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:
Jun. 07, 2022
Filed:
May. 24, 2021
Lasertec Corporation, Kanagawa, JP;
Haruhiko Kusunose, Yokohama, JP;
Tsunehito Kohyama, Yokohama, JP;
Lasertec Corporation, Yokohama, JP;
Abstract
Provided are an optical device capable of effectively preventing contamination and a method for preventing contamination of the same. An optical device according to an embodiment includes a light source that generates light containing EUV (Extreme UltraViolet) light or VUV (Vacuum UltraViolet) light, a chamber in which an object to be irradiated with the light is placed, an optical element placed inside the chamber to guide the light, an introduction unit that introduces hydrogen or helium into the chamber, a power supply that applies a negative voltage to the optical element in the chamber, an ammeter that measures an ion current flowing through the optical element, and a control unit that adjusts the amount of the hydrogen or the helium introduced according to a measurement result of the ammeter.