Commentary of material science in EUV technology

Here, we will explain the information necessary for understanding EUV mirrors.

The diagram above shows a schematic representation of the Mo/Si multilayer mirror introduced on the website.EUV light incident at a specific angle is reflected at the Mo/Si interface. Here, if the periodic length is set so that the phase of λ/2 (λ=13.5 nm) passes through one period of Mo and Si, the phases of the reflected light at each interface are aligned and the reflectance is increased. Although the difference in refractive index between Mo and Si is small, a multilayer structure with 20 periods or more is used to achieve a high reflectance. The physical properties of each material for EUV light are explained below.

１．Refractive index parameters δ, β of each material for EUV light

https://drive.google.com/file/d/1qqJ-HyeceJNdc3hIGXpRuJsneudGoKBn/view?usp=share_link

２．Optical properties of Si for EUV light

https://drive.google.com/file/d/1NurOA_CWYsHvuonsx2x6XiNyMHXKYYK6/view?usp=share_link

３．Optical properties of Zr for EUV light

https://drive.google.com/file/d/19uvZ8YF6__IePkhax8kI9ZHHqSBmFgy7/view?usp=sharing

４．Optical properties of Mo for EUV light

https://drive.google.com/file/d/1nUPZOPsqBxmU9zoLYoCh3lWC3laMf9Em/view?usp=share_link

5．Optical properties of Ru for EUV light

https://drive.google.com/file/d/1cJkcD_5HorRKtDDMqggKGBIqfLGHYaVg/view?usp=share_link

６．Summary of optical properties of 5th period metals

https://drive.google.com/file/d/15FZngPLjJJ-ojbYXT3d7pS3BF4iVUTeR/view?usp=share_link