Coulomb Blockade in a Silicon/Silicon-Germanium Two-Dimensional Electron   Gas Quantum Dot
  We report the fabrication and electrical characterization of a single electron transistor in a modulation doped silicon/silicon-germanium heterostructure. The quantum dot is fabricated by electron beam lithography and subsequent reactive ion etching. The dot potential and electron density are modified by laterally defined side gates in the plane of the dot. Low temperature measurements show Coulomb blockade with a single electron charging energy of 3.2 meV. 
L. J. Klein, K. A. Slinker, J. L. Truitt, S. Goswami, K. L. M. Lewis,   S. N. Coppersmith, D. W. van der Weide, Mark Friesen...