EUV pellicles have been enabled to provide customers with defect protection for EUV reticles. However, due to the absorption that is much higher than for DUV pellicles, using the pellicle has certain disadvantages. Most significant is the reduction in throughput caused by the absorption of EUV photons in the pellicle. This leads to a customer decision to use a pellicle and accept the reduced throughput, or to not use a pellicle and have additional inspection steps to check the cleanliness of the EUV reticle. These tradeoffs vary by customer and use case. This study addresses the balance of factors for using or not using a pellicle through a cost comparison.
With the introduction of the NXE:3400B scanner, ASML has brought EUV to High-Volume Manufacturing (HVM). In this context, ASML is pursuing a dual-path approach towards zero reticle defectivity: EUV-compatible pellicle or zero particles towards reticle by advanced particle contamination control. This paper will focus on the latter approach of advanced particle contamination control and will show that we are able to reduce particle contamination towards reticle to a level that is compatible with HVM requirements for sub-10nm node lithography.