Yes to both of these questions. "Soft" is probably a better way to articulate this, thanks. I'm not following the explanation of this being caused by photography however. Is this specific to photography at this scale?
>"I imagine if you were to make the same device on modern tech everything would look a lot 'sharper."
I don't have an example handy however I have seen more recent micrographs and they display the same "softness" and lack of true 90 degree angles etc.
As for 'modern tech' vs. old tech, I'm referring to if you made the same size silicon structure on newer tech. When you get down to 7nm or whatever, the same problems show up (or even new ones) because the sizes get smaller. I wouldn't be surprised if the image from 1997 is 180nm or larger nodes.
Also, unlike the other replier, I don't think there's any meaningful diffraction (causing softness) by the actual SEM images... they don't use glass lenses like traditional cameras.
Yes. A smaller scale makes it worse, a larger scale makes it better.
If you reduce things enough, everything will become so blurred that you won't be able to see anything (that's why we can't photograph atoms using visible light), and if you make things large enough your camera will become the bottleneck so a very small amount of blur is added to any object, whatever the size.
If so, that's not an SEM issue, that's just what it looks like. Photo exposure by it's very nature doesn't edge things 100% properly, diffraction or tiny misalignments causes stuff to end up being 'soft'.
Also, keep in mind that was from 1997. Fab tech has gotten way better; although we don't have a scale reference, I imagine if you were to make the same device on modern tech everything would look a lot 'sharper'. You still can't get away from some softness though.