3D mask effects of absorber geometry in EUV lithography systems
Autor: | Bruce W. Smith, Zac Levinson, Riaz R. Haque |
---|---|
Rok vydání: | 2016 |
Předmět: |
010302 applied physics
Physics Diffraction business.industry Extreme ultraviolet lithography Phase (waves) Geometry 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Ray law.invention Lens (optics) Optics law Extreme ultraviolet 0103 physical sciences Optoelectronics 0210 nano-technology business Focus (optics) Aerial image |
Zdroj: | Extreme Ultraviolet (EUV) Lithography VII. |
ISSN: | 0277-786X |
Popis: | The non-zero chief ray angle at the object (CRAO) in EUVL systems introduces azimuthally asymmetric phase shifts. Understanding and characterizing these effects is critical to EUVL system and mask design. The effects of 3D mask absorber geometry on diffraction phase were examined through rigorous simulation. The diffraction phase distribution was split into even and odd components to enable analogies between the well-known effects of lens aberrations and EUV 3D mask effects. Specifically, this analysis reveals that the odd component of the phase distribution is non-zero in off-axis optical systems. We have found that 3D mask effects in EUVL systems can be partially compensated in the pupil plane to minimize aerial image effects, such as best focus shifts, horizontal-vertical CD bias, and image placement error. |
Databáze: | OpenAIRE |
Externí odkaz: |