Si doping-induced phase control, formation of p-type and n-type GaAs nanowires

We realized the control on the crystal structure of GaAs nanowires (NWs) by silicon (Si) doping and V/III ratio. This viewpoint has been clearly evidenced by Raman spectrum combined with high-resolution transmission electron microscopy (HRTEM). Undoped GaAs NWs generally show a mixture of zinc blende (ZB) and wurtzite (WZ) phases; the addition of Si dopant and high V/III ratio are beneficial for the nucleation of ZB structure. Field effect transistor (FET) devices were fabricated to show that Si-doped GaAs NWs exhibit p-type conductivity in the low V/III ratio of 25.8 and n-type conductivity in the high V/III ratio of 51.6. These results provide a clear route for achieving GaAs NWs phase control and different conductivity types, which is an essential step towards the fabrication of nanoscale devices.

Automated summary

Controlling the crystal structure of GaAs nanowires with Si doping and V/III ratio has been shown to influence the nucleation of ZB phase and result in different conductivity types in FET devices. These results provide a clear route towards nanoscale device fabrication.