US Patent No. 10,512,148

SYSTEM AND METHOD FOR GENERATING EXTREME ULTRAVIOLET LIGHT EMPLOYING LASER PULSE INCLUDING PEDESTAL


Patent No. 10,512,148
Issue Date December 17, 2019
Title System And Method For Generating Extreme Ultraviolet Light Employing Laser Pulse Including Pedestal
Inventorship Hitoshi Nagano, Himeji (JP)
Yasunori Wada, Chigasaki (JP)
Tatsuya Yanagida, Hiratsuka (JP)
Osamu Wakabayashi, Hiratsuka (JP)
Assignee Gigaphoton Inc., Tochigi (JP)

Claim of US Patent No. 10,512,148

1. A system for generating extreme ultraviolet light, the system comprising:a master oscillator configured to output a laser beam pulse, the laser beam pulse having a waveform including a first portion and a second portion following the first portion;
an optical element positioned in a beam path of the laser beam pulse, the optical element configured to transform the waveform of the laser beam pulse to a second waveform, the second waveform including a pedestal and a peak, the pedestal being formed by transformation of the first portion to the pedestal by the optical element, and the peak being the second portion;
an amplifier including a gain medium, the amplifier configured to amplify the pedestal and the peak to form an amplified pedestal and an amplified peak; and
the amplified pedestal and the amplified peak containing sufficient energy to turn a target material into a plasma that emits EUV light.