Effects of Parasitic MOSFETs and Traps on Charge Transport Properties of Germanium Quantum Dot Single Electron/Hole Transistors

Ge quantum-dot (QD) single electron and single hole transistors (SETs/SHTs) have be experimentally fabricated with Ge QDs formed by selective oxidation of Si0.95Ge0.05/Si-on-insulator nanowires. The turn-on voltages of Ge QD SETs/SHTs could be modulated by adjusting the top Si layer thickness or applying back gate biases due to parasitic MOSFETs effect. In addition to quantum confinement and coulomb charging effects, drain current hysteresis memory effects have also been observed both in SETs and SHTs at room temperature. The charge storage in the Ge QD SET and SHT might be attributed to the traps at the internal/surface of Ge QDs and the interface states between SiO2and Si.