Patent ID: 6785316
Filing Date: 2004-08-31
Classification: G03F,H01S

Abstract:
An illumination photolithography system for producing structures on a workpiece, comprising:an excimer or molecular fluorine laser system; and an imaging system for delivering output pulses emitted from said laser system to said workpiece, wherein said laser system comprises: a discharge chamber filled with a laser gas mixture; a plurality of electrodes within said discharge chamber connected to a pulsed discharge circuit for energizing the gas mixture; and a resonator including the discharge chamber for generating an output laser beam, wherein said pulsed discharge circuit comprises: a high voltage power supply; a main storage capacitor which is charged by the power supply; a pulse compression circuit; and a switch for permitting said storage capacitor to discharge through the pulse compression circuit to said electrodes, wherein said pulse compression circuit comprises: one or more pulse compression stages each including a stage capacitance and being separated by a stage inductance, wherein a final stage capacitance is provided by: a set of peaking capacitors connected to said electrodes through a first inductance; and a set of sustaining capacitors connected to said electrodes through a second inductance greater than the first inductance by at least 25%, such that current pulses through the discharge are temporally extended due to the first and second inductances differing substantially such that different electrical charges are applied to the electrodes from the set of peaking capacitors and from the set of sustaining capacitors across a temporally extended range wherein first electrical charges applied to the electrodes from the peaking capacitors initiate the discharge and different, delayed, second electrical charges applied to the electrodes from the sustaining capacitors temporally extend the discharge, and an amplified spontaneous emission (ASE) level in said pulses is reduced thereby enhancing spectral purity of said output beam.