Performance of a highly stable 2-kHz operation KrF laser

Abstract

In the semiconductor industry, it is one of the most important issues to reduce manufacturing cost of the semiconductor device by increasing throughput. We have succeeded in the development of the high repetition rate excimer laser technology, and obtained the prospect oflow CoO ofthe laser device. In this paper, we present the performance and advanced technologies of the newest model of the KrF excimer laser for microlithography; KLES-G2OK. The laser achieves 20 W of output power with 0.6 pm bandwidth at 2 kHz. The pulse to pulse energy stability, 3 sigma is less than 6 % and integrated energy stability is within +-.0.4% (40 pulses). By our estimation, more than 50 % of CoO of the laser device is cut by adopting developed machine compared to a present one.