We have conceived and fabricated Superconductor/Normal metal/Superconductor Josephson junctions made entirely of boron doped Silicon. We have used Gas Immersion Laser Doping to fabricate SN bilayers with good ohmic interfaces and well controlled concentration and doping depth. Standard fabrication processes, optimised for silicon, were employed to nanostructure the bilayers without affecting their transport properties. The junctions thus fabricated are proximity superconducting and show well understood I-V characteristics. This research opens the road to all-silicon, non-dissipative, Josephson Field Effect Transistors. (C) 2013 Elsevier B.V. All rights reserved.