Konferenzschriften

Lin, Shan; Rothleitner, Christian; Rogge, Norbert
Amplitude estimation using three-parameter sine fitting algorithm in the Planck-Balance. - In: Electrical and electronic measurements promote industry 4.0, (2020), S. 77-80

Belkner, Johannes; Hofmann, Martin; Kirchner, Johannes; Manske, Eberhard
Demonstration of aberration-robust high-frequency modulated Differential Confocal Microscopy with an oscillating Pinhole. - In: Optics and Photonics for Advanced Dimensional Metrology, (2020), S. 113520N-1-113520N-10

Metrological stages such as the nano-positioning and nano-measurement machine (NPMM) can position single-digit nanometer accurately on centimeter working volumes. However, their measurement system requires a feedback to the arbitrary shaped specimen by another probe. The differential confocal microscopy (DCM) offers the possibility to have a sensitivity down to that single-digit nanometers but suffers from noise and aberration. Recently the principle of the LockIn filtering could be successfully adapted in DCM and therefore achieved a high SNR. Contrary to the there employed acoustically driven tunable GRIN lens (TAG lens) at the objective, we demonstrate a microelectromechanical system (MEMS), an AFM cantilever, as an ultrafast oscillating pinhole in front of the detector. Its first resonance at 96kHz makes it very competitive regarding acquisition speed, but the low oscillation amplitude lowers contrast. By principle inheriting the possibility to compensate a change in reflectivity, we present another advancement for the evaluation of the resulting differential signal to make it robust against sample induced systematic depth errors, e.g. a tilt-angle. This could be advantageous for DCM with static beam-paths, as well. Potentially, the highest improvement can be achieved in conjunction with the NPMMs highly accurate measurement interferometers, because the residual error for the depth of a specimen under the influence of varying aberration is kept below 20nm.

https://doi.org/10.1117/12.2555558

Ortlepp, Ingo; Kühnel, Michael; Hofmann, Martin; Mohr-Weidenfeller, Laura; Kirchner, Johannes; Supreeti, Shraddha; Mastylo, Rostyslav; Holz, Mathias; Michels, Thomas; Füßl, Roland; Rangelow, Ivo W.; Fröhlich, Thomas; Dontsov, Denis; Schäffel, Christoph; Manske, Eberhard
Tip- and laser-based nanofabrication up to 100 mm with sub-nanometre precision. - In: Novel Patterning Technologies for Semiconductors, MEMS/NEMS and MOEMS 2020, (2020), S. 113240A-1-113240A-17

Although the field of optical lithography is highly investigated and numerous improvements are made, structure sizes smaller than 20 nm can only be achieved by considerable effort when using conventional technology. To cover the upcoming tasks in future lithography, enormous exertion is put into the development of alternative fabrication technologies in particular for micro- and nanotechnologies that are capable of measuring and patterning at the atomic scale in growing operating areas of several hundred square millimetres. Many new technologies resulted in this process, and are promising to overcome the current limitations^1, 2, but most of them are demonstrated in small areas of several square micrometers only, using state-of-the-art piezo stages or the like. At the Technische Universitat Ilmenau, the NanoFabrication Machine 100 (NFM-100) was developed, which serves as an important experimental platform for basic research in the field of scale-spanning AFM tip-based and laser-based nanomeasuring and nanofabrication for simultaneous subnanometre measuring and structuring on surfaces up to Ø100 mm. This machine can be equipped with several probing systems like AFM, laser focus probes and 3D-micro probes as well as tools for different nanofabrication technologies like tip-based technologies, optical technologies and mechanical two-dimensional technologies in a large working range with subnanometre reproducibility and uncertainty. In this paper, the specifics and advantages of the NFM-100 will be described as well as nanofabrication technologies that are currently worked on e.g. advanced scanning proximal probe lithography based on Fowler-Nordheim-electron-field emission, direct laser writing and UV-nanoimprint lithography.

https://doi.org/10.1117/12.2551044

Pabst, Markus; Darnieder, Maximilian; Theska, René; Fröhlich, Thomas
Measuring and adjusting the stiffness and tilt sensitivity of a novel 2D monolithic high precision electromagnetic force compensated weighing cell. - Boulder, Colo. : NCSL International. - 1 Online-Ressource (1 Seite)Publikation entstand im Rahmen der Veranstaltung: Metrology in motion : NCSLI workshop & symposium, August 24-29, 2019

Further improvements in high precision mass comparison are a recent issue in the dissemination chain of the mass standard. One of the most precise methods of mass comparison is achieved by the use of high precision electromagnetic force compensated (EMFC) weighing cells as part of mass comparators. The mechanics of EMFC weighing cells are based on compliant mechanisms with concentrated compliances in form of flexure hinges. Total mechanical stiffness and tilt sensitivity are limiting factors with regard to the resolution of EMFC weighing cells. In order to optimize their performance, the stiffness and the tilt sensitivity of the systems need to be minimized. Due to manufacturing restrictions and robustness requirements, a further reduction of the thickness of the pivots is not desirable. In this paper, an alternative to reduce stiffness and tilt sensitivity by adding trim weights in combination with an astasizing adjustment is presented. Based on the results of the investigations, a new planar monolithic mechanism for an EMFC weighing cell is designed, providing the possibility to adjust trim masses. The new mechanism is set up and adjusted according to the developed mechanical model. A parameter combination for a total stiffness slightly above zero and a tilt sensitivity close to zero is found. For the evaluation of the adjustment success and the vacuum compatibility, the system is tested under high vacuum conditions.

https://doi.org/10.51843/wsproceedings.2019.13

Vasilyan, Suren; Rogge, Norbert; Fröhlich, Thomas
Metrology in direct photon momentum measurement. - In: Messunsicherheit - Prüfprozesse 2019, (2019), S. 193-205