Growth and electronic properties of GaN/ZnO solid solution nanowires

We have grown single-crystal (Ga_1-xZn_x)(N_1-xO_x) solid-solution nanowires using nanostructured ZnGa₂O₄ precursor prepared by a sol-gel method. From electrical transport measurements in individual nanowire field-effect transistors, we have identified the conduction as n-type and obtained a background carrier density (∼10¹⁹ cm^-3) and an electron mobility (∼1 cm²/V s) that are consistent with chemical disorder and a large number of charge traps, as confirmed by the devices’ photocurrent response. From the dependence of the device photoresponse on incident light wavelength, we have determined the energy band gap of (Ga_0.88Zn_0.12)(N_0.88O_0.12) to be as much as ∼0.6 eV lower than that of GaN or ZnO.