Both FIB deposition and its cousin Focused Electron Beam-Induced Deposition (FEBID) are pretty nifty; they can cut/add materials down to maybe 1nm (!) resolution. However, they're extremely slow: they can only affect a single spot at a time and move at maybe only 100nm/s movement, so patterning a useful circuit may take days; it's mostly useful for research work. I don't think I've seen anyone figure out the chemistry to use it to print doped semiconductors, so transistors might not be doable anyway.
Really the only other sub-micrometer 3D printing category right now is two-photon lithography (shine a laser to cure a liquid resin into a solid, like common resin 3D printing), which can generally only use a single, even-more-specialized-than-required-for-inkjet material---almost always an insulating polymer---for an entire structure.
Really the only other sub-micrometer 3D printing category right now is two-photon lithography (shine a laser to cure a liquid resin into a solid, like common resin 3D printing), which can generally only use a single, even-more-specialized-than-required-for-inkjet material---almost always an insulating polymer---for an entire structure.