For EUV, yeah. That shit's tricky.

The wiki page on EUV is uncharacteristically excellent.

https://en.wikipedia.org/wiki/Extreme_ultraviolet_lithograph...

> Since the optics already absorbs 96% of the EUV light, [...]

WTF!? Why? Is there any hope for better optics?

Mirrors on EUV machines are already the type that exceeds reflectivity of all mirrors ever produced.

That's why you have to build fabs around a multi-megawatt laser source.

The only known hope going forward are photonic crystal mirrors

But, why does 96% of the energy gets absorbed?

Each mirror absorbs about 30% of the EUV incident upon it (and the mask counts as a mirror). With about 9 total mirrors on the path, you're down to 0.7^9 ~= 4% of the initial light left.

Because everything absorbs EUV light. Every element out there has has bandgap wide enough for EUV