US Patent No. 10,172,224


Patent No. 10,172,224
Issue Date January 01, 2019
Title Extreme Uv Light Generator
Inventorship Takayuki Yabu, Oyama (JP)
Hirokazu Hosoda, Oyama (JP)
Takuya Ishii, Oyama (JP)
Assignee Gigaphoton Inc., Tochigi (JP)

Claim of US Patent No. 10,172,224

1. An extreme ultraviolet light generation apparatus comprising:a chamber in which extreme ultraviolet light is generated from plasma, the plasma being generated by irradiating a target supplied into the chamber with a laser beam;
a target generator configured to supply the target into the chamber as a droplet;
a droplet measurement unit configured to measure the droplet supplied from the target generator into the chamber; and
a shielding member configured to shield the droplet measurement unit from electromagnetic waves emitted from the plasma,
the droplet measurement unit including:
a light source configured to emit continuous light to the droplet;
a window provided in the chamber and configured to allow the continuous light to transmit therethrough; and
an optical sensor configured to receive the continuous light via the window, and
the shielding member including a shielding body provided on the chamber side with respect to the window configured to cover an optical path of the continuous light and having a light passing opening for passing the continuous light therethrough, and the shielding member is provided within the interior of the chamber, configured separately from a wall that constitutes the chamber.