Patent ID: 6636546
Filing Date: 2003-10-21
Classification: H01S

Abstract:
ArF and KrF excimer laser apparatus and fluorine laser apparatus for lithography, each comprising:a laser chamber; a magnetic pulse compression circuit; a pair of laser discharge electrodes connected to output terminals of said magnetic pulse compression circuit and disposed in said laser chamber; and a peaking capacitor connected in parallel to said pair of laser discharge electrodes; wherein, when a capacity of a capacitor in a final stage of said magnetic pulse compression circuit is denoted by Cn (n is the number of stages of the magnetic pulse compression circuit); a capacity of the peaking capacitor is denoted by Cp; an inductance of a first circuit loop formed by the capacitor in the final stage and the laser discharge electrodes is denoted by Ln; and an inductance of a second circuit loop formed by the peaking capacitor and the laser discharge electrodes is denoted by Lp; a relationship between a period Tn of a waveform of an oscillating current flowing in the first circuit loop, i.e. Tn=2&pgr;{square root over ( )}(LnÃ—Cn), and a period Tp of a waveform of an oscillating current flowing in the second circuit loop, i.e. Tp=2&pgr;{square root over ( )}(LpÃ—Cp), satisfies the following condition: 5Tpand the period Tn satisfies the following condition: Tn<250 ns whereby a laser oscillating operation is performed by at least 2.5 cycles of an oscillating current flowing between the laser discharge electrodes.