Sputter deposition of nm-thick films for passivation of organic pellicles

Pellicles are critical to the 157 and 193 nm lithography technology. The polymeric pellicles are prone to contamination of environment, which may shorten their lifetimes. In this paper, authors passivated pellicles with various nm-thick thin films deposited by the room-temperature sputtering method. The pellicles were investigated for its light transmission efficiency and surface bond structure change. The environmental influence test was carried out by exposing the pellicle to a high-humidity, high-temperature condition. The result showed that a proper coating layer could protect the pellicle from environmental contamination while keeping the light transmittance loss low.