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:
Jul. 29, 2008
Filed:
Sep. 28, 2004
Uwe Paul Schroeder, Hopewell Junction, NY (US);
Oliver Broermann, Dresden, DE;
Uwe Paul Schroeder, Hopewell Junction, NY (US);
Oliver Broermann, Dresden, DE;
Infineon Technologies AG, Munich, DE;
Abstract
A lithographic mask having a mask substrate () and a patterned mask layer () which includes mask structures () and can be transferred by lithography to a further substrate is disclosed. With masks of this type, it is customary for a protective layer to be provided in the form of a membrane positioned at a distance from the mask layer (), in order to keep impurity particles or other impurities away from the focal plane of the mask layer (). According to the invention, the protective layer () is applied in liquid form directly to the mask structures () and fills up spaces between the mask structures (). Then, the protective layer (), while it is still in the liquid state, is covered with a plane-parallel plate. The continuously dense protective layer () which is formed in accordance with the invention is even more reliable in preventing impurity particles or impurities () from penetrating into spacers between the structures () of the mask layer (). The impurity particles or impurities () can only be deposited on the outer side () of the protective layer (), at a still greater distance from the focal plane.