  Si-MOS based QD qubits are attractive due to their similarity to the current
semiconductor industry. We introduce a highly tunable MOS foundry compatible
qubit design that couples an electrostatic quantum dot (QD) with an implanted
donor. We show for the first time coherent two-axis control of a two-electron
spin qubit that evolves under the QD-donor exchange interaction and the
hyperfine interaction with the donor nucleus. The two interactions are tuned
electrically with surface gate voltages to provide control of both qubit axes.
Qubit decoherence is influenced by charge noise, which is of similar strength
as epitaxial systems like GaAs and Si/SiGe.
