Impact of the non-uniform intensity distribution caused by a meshed pellicle of extreme ultraviolet lithography
The meshed pellicle can make the intensity distribution on the wafer non-uniform. Coherence radius and mesh pitch are key factor to reduce the non-uniformity. We develop physical optics simulation to simulate non-uniformity on the wafer. The non-uniformity is directly proportional to the CDU. We can optimize the mesh parameters which can meet the CDU allowance.
meshed pellicle pellicle euvl euv pellicle mask defect control