Defect-assisted tunneling current-transport mechanism for Schottky diodes of Pt thin film on p-SiNWs tips

The Schottky diodes of a Platinum (Pt) thin film on p-silicon nanowires (p-SiNWs) tips were fabricated. The current-transport mechanism of Pt/p-SiNWs Schottky diodes was defect-assisted tunneling (TU). Each silicon nanowire could be seen as a core/shell structure with a monocrystalline silicon core wrapped by a thin natural amorphous silicon oxide shell, which induced a large number of defects and enhanced the defect-assisted tunneling probability. The experimental I-V data were fitted to the theoretical mode of the thermionic emission (TE), generation-recombination (GR), TU, and leakage (RL) current-transport mechanisms in the temperature range of 300-370 K and voltage range of -1 to 1 V. The TU fitting data were in excellent agreement with the experimental data. Meanwhile, the tunneling parameter (E₀) was independent of the temperature, which closely followed the TU current-transport mechanism. Defect-assisted tunneling mechanism of Pt/p-SiNWs Schottky diodes could be applied to many other Schottky junction devices, especially, for low-dimensional nanostructures.