The devices using individual ZnO nanowire have been manufactured by FIB. Its specific resistance and microstructural characterization has been investigated using nano manipulator and transmission electron microscopy (TEM) observations. The specific resistance was 0.2-0.4 Omega cm. With increasing the RTA temperature, the specific resistance began to be decreased and was abruptly decreased at the RTA temperature above 500 degrees C. The Pt junction of as-manufactured device consisted of the Pt nanoparticles of 5 nm and the amorphous carbon of 9.1 wt%. After RTA, the size of Pt nanoparticles grew up to 100 nm, the contents of carbon were decreased within the Pt junction, and the conductivity was enhanced due to Au diffusion into the Pt junction. It was strongly suggested that the contents of carbon is the most important factor for the electrical enhancement. (C) 2009 Elsevier B.V. All rights reserved.