Single electron and hole quantum dot transistors operating above 110 K

Both single electron and hole quantum dot transistors in silicon-on-insulator were fabricated and characterized. The quantum dots were formed using electron-beam nanolithography and reactive ion etching. The single electron quantum dot transistors show the oscillation of the drain current as a function of the gate voltage at temperatures up to 170 K and drain biases up to 80 mV. The oscillation is due to electron tunneling through the discrete energy levels inside the quantum dot. The average energy level spacing is similar to 60 meV. Data analysis shows that the discrete energy levels are caused by Coulomb interaction as well as quantum size effects. The single hole quantum dot transistors show similar oscillations up to 110 K and drain biases up to 50 mV. The average energy level spacing is similar to 36 meV. (C) 1995 American Vacuum Society.