Interface modification and trap-type transformation in Al-doped CdO/Si-nanowire arrays/p-type Si devices by nanowire surface passivation

• AlCdO/H2O2-treated Si nanowires/p-type Si devices show a good rectifying behavior.
• The charge trap density in Si nanowires (SiNWs) is changed by H2O2 treatment.
• The dominance transformation from electron traps to hole traps is found.
• SiNW surface passivation plays a significant role in the carrier conduction.

The present work reports the fabrication and detailed electrical properties of Al-doped CdO/Si-nanowire (SiNW) arrays/p-type Si Schottky diodes with and without SiNW surface passivation. It is shown that the interfacial trap states influence the electronic conduction through the device. The experimental results demonstrate that the effects of the dangling bonds at the SiNW surface and Si vacancies at the SiOx/SiNW interface which can be changed by the Si–O bonding on the energy barrier lowering and the charge transport property. The induced dominance transformation from electron traps to hole traps in the SiNWs by controlling the passivation treatment time is found in this study.