https://doi.org/10.1051/epjconf/201921501001
Coherent Ray Tracing Simulation Of Non-Imaging Laser Beam Shaping With Multi-Aperture Elements
1
SUSS MicroOptics SA, CH-2068 Hauterive, Switzerland
2
NAM, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
* Corresponding author: raoul.kirner@suss.com
Published online: 10 September 2019
The application of laser light sources for illumination tasks like in mask aligner lithography relies on non-imaging optical systems with multi-aperture elements for beam shaping. When simulating such systems, the traditional approach is to separate the beam-shaping part (incoherent simulation) from dealing with coherence properties of the illuminating laser light source (diffraction theory with statistical treatment). We present an approach using Gaussian beam decomposition to include coherence simulation into ray tracing, combining these two parts, to get a complete picture in one simulation. We discuss source definition for such simulations, and verify our assumptions on a well-known system. We then apply our approach to an imaging beam shaping setup with microoptical multi-aperture elements. We compare the simulation to measurements of a similar beam-shaping setup with a 193 nm continuous-wave laser in a mask-aligner configuration.
© The Authors, published by EDP Sciences, 2019
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
