Hirotoshi Inoue

Ultra line-narrowed ArF excimer laser G42A for sub-90-nm lithography generation

193-nm lithography is going to move from pre-production phase to mass production phase and its target node become narrowing from 90 nm to 65 nm. In these situations, the laser manufacture needs to provide the high durable ArF excimer laser, which has superior spectrum performance. Gigaphoton has already introduced 4 kHz ArF laser (model G41A) to 193-nm lithography market, which produce 20 W and spectrum bandwidth of 0.35 pm (FWHM). G41A has showed high reliability and long lifetime over 5 billion pulses. In this paper, we report on the 4 kHz ArF excimer laser for mass production, model G42A, which has 20 W, spectral bandwidth less than 0.3 pm (FWHM) and a spectral purity less than 0.75 pm (E95).

Highly durable 4-kHz ArF excimer laser G42A for sub-90-nm lithography

Mass production in 193 nm lithography is now starting and its target node is moving from 90 nm to 65 nm. The main performance requirement of ArF excimer laser in this situation is high power with ultra narrow spectrum for higher throughput. The other hand, higher reliability and lower cost of ownership (CoO) are strongly hoped in mass production because CoO of ArF excimer laser is still higher than that of KrF excimer laser. We have already reported the 4 kHz ArF excimer laser for mass production, model G42A, which has an 20 W of average power, spectral bandwidth less than 0.3 pm (FWHM) and a spectral purity less than 0.75 pm (E95). We applied some technologies to G42A for achieving the high reliability and long lifetime. As a result, G42A showed the stable performance during the lifetime of over 10 billion pulses. In this paper, we report the long-term stability of G42A. And also, we introduce the reliability data of G40A series, which is the previous 4 kHz ArF excimer laser model.