Mass production adoption of EUV pellicle: methodology for evaluation and validation

An extreme ultraviolet (EUV) pellicle is a thin film used to protect the surface of photomask patterns in exposure devices. Its performance is determined by factors such as EUV transmittance, physical strength, and thermal stability. However, over time, pellicles are continuously exposed to high temperatures and accelerations, which can lead to degradation of performance and increased risk of destruction. Therefore, various analytical techniques have been proposed to predict the lifetime of EUV pellicles. One of them is the development of on-site heating transmission electron microscope analysis technology, which can analyze the real-time change of thin film properties in a high-temperature environment. This technique can analyze the stress of thin film membranes directly related to the deformation or destruction of the film. Another approach proposes a non-destructive verification method that enables the mass application of EUV pellicles in EUV lithography through Raman analysis of defects double resonance in the EUV pellicle membrane. This can predict deformation or destruction of the film by analyzing the degree of damage and stress of the membrane during the use of the EUV pellicle membrane. Furthermore, we can evaluate the mass production feasibility of EUV exposure by analyzing the outgassing of EUV pellicles in high-temperature vacuum environments.