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:
Aug. 18, 2009
Filed:
Dec. 04, 2007
Alex Ka Tim Poon, San Ramon, CA (US);
Leonard Wai Fung Kho, San Francisco, CA (US);
Gaurav Keswani, Fremont, CA (US);
Derek Coon, Redwood City, CA (US);
Alex Ka Tim Poon, San Ramon, CA (US);
Leonard Wai Fung Kho, San Francisco, CA (US);
Gaurav Keswani, Fremont, CA (US);
Derek Coon, Redwood City, CA (US);
Nikon Corporation, Tokyo, JP;
Abstract
A gas curtain type immersion lithography apparatus has a fluid removing porous region adjacent the gas inlet to prevent evaporative cooling. The apparatus includes a substrate holder which holds a substrate having an imaging surface and a projection optical system having a last optical element. The projection optical system projects an image onto a target imaging area on the substrate through an immersion fluid filled in a gap between the imaging surface of the substrate and the last optical element. An immersion element maintains the immersion fluid in the gap. Gas is provided through an inlet into the gap. A porous region is provided adjacent the gas inlet. Immersion fluid that collects near the gas inlet is removed by the porous region.