  We integrate ambipolar quantum dots in silicon fin field-effect transistors
using exclusively standard complementary metal-oxide-semiconductor fabrication
techniques. We realize ambipolarity by replacing conventional highly-doped
source and drain electrodes by a metallic nickel silicide with Fermi level
close to the silicon mid-gap position. Such devices operate in a dual mode,
either as classical field-effect or single-electron transistor. We implement a
classical logic NOT gate at low temperature by tuning two interconnected
transistors into opposite polarities. In the quantum regime, we demonstrate
stable quantum dot operation in the few charge carrier Coulomb blockade regime
for both electrons and holes.
