Focused Ion Beam Induced Nanojunction and Defect Doping as a Building Block for Nanoscale Electronics in GaN Nanowires

Two GaN nanowires are formed as a nanojunction using focused ion beam (FIB) assisted implantation of Ga+ self-ion. FIB-induced metallization and electrical isolation by cutting the nanowires are also used for the completion of contact formation. Defect doping, employing the formation energies of vacancies and interstitials, in the energetic nonequilibrium ion beam processing is successfully attempted for the formation of a p-type GaN nanowire. Detailed transport measurements of welded nanojunctions and rectification in the form of p-n junctions for two nanowires are reported in this process of in situ nanoengineering. The rectification is also reported for the p-n junction formed in a single nanowire. This is a unique technique demonstrating an all FIB nanoelectronic fabrications for future miniaturization of devices.