extreme ultraviolet (light) (EUV)

Extreme ultraviolet light(EUV) is extremely short-wavelength light with a wavelength of 10 nm to 20 nm. This extremely short wavelength is used in optical lithography, Extreme Ultraviolet Lithography( EUVL), for the fabrication of ultra-fine chip structures.

In classical chip fabrication, lithographic templates were exposed to deep ultraviolet( DUV), an ultraviolet light with wavelengths of 193 nm or 248 nm. For fabrication of finer chip structures with higher integration density, light with much shorter wavelengths is used. Extremely short-wave UV light is predestined for this application. Since EUV radiation is absorbed by all materials, even air, the lithographic processes can only be carried out in a vacuum.

UV light and Extreme Ultraviolet (EUV) with shortest wavelengths

The EUV light needed for EUV lithography is generated by hot ionized plasma, and at temperatures of about 200,000 °C. The gas is irradiated by high- power lasers. While current technologies can produce current path structures of 45 nm with UV lasers, EUV radiation can realize current paths with structure widths of less than 10 nm. Even narrower structure widths are possible with beam focusing using numerical aperture. Corresponding lithographic systems achieve structure widths of less than 2 nm.