deep ultraviolet (DUV)

Deep Ultraviolet (DUV) is short-wave UV light with a wavelength of 193 nm or 248 nm.

DUV light with these wavelengths is used in photolithography for chip fabrication because it can be used to create fine chip structures. Even finer chip structures are created with even shorter wavelengths using Extreme Ultraviolet Lithography( EUVL).

Deep Ultraviolet is a high speed lithography technique suitable for large area masks of discrete components. The ultraviolet light used for DUV lithography comes from an argon fluoride laser (ArF) or from a krypton fluoride laser (KrF). The former has a wavelength of 193 nm and the latter has one of 248 nm. The smaller the wavelength, the higher the achievable resolution. In this technique, the photomask is projected onto the wafer via an optical lens system. Higher resolution can be achieved by introducing water between the lens and the wafer, since water has a higher refractive index than air. This technique is called immersion technology.