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A lot of people don't understand just how massive a shift EUV represents (this isn't directed at you in particular btw, this is just for people's general knowledge). You're going from using a 193nm laser with refractory optics and immersion lithography to a 13.5nm beam which is literally absorptive by just about everything. That means first and foremost we go from using refractory optics to only reflective optics that are composed of 20+ alternating layers of molybdenum and silicon just to make sure we're managing to reflect most of the light. Immersion lithography is out because water absorbs this wavelength as well. These new machines also have to have the entire process run in a vacuum for the same reason.
It highlights a basic fundamental principle that you cannot have your cake and eat it, too. This is much like why we cannot have a full electron beam in lithography, same principle: the more charged the particle, the more interactive and decaying it is, the less half life and refractive properties it has. You spend your energy on friction when you need it on the substrate. Components would warp from excessive wear. Have to focus an electron microscope for calibration? By the time setup is complete, you just punch a hole in the looking glass. It has no refractory tolerance, its like harnessing laser illumination for photography, scouring the template in the process.
Personaly, I don't look forward to DUV to end. Look at the statistics,
- We barely have enough photoscanners to run refractory lithography,
- By the time EUV kicks in, against disbelief, proportionally, we will initially need an inversely high count of photoscanners by its volume production ramp standards because we would have now switched to reflective lithography and excess component wear will surge demand for the pellicles like flies drop near an electric fly killer.
- Pellicle test stations, both used in DUV and EUV, will be much more important - their production units are already booked for the next 2.5 years - and with the rapid turnover of pellicles in EUV, rather than DUV, will highlight this exacerbation of EUV's inherent incompatibility to volume production even more.
Also, vacuum environment is a joke. Electron beams aren't light, per say, they're electromagnetic radiation. The moment they hit the pellicle, high energy radiation is reflected back from the layers, if only it was just as powerful and noninteractive. There is no vacuum for radiation. Maybe we can have quantum MR 'decapacitor' rings around the chamber stepping down the energy states within the cabinet in the future, though. I'm not discounting electron state deescalation, or its more general expression quantum magnetic effect - has been done in nuclear physics - however I have worries; eventhough suppressed electrons aren't helping to cool off the pellicle, that heat is still building up and will sooner or later warp the thing unless production slows. Now, the important question is: how do you cool, if you are in a vacuum?