Translator Disclaimer
17 December 2003 Rigorous simulation of defective EUV multilayer masks
Author Affiliations +
One of the hot topics in the Extreme Ultra-Violet (EUV) mask fabrication process is the requirement to produce multilayer blanks without any printing defects. As the potential of experimental studies is still limited, a predictive simulation of EUV lithography is an important step on the way to meet this requirement. The simulator tool SOLID-EUV is extended to deal with defective multilayers. The simulation is divided into two regions, the finite-difference timendomain (FDTD) method for the absorber part and the simulation of the multilayer reflectivity by the Fresnel-method. To take the defects into account the multilayer is divided into segments, which include the defect and the reflectivity is calculated for each segment. For calculating the multilayer stack for each segment the defects are assumed to be Gaussian shaped. For the complete computation of the reflected light from the EUV mask a coupling of the two methods is realized. This paper presents case studies using the lithography simulator tool SOLID-EUV with the new defective multilayer simulation part, to analyze the printability of defects. The impact of the defect size, horizontal and vertical defect position within the multilayer, and the influence of the layer deposition process is analyzed. The most influential defect parameters are identified. One defect with an influence which tends to be printed is taken and combined with typical mask structures, such as isolated lines, lines and spaces and contact holes. The process windows of the mask structures for various defect positions are analyzed. These simulations can be used to develop strategies to handle such defects.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Christoph Sambale, Thomas Schmoeller, Andreas Erdmann, Peter Evanschitzky, and Christian K. Kalus "Rigorous simulation of defective EUV multilayer masks", Proc. SPIE 5256, 23rd Annual BACUS Symposium on Photomask Technology, (17 December 2003);

Back to Top