Reliability report of high power injection lock laser light source for double exposure and double patterning ArF immersion lithography

摘要

ArF immersion technology is spotlighted as the enabling technology for the 45nm node and beyond. Recently, double exposure technology is also considered as a possible candidate for the 32nm node and beyond. We have already released an injection lock ArF excimer laser, the GT61A (60W/6kHz/10mJ/0.35pm) with ultra line-narrowed spectrum and stabilized spectrum performance for immersion lithography tools with N.A.>1.3, and we have been monitoring the field reliability data of our lasers used in the ArF immersion segment since Q4 2006. We show GT series reliability data in the field. GT series have high reliability performance. The availability that exceeds 99.5% proves the reliability of the GT series. We have developed high power injection lock ArF excimer laser for double patterning, the GT62A (90W/6000Hz/15mJ/0.35pm(E95)) based on the GigaTwin (GT) platform. Number of innovative and unique technologies are implemented on GT62A in order to reduce running cost of laser. We have introduced unique technology to enable 40 billion pulse lifetime of laser chambers to drastically reduce running cost. In addition, we have improved lifetime of Line Narrowing Module significantly by changing optical path. Furthermore, the extension of gas refill intervals was achieved by introducing new gas supply module and sophisticated gas control algorithm. We achieved the reduction of operation cost and down time by introducing these three technologies.