Cymer, Inc.

James H Azzola

Richard C Ujazdowski

William N Partlo

Igor Vladimirovich Fomenkov

Tibor Juhasz

Tom A Watson

Herve A Besaucele

Robert G Ozarski

Alexander Igorevich Ershov

Richard L Sandstrom

Palash P Das

Richard G Morton

Richard M Ness

Thomas Patrick Duffey

Steven Merrill Harrington

Donald G Larson

Toshihiko Ishihara

David S Knowles

Paul S Thompson

Daniel Anthony Rothweil

I Roger Oliver

Robert A Shannon

Dmitry Berger

Paul R Marsden

Carl E Tedesco, Ii

A laser chamber with a circuitous gas return path dissipates shock waves. In one embodiment, the laser chamber includes a heat exchanger with a large surface area that defines an aerodynamic passage through which gas circulates in the laser chamber. The passage through which the gas circulates directs shock waves away from the discharge region so that the shock waves may dissipate elsewhere in the laser chamber. In addition, the large surface area of the heat exchanger efficiently cools the thermally energetic gas within the laser chamber. In another embodiment, ancillary chambers that are fluidically coupled to the main laser chamber are provided to permit shock waves to be directed away from the discharge area and to be dissipated within the ancillary chambers. Openings to the ancillary chambers are positioned such that shock waves generated by the electrode structure of the laser chamber may propagate directly into the ancillary chamber, where the shock waves then dissipate. Flow guides, such as blowers or flow vanes, may be provided in the ancillary chambers to generate a circulation of gas within the ancillary chambers that will support the laser chamber's flow of gas at the openings to the ancillary chambers. Thus, the circulating gas within the laser chamber remains uniform and stable.

Shock wave dissipating laser chamber

A gas discharge laser with fast response gas temperature control to maintain laser gas temperature within desired limits during burst mode operation. Preferred embodiments include a passive temperature stabilizer having fins with surface areas exposed to flowing laser gas at least equal to the surface area of the cooling fins of a laser gas heat exchanger. Preferred embodiments utilize heating elements and coolant flow control to regulate laser gas temperatures using processors programmed to anticipate idle periods.

Gas discharge laser with gas temperature control

A reliable, modular, production quality narrow-band KrF excimer laser capable of producing 10 mJ laser pulses at 1000 Hz with a bandwidth of about 0.6 pm or less. The present invention is especially suited to long-term round-the-clock operation in the lithographic production of integrated circuits. Improvements over prior art lasers include a single upstream preionizer tube and acoustic baffles. A preferred embodiment includes reduced fluorine concentration, an anode support bar shaped to reduce aerodynamic reaction forces on blower bearings, a modified pulse power system providing faster pulse rise time, an output coupler with substantially increased reflectivity, a line narrowing module with CaF prism beam expanders, a more accurate wavemeter, a laser computer controller programmed with new and improved pulse energy control algorithm.

Reliable. modular, production quality narrow-band KRF excimer laser

A laser chamber has angled reflectors that reflect acoustic and shock waves away from the laser discharge area to minimize acoustic and shock wave disturbances. The angled reflector may have different configurations to assist in the dissipation of the acoustic and shock waves. For example, the angled reflector may have a modulated reflective surface, such as having grooves or holes defined within the surface. Further, the angled reflector may have a reflective surface with acoustic and shock wave absorbing properties. The reflective surface with absorbent properties may be a felt metal or have multiple layered porous surfaces. In addition, the walls of the laser chamber may be modulated to assist in the dissipation of the acoustic waves and shock waves through absorption, scattering, and by generating interference within the reflected waves. Multiple layered porous surfaces may be used along the walls to absorb and scatter incident waves. The walls of the laser chamber may also be covered with an acoustic and shock wave absorbing material, such as felt metal. In other embodiments, the walls of the laser chamber are modulated with grooves, such as triangular or rectangular horizontal grooves, which scatter incident waves and generate interference within reflected waves.

Laser chamber with minimized acoustic and shock wave disturbances

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San Diego, CA, United States of America

James H Azzola