High transmission pellicles for extreme ultraviolet lithography reticle protection

Abstract

The authors present the results of a full-field extreme ultraviolet (EUV) pellicle for reticle protection and defect mitigation. Based on novel microelectromechanical systems based fabrication, it comprises a 50 nm Si membrane attached to a wire-grid. Two types of pellicle fabrication techniques are described. The authors present the first actinic results of extreme ultraviolet lithography reticle with pellicle exposed on IMEC Advanced Demo Tool. The impact of different pellicle types on imaging is evaluated as a function of pellicle standoff distance and mesh geometry. A new prototype pellicle has been developed with a measured transmission of 82% in EUV. Actinic exposures are complemented with aerial image modeling, thermal analysis, vacuum cycling, resist outgas tests, and >5 g repeated scan cycle robustness tests.