Aerial image deformation caused by various defects of EUV pellicles

Abstract

The Critical Dimension (CD) uniformity due to the defect on the Extreme-Ultraviolet (EUV) pellicle is reported. Based on computational simulation of the aerial images for different defect size on the wafer, it is found that the size of the defect should be smaller than 2 μm for the CD uniformity of 0.1 nm. The aerial image for the different defect materials, sulfur and ruthenium, are also simulated showing that the CD uniformity does not have a noticeable dependence on the different defect materials. However, the CD uniformity is worsened with the mesh structure due to its shadow and the much smaller defects size, less than 2 μm, can be allowed. © 2014 SPIE.