Perspectives of reactive ion etching of silicate glasses for optical microsystems
Citation
Weigel, C., Brokmann, U., Hofmann, M., Behrens, A., Rädlein, E., Hoffmann, M., Strehle, S., & Sinzinger, S. (2021). Perspectives of Reactive Ion Etching of Silicate Glasses for Optical Microsystems. Journal of Micro/Nanolithography, MEMS, and MOEMS, 1(4), 040901.
Additionally, the excerpts provide an email address for the corresponding author: christoph.weigel@tu-ilmenau.de
Keywords
- optical microsystems
- diffractive optics
- silicate glasses
- reactive ion etching
- optical micro- and nanostructures
- three-dimensional microstructuring
Brief
This article reviews the use of reactive ion etching (RIE) for fabricating micro-optical components, particularly emphasizing the potential of 3D structuring and the processing of chemically complex silicate-based substrates.
Summary
This article, published in 2021 in the Journal of Micro/Nanolithography, MEMS, and MOEMS, reviews the use of reactive ion etching (RIE) for fabricating micro-optical components and systems. The authors emphasize the challenges of RIE for complex optical materials like silicate glasses and call for a deeper understanding of the chemical and physical processes involved to improve this technology.
Here are the key takeaways:
- RIE is well-suited for creating micro-optical elements: The technology is successfully used to fabricate high-precision microstructured optical surfaces for applications like beam shaping, beam splitting, imaging, and illumination.
- Silicate glasses present unique challenges for RIE: Compared to simpler materials, etching silicate glasses is more complex due to their high binding energy, heterogeneous character, and the generation of non-volatile reaction products.
- The article showcases the successful etching of various silicate glasses: The authors present their findings on deep etching fused silica, microstructuring ultra-low expansion glasses, creating 3D microstructured GRIN lenses, and plasma-supported etching of photosensitive glasses.
- The authors also explore the fabrication of 3D microresonators: They demonstrate a method for making high-Q whispering gallery mode resonators using silicon micromachining followed by oxidation to form smooth, low-loss silica layers.
The article concludes by advocating for more research into RIE processes, particularly for complex silicate glasses. A deeper understanding of the interactions within the plasma and at the material interface is crucial to further advance the possibilities of RIE for 3D micro- and nanostructures in optical microsystems.