There are many applications where fast, accurate light scattering from EUV photomasks must be computed, including inverse mask design, actinic die-to-database inspection, and actinic scatterometry. However, so-called mask 3D effects make this calculation much more challenging than traditional optical lithography. These 3D effects arise from the optically thicker absorber, the lack of illumination symmetry about normal incidence, the multilayer mirror reflection function, and multiple scattering off the absorber. In this paper, we explore using actinic scatterometry at the CXRO EUV reflectometer to characterize both the multilayer and absorber of an EUV photomask; we then introduce the Multilayer Multiple Scattering (MLMS) mathematical model that conveniently separates the effects of the multilayer and the absorber and explore the implications of this model on the origins of mask 3D effects.
Stuart Sherwin, Andrew Neureuther, and Patrick Naulleau, "Actinic EUV scatterometry for parametric mask quantification," Proc. SPIE 10583, Extreme Ultraviolet (EUV) Lithography IX, 105831G (Presented at SPIE Advanced Lithography: March 01, 2018; Published: 19 March 2018); https://doi.org/10.1117/12.2299271.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the conference proceedings. They include the speaker's narration along with a video recording of the presentation slides and animations. Many conference presentations also include full-text papers. Search and browse our growing collection of more than 12,000 conference presentations, including many plenary and keynote presentations.