Extreme Ultraviolet (EUV)

Extreme Ultraviolet Lithography (also known as EUV or EUVL) is a next-generation lithography technology using the 13.5 nm wavelength. EUV is a significant departure from the deep ultraviolet lithography used today. All matter absorbs EUV radiation. Hence, EUV lithography needs to take place in a vacuum. All the optical elements, including the photomask, must make use of defect-free Mo/Si multilayers which act to reflect light by means of interlayer interference; any one of these mirrors will absorb around 30% of the incident light. This limitation can be avoided in maskless interference lithography systems. However, the latter tools are restricted to producing periodic patterns only.
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