T PB Direct Problem: Diffraction by Grating Structures. 1 W - PowerPoint PPT Presentation

Outline Outline T PB Direct Problem: Diffraction by Grating Structures. 1 W eierstraß-Institut�für�Angewandte�Analysis�und�Stochastik Reconstruction of Periodic Surface Structures 2 H. Groß, A. Rathsfeld Sensitivity Analysis 3 Numerical Aspects of the Scatterometric Tasks of Sensitivity Analysis Measurement of Periodic Surface Structures Uncertainty Estimates for Derived Values Stochastic Geometries 4 Conclusions 5 Numerical Aspects of the Scatterometric Measurement of Periodic Surface Structures M37, July 21 1 (44) Numerical Aspects of the Scatterometric Measurement of Periodic Surface Structures M37, July 21 2 (44) . Direct Problem: Diffraction by Grating Structures. Direct Problem: Diffraction by Grating Structures. incoming field reflected modes Lithography y (E ,H ) i i θ photoresist chip production like old-fashioned photography: z photoresist layer illuminated by light scattered from mask, x development: baking and etching procedures − → chip light source wafer chrome photo resist silicon oxide mask transmitted modes standard test configurations: periodic gratings (similarly, biperiodic surface structures) – periodic line-space structure (lines formed by bridges with details of surface geometry in size of wavelength trapezoidal cross section) – biperiodic array of trapezoidal blocks resp. holes Numerical Aspects of the Scatterometric Measurement of Periodic Surface Structures M37, July 21 4 (44) Numerical Aspects of the Scatterometric Measurement of Periodic Surface Structures M37, July 21 5 (44)

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