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Study on high pressure plasma produced by ArF laser

Norio Tsuda·Jun Yamada
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Abstract

When an ArF excimer laser beam was focused in a high pressure argon gas from 50 to 130 atm, the plasma development is observed by streak camera from side window of chamber. The high pressure ArF laser plasma develops symmetrically and the plasma produced by ArF excimer laser hardly develops as compared with the plasma produced by XeCl. The photon energy of ArF laser light is higher than the XeCl laser. The transmittance of ArF laser light was measured. Almost all the laser light is transmitted as the frequency of laser light is higher than the plasma frequency, and the energy of laser light is hardly working for plasma development. The backward and forward plasma development produced by the ArF laser was calculated by the breakdown wave and the radiation supported shock wave, which agreed with the experimental one. The backward development mechanism of high pressure ArF plasma is same as one of plasma produced by XeCl laser. However, the forward development mechanism of ArF plasma differs from one of plasma produced by XeCl laser.

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Norio Tsuda, Jun Yamada. 2004-11-07. Study on high pressure plasma produced by ArF laser. https://arxiv.org/abs/physics/0411068

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