Damage testing of pellicles for 193-nm lithography

We investigated laser-induced damage of pellicles for 193-nm lithography. We surveyed 193-nm-optimized material from three pellicle suppliers. Pellicles were irradiated under realistic reticle plane conditions (0.04 mJ/cm 2 /pulse - 0.12 mJ/cm 2 /pulse for up to 100 million pulses). Pellicles from two suppliers were found to meet lifetime requirements of the industry. Pellicles from the third supplier do not appear to meet the lifetime requirements. We present fluence scaling of pellicle damage and discuss effects of the ambient on pellicle degradation rates. We present results of the outgassing studies of pellicle material under irradiation using a separate gas chromatograph-mass spectrometer-based detection apparatus. From the results of these studies, we suggest possible photochemical pathways for pellicle degradation as a function of ambient.