Effective solution to reticle haze formation at 193nm lithography

Various studies have been published on the formation and prevention of reticle haze; however, yield loss due to reticle haze is still an issue for most of the IC makers. For a mass production IC manufacturing fab, an easy and practical solution is needed to prevent haze generation. In this study, we focus on the solution, which can be easily implemented inside production fab and does not require a total implementation of specific type of gas or equipment. A reticle carrier with purging function combining with the use of a purge station for purging and storage is used. After implementing this solution in a 12" DRAM fabrication facility, the number of wafers printed without haze development on reticles protected by this solution can be up to 150,000 wafers, and this is great achievement in help ramping up the production and also maintain high yield. This solution has been proven to be effective in reducing the generation of haze.