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:
Apr. 29, 2008
Filed:
Apr. 27, 2006
Duc Chinh Tran, Goettingen, DE;
Jesko Brudermann, Goettingen, DE;
Bjoern Mader, Hannover, DE;
René DE Bruijn, Goettingen, DE;
Juergen Kleinschmidt, Goettingen, DE;
Duc Chinh Tran, Goettingen, DE;
Jesko Brudermann, Goettingen, DE;
Bjoern Mader, Hannover, DE;
René De Bruijn, Goettingen, DE;
Juergen Kleinschmidt, Goettingen, DE;
XTREME technologies GmbH, Jena, DE;
Abstract
The invention is directed to a method and arrangements for the suppression of debris in short-wavelength radiation sources based on a plasma, particularly for EUV sources for semiconductor lithography. The object of the invention is to find a novel possibility for suppressing the particle flow (debris) from a plasma which keeps the debris away from primarily optical components located downstream without excessive attenuation of the desired radiation emitted from the plasma. According to the invention, this object is met in that a buffer gas is injected inside the filter structure of the debris filter lateral to openings that are provided for passing the radiation. The filter structure generates a flow resistance in direction of the plasma and in direction of propagation of the radiation so that an increased gas pressure of buffer gas remains limited to a defined volume layer in the debris filter relative to the pressure in the vacuum chamber, and the buffer gas exiting from the filter structure of the debris filter is sucked out of the vacuum chamber by vacuum pumps.