Acoustic signal to control laser structuring processesSNI INSight May 2021
As part of the Nano Argovia project LanakPro, teams from the University of Applied Sciences and Arts Northwestern Switzerland (FHNW) are working with the industrial partner Orvinum AG (Magden) to achieve effective and reliable control of laser nanostructuring processes. The planned instrument will use acoustic signals that provide quick and reliable information on the progress and quality of processing, allowing researchers to control the nanostructuring process.
There is an increasingly wide range of applications for materials whose surfaces exhibit special properties thanks to the presence of miniscule structures. These microstructures and nanostructures are often produced using lasers, but the structuring processes require elaborate monitoring and control. Ideally, there would be an instrument that provided automated process monitoring and independent tracking in order to pave the way for widespread applications in areas such as microfluidics, medical engineering or sensor technology.
Recording an acoustic fingerprint
Under the leadership of Armin Stumpp (FHNW), the team behind the Nano Argovia project LanakPro is now using acoustic signals to enable control of the structuring process. To do this, they first record an “acoustic fingerprint” of the optimum structuring process, which can then be compared with the true signal pattern in real time when it comes to measuring a real sample. Thanks to new, fast and robust algorithms and an underlying database, it will then be possible to register deviations immediately, intervene in the process and make the necessary adjustments.
The participating researchers from the teams led by Armin Stumpp, Professor Matthias Hoebel, Claudio Furrer (all of the FHNW School of Engineering), Dr. Frank Dieterle (FHNW School of Life Sciences) and Dr. Markus Ehrat (Orvinum AG) are developing this instrument in order to improve development times and processing costs for laser nanostructuring processes. Their focus is on applications with particularly stringent requirements in terms of processing quality and efficiency, especially those involving materials such as glass or plastics and sensitive substrates such as ceramics.
“The process monitoring developed as part of this project will have a beneficial impact on the precision, robustness and duration of processing and therefore open up new applications for laser nanostructuring.”
Markus Ehrat, CSO of Orvinum AG
Multiple steps are required
Over the next few months, the project team will now select suitable sensors, taking care to ensure that they offer a high level of sensitivity in the relevant frequency ranges. The team will then record the acoustic fingerprints for various materials during laser structuring and filter out key signals for the process sequence before carrying out the first laser structuring processes with acoustic monitoring.
Based on this work, the researchers then plan to develop a device that allows even users who lack special training to carry out sophisticated laser processes for various substances quickly and in a reproducible manner.