Characterizing the electrical breakdown properties of single n-i-n-n+:GaN nanowires

The electrical transport properties and breakdown behaviors of single n-i-n-n+ GaN nanowires (NWs) are investigated through in-situ nanoprobing inside a scanning electron microscope (SEM). The nanoprobing contact resistance is dramatically reduced by increasing the Si-doping concentration of the top n+-GaN segment of the NW. The dependence of the NW breakdown parameters (i.e., breakdown voltage, power, and current density) on the n+-GaN Si-doping concentration and the NW diameter is experimentally quantified and explained by the localized thermal decomposition mechanism of the NW. Enabled by the low NW-nanoprobe contact resistance, a breakdown current density of 4.65 MA/cm2 and a breakdown power of 96.84 mW are achieved, both the highest among the previously reported results measured on GaN NWs.The electrical transport properties and breakdown behaviors of single n-i-n-n+ GaN nanowires (NWs) are investigated through in-situ nanoprobing inside a scanning electron microscope (SEM). The nanoprobing contact resistance is dramatically reduced by increasing the Si-doping concentration of the top n+-GaN segment of the NW. The dependence of the NW breakdown parameters (i.e., breakdown voltage, power, and current density) on the n+-GaN Si-doping concentration and the NW diameter is experimentally quantified and explained by the localized thermal decomposition mechanism of the NW. Enabled by the low NW-nanoprobe contact resistance, a breakdown current density of 4.65 MA/cm2 and a breakdown power of 96.84 mW are achieved, both the highest among the previously reported results measured on GaN NWs.