The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 09, 2004
Filed:
Jul. 03, 2002
Stephan T. Melnychuk, Carlsbad, CA (US);
William N. Partlo, Poway, CA (US);
Igor V. Fomenkov, San Diego, CA (US);
I. Roger Oliver, San Diego, CA (US);
Richard M. Ness, San Diego, CA (US);
Norbert Bowering, San Diego, CA (US);
Oleh Khodykin, San Diego, CA (US);
Cymer, Inc., San Diego, CA (US);
Abstract
The present invention provides a high energy photon source. A pair of plasma pinch electrodes are located in a vacuum chamber. The chamber contains a working gas which includes a noble buffer gas and an active gas chosen to provide a desired spectral line. A pulse power source provides electrical pulses at voltages high enough to create electrical discharges between the electrodes to produce very high temperature, high density plasma pinches in the working gas providing radiation at the spectral line of the source or active gas. Preferably the electrodes are configured co-axially. The central electrode is preferably hollow and the active gas is introduced out of the hollow electrode. This permits an optimization of the spectral line source and a separate optimization of the buffer gas. In preferred embodiments the central electrode is pulsed with a high negative electrical pulse so that the central electrode functions as a hollow cathode. Preferred embodiments present optimization of capacitance values, anode length and shape and preferred active gas delivery systems are disclosed. Preferred embodiments also include a pulse power system comprising a charging capacitor and a magnetic compression circuit comprising a pulse transformer. Special techniques are described for cooling the central electrode. In one example, water is circulated through the walls of the hollow electrode. In another example, a heat pipe cooling system is described for cooling the central electrode.