If you go by handbooks, it's a mix of organic and synthetic, like a true cyborg. In practice, though, writers ditched that idea and he's basically all liquid metal machine. Closest analog would be the evil Terminator from T2.
So if you ascribe to the organic/synthetic mix - and for reference, I don't - we don't have an answer for alive or dead, because it's never really been touched on by any writer.