Electronic passivation of single-crystal, atomically flat (001) surfaces of cubic silicon carbide (3C-SiC) was attempted via hydrogen annealing and HF exposure and investigated by monitoring the surface potentials of the treated samples. It was found that HF treatment causes a negative charging of the surface and that only hydrogen annealing is effective in producing well-passivated 3C-SiC. The degree and stability of the surface electronic passivation was dependent on the final hydrogen cooling temperature of the annealing process. Surface charge densities of the hydrogen-treated surfaces were calculated from the measured surface potentials and were found to be in the 10(10) cm(-2) range.