ZEISS EUV lithography optics

What it is

ZEISS Semiconductor Manufacturing Technology builds the optical heart of extreme ultraviolet (EUV) lithography machines made by its strategic partner ASML. Two modules matter most: the illumination system, which shapes the light and directs it onto the photomask, and the projection optics, which image the mask's pattern onto the wafer. ZEISS delivered its first series-produced EUV optics to ASML in 2012.

How it works

EUV light has a wavelength of 13.5 nanometres and is absorbed by almost everything, including glass and air. Lenses are therefore useless, and the machine works in a vacuum using mirrors. Each mirror carries up to 100 alternating layers of molybdenum and silicon, which together reflect up to 70 per cent of the light. According to ZEISS, the illumination system has around 15,000 parts and the projection optics around 20,000. The company illustrates the required flatness this way: if a mirror were scaled to the size of Germany, its largest bump would be about 0.1 mm high.

Why it stands out

Without these optics there is no EUV lithography, and without EUV lithography the most advanced microchips in phones, data centres and AI accelerators cannot be made. ZEISS, TRUMPF and Fraunhofer IOF shared the German Future Prize in 2020 for their work on the technology. The next step, High-NA EUV, raises the numerical aperture from 0.33 to 0.55 to print even finer features; ZEISS delivered its first High-NA optics in 2023. The company states it has delivered more than 300 EUV optical systems.

Where you meet it

You will never see the mirrors, but you probably carry their output. The leading chipmakers use EUV scanners for their most advanced production nodes, so the processors in recent smartphones, laptops and AI servers have been patterned with light that passed through optics made in Oberkochen, Baden-Württemberg.