Prevention of organic contamination in lithographic systems

摘要

The reduction in molecular outgassing afforded by the high vacuum degassing of the system components and the expected outgassing of the same when employed under normal ambient pressure and purging are evaluated and discussed. The contaminant deposits that could be expected from the residual outgassing systems are evaluated. A comparison of the contamination produced by the outgassed and non-outgassed systems has been carried out and is based on the outgassing rate of a combination of devices in the compartment obtained at the end of a reasonable period of outgassing in vacuum and on the rates at the time of employment.