano-imprinted subwavelength gratings as polarizing beamsplitters. - In: Journal of the European Optical Society, ISSN 1990-2573, Bd. 17 (2021), 1, 4, S. 1-13
Polarizing beamsplitters have numerous applications in optical systems, such as systems for freeform surface metrology. They are classically manufactured from birefringent materials or with stacks of dielectric coatings. We present a binary subwavelength-structured form-birefringent diffraction grating, which acts as a polarizing beamsplitter for a wide range of incidence angles -30˚…+30˚. We refine the general design method for such hybrid gratings. We furthermore demonstrate the manufacturing steps with Soft-UV-Nanoimprint-Lithography, as well as the experimental verification, that the structure reliably acts as a polarizing beamsplitter. The experimental results show a contrast in efficiency for TE- and TM-polarization of up to 1:18 in the first order, and 34:1 in the zeroth order. The grating potentially enables us to realize integrated compact optical measurement systems, such as common-path interferometers.