An ion-implanted silicon single-electron transistor
  We report on the fabrication and electrical characterization at millikelvin temperatures of a novel silicon single-electron transistor (Si-SET). The island and source-drain leads of the Si-SET are formed by the implantation of phosphorus ions to a density above the metal-insulator-transition, with the tunnel junctions created by undoped regions. Surface gates above each of the tunnel junctions independently control the tunnel coupling between the Si-SET island and leads. The device shows periodic Coulomb blockade with a charging energy e$^2$/2C$_\Sigma$ $\sim$ 250 $\mu$eV, and demonstrates a reproducible and controllable pathway to a silicon-based SET using CMOS processing techniques. 
V.C. Chan, D.R. McCamey, T.M. Buehler, A.J. Ferguson, D.J. Reilly,   A.S. Dzurak, R.G. Clark, C. Yang, D.N. Jamieson