I was under the impression that electron beam could fundamentally get much smaller than light (electrons are “smaller” than photons in some funky physics sense), but was just really slow.

Also (fuzzy memories of semiconductor classes, but) the size doesn’t tell the whole story, right? With photons I’m under the impression that the wavelength of the light is much higher than the feature size, so they have to do funky things with the masks to make it all work out. Playing with interference or whatever. (Someone who knows more about this can feel free to embarrass me, I’m sure it will be educational!)

Electrons are relatively speaking more like the nice little billiards ball thwacking away at the SI that we like to imagine.