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:
May. 29, 2007
Filed:
Jul. 01, 2005
Paul Mertens, Bonheiden, BE;
Wim Fyen, Leuven, BE;
Paul Mertens, Bonheiden, BE;
Wim Fyen, Leuven, BE;
Interuniversitair Microelektronica Centrum (IMEC), Leuven, BE;
Abstract
A method and apparatus for immersion lithography is described. The method includes positioning a semiconductor substrate under an optical immersion head assembly, providing an immersion liquid between the substrate and the optical immersion head assembly, and supplying a tensio-active gaseous substance along the perimeter of the contact area of the immersion liquid and the substrate. The immersion liquid contacts at least an area of the substrate. The tensio-active gaseous substance is chosen such that, when at least partially mixed with the immersion liquid, the mixture has a lower surface tension than the immersion liquid, thereby creating a surface tension gradient pulling the immersion liquid from the perimeter towards an inside portion of the contact area.