Scientists and students from TU Ilmenau submitted a total of 55 creative entries from research and technology to this year’s photo competition organized by the Förderverein für Mikround Nanotechnologien Ilmenau e.V. and the Institute for Microand Nanotechnologies IMN MacroNano . They were judged by Karin Wedrich from X-FAB in Erfurt, Dr. Torsten Erbe from ASML (Advanced Semiconductor Materials Lithography) NV, the world’s largest supplier of lithography systems for the semiconductor industry, and Sebastian Gropp from VDI/VDE Innovation + Technik GmbH.
"Each image provides an insight into tiny structures, surfaces or cells that would otherwise remain hidden from the human eye," says Maria Illing, a consultant at the IMN. For example, Bernd Sprenger’s 3rd prize-winning image "Coiled light" shows a coiled filament in a standard household light bulb magnified one hundred times. The staff member of CiS Forschungsinstitut für Mikrosensorik GmbH, an affiliated institute of TU Ilmenau, took the picture using a scanning electron microscope (SEM).
Also using an SEM, Ningxiang Wu, a research associate at the Applied Nanophysics department, visualized a stack of nanosheets formed by electrodeposition on the surface of carbon paper. "The fascinating thing about it," says Maria Illing: "In his 2nd prize-winning image, this stack looks like a neural network."
One image from 170 individual shots
Sebastian Bohm captured half of a tiny micropump in dazzling colors and was awarded first prize in the NanObjectives competition. The pump, which the physicist co-developed and manufactured as part of a cooperation project between TU Ilmenau and 5microns GmbH in the Central Innovation Program for SMEs (ZIM), does not require any moving parts. Instead of mechanical pistons or diaphragms, the liquid itself does the pumping work in the innovative micropump. "In my picture, you can see the pump chamber and the microfluidic valves, known as Tesla valves, on a silicon wafer," says the recently graduated physicist: "The second part, which is necessary for the construction of a functioning pump and is bonded to the substrate shown, is not visible in the picture."For the image, Sebastian Bohm placed five drops of water with a volume of around one microliter in the pump chamber:
For this, the surface of the imaged silicon wafer first had to be hydrophobized, i.e. treated so that it is water-repellent. To achieve this, I coated the substrate with a layer of a polymer just a few nanometers thick. This allows water droplets to settle on the surface without wetting and running off the surface.
The resulting image is made up of around 170 individual images, which the young scientist combined using a special recording and image processing technique known as "focus stacking" to create a single image with an exceptionally high depth of field. In order to create the bluish background light and the reflections in the water droplets, he changed the color of the LED lighting after every 60 images: "This is how the different colors in the droplets were created," explains the physicist.
The system itself, for which Sebastian Bohm developed numerical methods under the supervision of head of department Prof. Erich Runge and for the production of which he has just been awarded a doctorate summa cum laude, can be used for a wide range of applications:
For example, the micropump can be used in medical technology in pipetting robots, insulin pumps or automatic drop dosing machines, but also in the food industry - wherever precise dosing and low production costs are required.
More information about the system can be found in the publications Bohm et al. Microsyst. Nanoeng., 8, 97 (2022) and Bohm et al. Lab on a Chip, 11, 2893-2905 (2024) .
