Hisanori Kambara

Airborne molecular contamination detection method for photomasks and ultra purging decontamination

While photomask prices continue to increase and their lifetime continues to be shortened due to molecular contamination, it is a key issue to understand the chemical mechanism of the mask damage caused by haze problem to save fabrication cost. We show a unique method for in-situ Airborne Molecular Contamination, or AMC, measurement in the mask carrier mini-environment as well as the small volume confined under the pellicle protective film. Additionally, an ultimate solution to decontaminate the photomask and surrounding environment with a vacuum purging system shows preliminary positive results on the extension of photomask life time by elimination of the haze problem cause.