Modulation doping in ZnO nanorods for electrical nanodevice applications

Abstract

We introduce a modulation-doping method to control electrical characteristics of ZnO nanorods. Compared with a conventional homogeneous doping method, the modulation-doping method generates localized doping layers along the circumference in ZnO nanorods, useful for many device applications. Here, we investigated electrical, structural, and optical characteristics of Ga-doped ZnO nanorods with the dopant modulation layers. Electrical conductivity of ZnO nanorods was controlled by changing either dopant mole fraction or the number of modulation-doped layers. Furthermore, the modulation-doped nanorod field effect transistors exhibited precisely controlled conductance in the order of magnitude without degradation of electron mobility. The effects of the doping on structural and optical characteristics of the nanorods are also discussed.