AziTrim: scia Systems develops an innovative process chain for the Production of SRG
scia Systems GmbH is partner in the funded joint project AziTrim, a research initiative aimed at developing an optimized process chain for the fabrication of variably tilted surface relief gratings (SRGs) using ion beam etching. The project runs from April 2025 to February 2028 and is being carried out in collaboration with LSA GmbH Wolkenstein and the Fraunhofer Institute for Electronic Nanosystems (ENAS) in Chemnitz.
SRGs are diffractive optical elements used as waveguides in augmented reality glasses. They enable virtual information to be displayed in the user’s field of view without blocking the view of the real environment. The fabrication of such structures requires precise ion beam etching at variable angles—a process that, with currently available equipment, requires complex intermediate steps and multiple cycles of loading and unloading the substrates.
The goal of AziTrim is to overcome these limitations by creating a new, uninterrupted process chain. The core of the project is the combination of a newly developed 5-axis motion system and a rotatable substrate holder, along with processing using a focused ion beam of high density, known as ion beam trimming.
scia Systems plays a key role in this process, providing simulation-based development and construction of the fine-beam ion source. We are also responsible for implementing and demonstrating the entire process chain in a test system based on the scia Trim 200 — scia Systems’ production-proven system for precise surface processing.
The new ion source is designed to generate a focused ion beam with a half-width of 1.5 mm at a beam current of 0.75 mA, which is sufficient for efficient etching without additional masking steps. In addition, reactive etching processes are being studied to further increase the etch rate for high-refractive-index materials, such as SiO₂, Si₃N₄ and TiO₂.
The development of an efficient new process chain is expected to result in a finished production system after the project has concluded. This will expand scia Systems’ product portfolio and strengthen our market position in the future.
Summary
Title:
Novel process chain for the fabrication of variably oriented grating structures via ion beam etching using a focused ion beam source on various substrates
Joint Project Partner:
- Fraunhofer-Institut für Elektronische Nanosysteme Chemnitz (ENAS)
- LSA GmbH Wolkenstein
- scia Systems GmbH Chemnitz
Project objective:
Development of a new, continuous process chain for the high-precision ion-beam trimming of surface relief grating structures with varying slant angle, utilized as waveguides in augmented reality glasses.
More Information
Ion Beam Technology for Slanted Surface Relief Gratings
scia Systems provides technologies and process equipment for the production of augmented and mixed-reality devices
White Paper: Improving Surface Relief Gratings: Multi-Depth Approaches at Different Angles for NIL Master Stamp Production
For the development of lightweight near-eye displays, SRGs are employed to couple light from the source into the waveguide and then guide it out toward the eye. This study demonstrates how reactive ion beam trimming can be utilized to produce slanted surface relief gratings, featuring different grating geometries in terms of width and pitch suitable to the specific requirements of nanoimprint lithography.