Something I've never been able to figure out is whether our modern, deep sub-um and even nm-scale process nodes, are directly usable for anything analog. I suspect that they aren't - that the noise levels are now at a point where even the simplest "gate"-like structures are only useful if used in combination with that "attraction/iteration towards a fix point" mechanism that essentially defines digital electronics (from an "analog" POV), with its inherent resilience to noise. Unfortunately, I even doubt that the question is directly answerable without the sorts of proprietary data that only a multi-billion chip fab would have in the first place.
They are, certain components even in the smallest process have to be analog. One good process for analog functionality is 22nm SOI, 65nm TSMC also works very well.
