Kondo-like zero-bias anomaly in electronic transport through an ultrasmall si quantum dot

We have studied charge transport through an ultrasmall Si single electron transistor. We find that at low temperatures, the Coulomb blockade is partially lifted at certain gate voltages. Furthermore, we observed an enhancement of the differential conductance at zero bias. The magnetic field dependence of this zero-bias anomaly is different from that of the Kondo peaks reported in GaAs quantum dots: we observed no splitting of the zero-bias peak with magnetic field.