Research

EUV plasmas and soft X-ray plasmas can easily achieve high light intensity and are used for semiconductor lithography and material diagnostics. On the other hand, for optimization (wavelength selectivity and high efficiency), control of the electronic state (electron density and electron temperature) of the plasma is necessary, but measurement of the electronic state has not been achieved yet with conventional techniques, and the electronic state had been unknown. The feature of this technology is that it enables detailed measurement of electron density and temperature in EUV plasmas by laser scattering measurement (Thomson scattering method) using a unique spectroscopic system. This makes it possible to develop light sources based on an understanding of the electronic state, which is the root of the mechanism by which plasma emits light.